CN111272739A - Method for measuring percentage content of bismuth and indium in tin-indium-bismuth composite oxide powder by ICP-AES method - Google Patents
Method for measuring percentage content of bismuth and indium in tin-indium-bismuth composite oxide powder by ICP-AES method Download PDFInfo
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- 229910052738 indium Inorganic materials 0.000 title claims abstract description 134
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 title claims abstract description 133
- 229910052797 bismuth Inorganic materials 0.000 title claims abstract description 132
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 title claims abstract description 131
- 239000000843 powder Substances 0.000 title claims abstract description 90
- 239000002131 composite material Substances 0.000 title claims abstract description 89
- PSMFTUMUGZHOOU-UHFFFAOYSA-N [In].[Sn].[Bi] Chemical compound [In].[Sn].[Bi] PSMFTUMUGZHOOU-UHFFFAOYSA-N 0.000 title claims abstract description 75
- 238000000034 method Methods 0.000 title claims abstract description 59
- 238000002354 inductively-coupled plasma atomic emission spectroscopy Methods 0.000 title claims abstract description 20
- 239000012086 standard solution Substances 0.000 claims abstract description 100
- 239000000243 solution Substances 0.000 claims abstract description 54
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000009616 inductively coupled plasma Methods 0.000 claims abstract description 21
- 239000007788 liquid Substances 0.000 claims abstract description 15
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 63
- 230000003595 spectral effect Effects 0.000 claims description 53
- 238000004458 analytical method Methods 0.000 claims description 39
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 22
- 238000005259 measurement Methods 0.000 claims description 15
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 14
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 14
- 239000012490 blank solution Substances 0.000 claims description 13
- 238000012360 testing method Methods 0.000 claims description 12
- 238000001514 detection method Methods 0.000 claims description 10
- 238000002156 mixing Methods 0.000 claims description 9
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 7
- 238000009835 boiling Methods 0.000 claims description 7
- 238000001816 cooling Methods 0.000 claims description 7
- 238000002386 leaching Methods 0.000 claims description 7
- 239000000155 melt Substances 0.000 claims description 7
- PFUVRDFDKPNGAV-UHFFFAOYSA-N sodium peroxide Chemical compound [Na+].[Na+].[O-][O-] PFUVRDFDKPNGAV-UHFFFAOYSA-N 0.000 claims description 7
- 238000005303 weighing Methods 0.000 claims description 7
- 238000002360 preparation method Methods 0.000 claims description 5
- 238000004364 calculation method Methods 0.000 claims description 4
- 230000035945 sensitivity Effects 0.000 claims description 4
- 238000001228 spectrum Methods 0.000 claims description 4
- 229910052759 nickel Inorganic materials 0.000 claims description 3
- 230000006641 stabilisation Effects 0.000 claims description 3
- 238000011105 stabilization Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 239000000523 sample Substances 0.000 description 5
- 239000000956 alloy Substances 0.000 description 3
- 238000000295 emission spectrum Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- RHZWSUVWRRXEJF-UHFFFAOYSA-N indium tin Chemical compound [In].[Sn] RHZWSUVWRRXEJF-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 229910001887 tin oxide Inorganic materials 0.000 description 2
- 238000004448 titration Methods 0.000 description 2
- 229910001152 Bi alloy Inorganic materials 0.000 description 1
- 229910018978 Sn—In—Bi Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000012488 sample solution Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/71—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited
- G01N21/73—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited using plasma burners or torches
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Abstract
The invention discloses a method for measuring the percentage content of bismuth and indium in tin-indium-bismuth composite oxide powder by an ICP-AES method, which comprises the steps of adding 1000 mu g/mL indium standard solutions and bismuth standard solutions with different volumes into a 250mL volumetric flask containing a tin-based solution, respectively preparing a series of working standard solutions containing indium and bismuth with different contents, respectively measuring the series of working standard solutions under the determined working parameters of an inductively coupled plasma atomic emission spectrometer, establishing working curves of the emission line strength and the concentration value of the series of working standard solutions, measuring a liquid to be measured of the tin-indium-bismuth composite oxide powder, and automatically calculating the percentage content of indium and bismuth in the tin-indium-bismuth composite oxide powder by the inductively coupled plasma atomic emission spectrometer. The method can simultaneously calculate the percentage contents of bismuth and indium, and provides basis and data support for controlling the quality and performance of the tin-indium-bismuth composite oxide powder.
Description
Technical Field
The invention relates to the technical field of analysis and test, in particular to a method for measuring the percentage content of bismuth and indium in tin-indium-bismuth composite oxide powder by an ICP-AES method, which is a short name for an inductively coupled plasma atomic emission spectrometry.
Background
With the development of environment-friendly electrical alloy materials, the domestic electrical alloy industry has a strong demand for high-performance tin oxide powder. The tin oxide composite powder doped with indium, bismuth, antimony and the like has obvious advantages in improving the comprehensive performance of the contact alloy, and can better meet the market demand of small-sized high-power electric contact devices. The composite oxide powder has different types and dosages of elements, and the obtained materials have different properties. The metal elements in the composite oxide powder need to be accurately determined and controlled.
The method for measuring indium in tin-indium-bismuth composite oxide powder by EDTA complex titration method, which is published in Material research and application No. 4, 2010, on No. 3, has the problems of incomplete dissolution of ① sample, incapability of measuring low-content indium, ③, which is used for removing interference of tin and bismuth, of separating indium from tin and bismuth by extraction and other methods, measuring indium by EDTA complex titration method, the method has the problems of multiple steps, long period, large workload, multiple required reagent types, large required reagent types and the like, and the method for measuring indium by using the method without bismuth only has the advantages of long period, large working amount, simultaneous measurement of indium in tin-indium composite oxide powder, bismuth composite oxide powder, and accurate control of the quality of tin-indium composite oxide powder and bismuth alloy produced by the modern method.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides the method for measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by the ICP-AES method, the percentage content of bismuth and indium can be simultaneously calculated by the measuring method, and a basis and data support are provided for controlling the quality and the performance of the tin-indium-bismuth composite oxide powder. The analysis ranges of bismuth and indium in the tin-indium-bismuth composite oxide powder are respectively as follows: 0.25-25.00% and 0.25-30.00%.
In order to achieve the purpose, the invention adopts the specific scheme that:
the method for measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by the ICP-AES method comprises the following steps:
(1) preparing a tin-based solution, an indium standard solution and a bismuth standard solution, and then preparing a series of working standard solutions with bismuth element concentration ranging from 0 to 100 mu g/mL and indium element concentration ranging from 0 to 120 mu g/mL by using the tin-based solution, the indium standard solution and the bismuth standard solution;
(2) accurately weighing 0.0900-0.1500 g of tin indium bismuth composite oxide powder, placing the tin indium bismuth composite oxide powder into a crucible containing 0.4-0.8 g of sodium hydroxide, respectively adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucible, mixing, covering the crucible with 0.4-0.8 g of sodium hydroxide, placing the crucible into a muffle furnace heated to 700-720 ℃, keeping the temperature for a period of time, taking out, leaching the melt in the crucible with hot pure water into a beaker, slowly adding 25mL of hydrochloric acid into the beaker, boiling on an electric furnace until the solution is clear, taking down and cooling to room temperature, transferring into a 250mL volumetric flask, and fixing the volume to the scale with water to obtain a to-be-measured solution of the tin indium bismuth composite oxide powder;
(3) scanning and measuring the series of working standard solutions in the step (1) and the to-be-measured solution of the tin-indium-bismuth composite oxide powder in the step (2) by using an inductively coupled plasma atomic emission spectrometer, and selecting analysis spectral lines of bismuth and indium by combining the conditions of a spectrum, the interference degree, whether an interference peak can be distinguished, the signal-to-back ratio condition and the test comparison condition of the series of working standard solutions containing bismuth and indium;
(4) establishing a corresponding working curve and obtaining a method linear equation according to the intensity values of the bismuth and indium analysis spectral lines selected in the step (3) and the concentration values of the bismuth and indium analysis spectral lines, then measuring the liquid to be measured of the tin-indium-bismuth composite oxide powder and obtaining the bismuth and indium element emission spectral line intensity, and automatically calculating the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by an inductively coupled plasma atomic emission spectrometer according to the working curve.
Further, the series of working standard solutions comprise a blank solution and at least three standard solutions, wherein the blank solution does not contain bismuth and indium, and the standard solutions contain bismuth and indium.
Further, the preparation method of the series working standard solution comprises the following steps:
(a) preparing a tin-based solution: weighing 0.0500-0.1000 g of spectrally pure tin dioxide, placing the spectrally pure tin dioxide in a nickel crucible containing 0.4-0.8 g of sodium hydroxide, adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucibles respectively, mixing, covering the crucibles with 0.4-0.8 g of sodium hydroxide, placing the crucibles in a muffle furnace which is heated to 700-720 ℃ for a certain time, taking out the crucibles, leaching the melts in the crucibles in a 250mL beaker with hot pure water, slowly adding 25mL of hydrochloric acid into the beaker, boiling on an electric furnace until the solution is clear, taking down, cooling to room temperature, and transferring into a 250mL volumetric flask to obtain a tin-based solution; repeating the steps to prepare 7 parts of tin-based solution, and respectively placing 7 parts of tin-based solution into 7 volumetric flasks;
(b) preparing a blank solution: adding water to 1 of the volumetric flasks until the 250mL mark of the volumetric flask is reached to form a blank solution;
(c) preparing standard solutions with different concentrations: adding 1000ug/mL of indium standard solution into the other 6 volumetric flasks according to the amount of 1mL, 5mL, 10mL, 30mL, 0.25mL and 20mL, adding 1000ug/mL of bismuth standard solution into the volumetric flasks according to the amount of 1mL, 3mL, 5mL, 10mL, 25mL and 0.25mL, adding water to the 250mL scale lines of the volumetric flasks, and mixing all the substances in the volumetric flasks uniformly to obtain six standard solutions including a standard A, a standard B, a standard C, a standard D, a standard E and a standard F;
wherein, the concentration of the indium element in the standard solution A is 4ug/mL, and the concentration of the bismuth element is 4 ug/mL;
the concentration of indium element in the standard solution B is 20ug/mL, and the concentration of bismuth element is 12 ug/mL;
the concentration of indium element in the standard solution C is 40ug/mL, and the concentration of bismuth element is 20 ug/mL;
the concentration of indium element in the standard solution D is 120ug/mL, and the concentration of bismuth element is 40 ug/mL;
the concentration of indium element in the standard solution E is 1ug/mL, and the concentration of bismuth element is 100 ug/mL;
the concentration of indium element in standard solution F is 80ug/mL, and the concentration of bismuth element is 1 ug/mL.
Further, in the step (3), the operating parameters of the inductively coupled plasma atomic emission spectrometer are as follows:
power: 1.0 KW-1.3 KW;
plasma gas flow rate: 12L/min to 13L/min;
auxiliary air flow rate: 1.0L/min-1.1L/min;
flow rate of atomizing gas: 0.70L/min-0.85L/min;
pump speed: 12rpm to 13 rpm;
stabilization delay time: 10 s-12 s;
sample lifting time: 10 s-13 s;
reading time: 5s-6 s;
the number of repeated measurements: 2 times to 3 times;
observation height: 14 mm.
Further, the analytical spectral lines selected in the step (3) are spectral lines with high sensitivity and little interference of the matrix elements to the selected spectral lines, and the analytical spectral lines of the selected bismuth and indium are as follows: bi 223.061nm and In 410.176 nm.
Further, in the step (4), besides the establishment of the linear equation of the method, the calculation of the correlation coefficient, the detection limit, the lower determination limit and the relative standard deviation is also included, wherein the correlation coefficient is more than or equal to 0.999, the detection limit is less than or equal to 0.010 percent, and the relative standard deviation is less than or equal to 1 percent.
Has the advantages that:
1. in the determination method, after the working parameters and the analysis spectral line of the inductively coupled plasma atomic emission spectrometer are determined, the linear equation of the method can be determined by determining the series of working standard solutions, and then the percentage content of bismuth and indium in the tin indium bismuth composite oxide powder can be determined and calculated by analyzing the liquid to be determined of the tin indium bismuth composite oxide powder, so that the analysis time is saved, and the requirements of scientific research and production can be met.
2. The determination method can simultaneously analyze and determine the percentage contents of bismuth and indium in the tin indium bismuth composite oxide powder on the inductively coupled plasma atomic emission spectrometer, has simple operation, accurate result and quick analysis, solves the problems of multiple steps and long period of the existing method and incapability of simultaneously determining the percentage contents of bismuth and indium in the tin indium bismuth composite oxide powder, and provides a quick and accurate reference basis for the production control and the application of the tin indium bismuth composite oxide powder.
3. The correlation coefficient of the method is more than or equal to 0.999, the detection limit is less than or equal to 0.010 percent, and the relative standard deviation is less than or equal to 1 percent, which shows that the method can meet the requirement of measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, belong to the scope of the present invention.
The inductively coupled plasma atomic emission spectrometry has the characteristics of simplicity, rapidness and accuracy, and aims to solve the problem that the inductively coupled plasma atomic emission spectrometry is not available for simultaneously measuring the percentage content of bismuth and indium in tin-indium-bismuth composite oxide powder, the invention provides a method for measuring the percentage content of bismuth and indium in tin-indium-bismuth composite oxide powder by inductively coupled plasma atomic emission spectrometry (ICP-AES method), a series of working standard solutions of the method are prepared by respectively adding bismuth and indium standard solutions into a tin standard solution, the series of working standard solutions are respectively tested under the premise of determining the working conditions of the inductively coupled plasma atomic emission spectrometry, a working curve is drawn by taking the bismuth and indium concentrations as horizontal coordinates and the emission line intensity as vertical coordinates, and the bismuth and indium emission spectrum intensities in a liquid to be measured of the tin-indium-bismuth composite oxide powder are measured, and calculating the percentage contents of bismuth and indium in the tin indium bismuth composite oxide powder, and providing basis and data support for controlling the quality and performance of the tin indium bismuth composite oxide powder.
The equipment used in the following examples is conventional in the art, and the experimental procedures in the following examples, in which specific conditions are not specified, generally follow conventional conditions, or follow conditions recommended by the manufacturer, and the various starting materials used in the following examples, unless otherwise specified, are conventional commercially available products. The indium standard solution and the bismuth standard solution are all commercial products.
The method for measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by the ICP-AES method comprises the following steps:
(1) respectively preparing a tin-based solution, an indium standard solution and a bismuth standard solution, and then preparing a series of working standard solutions with bismuth element concentration ranging from 0 to 100 mu g/mL and indium element concentration ranging from 0 to 120 mu g/mL by using the tin-based solution, the indium standard solution and the bismuth standard solution; including a blank solution and at least three standard solutions.
(2) Weighing 0.0900-0.1500 g of tin indium bismuth composite oxide powder, placing the tin indium bismuth composite oxide powder into a crucible containing 0.4-0.8 g of sodium hydroxide, adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucible respectively, mixing, covering the crucible with 0.4-0.8 g of sodium hydroxide, placing the crucible into a muffle furnace heated to 700-720 ℃, keeping the temperature for a period of time, taking out, leaching the melt in the crucible with hot pure water into a beaker, slowly adding 25mL of hydrochloric acid into the beaker, placing the beaker on an electric furnace until the solution is clear, taking out and cooling to room temperature, transferring into a 250mL volumetric flask, and boiling with water to a constant volume to obtain a to-be-measured solution of the tin indium bismuth composite oxide powder;
(3) scanning and measuring the series of working standard solutions obtained in the step (1) and the to-be-measured solution of the tin-indium-bismuth composite oxide powder obtained in the step (2) by using an inductively coupled plasma atomic emission instrument, and selecting analysis spectral lines of bismuth and indium by combining the conditions of a spectrum, the interference degree, whether an interference peak can be distinguished, the signal-to-back ratio condition and the test comparison condition of the series of working standard solutions containing bismuth and indium;
(4) establishing a corresponding working curve and obtaining a method linear equation according to the bismuth and indium analysis spectral line intensity values and the concentration values of the bismuth and indium analysis spectral line intensity values selected in the step (3), then measuring the liquid to be measured of the tin-indium-bismuth composite oxide powder and obtaining the bismuth and indium element emission spectral line intensity, and automatically calculating the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by an inductively coupled plasma atomic emission spectrometer according to the working curve.
DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
The method for measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by the ICP-AES method comprises the following specific steps:
(1) the preparation method of the tin-based solution comprises the following steps: weighing 0.0500-0.1000 g of spectrally pure tin dioxide, placing the spectrally pure tin dioxide in a nickel crucible filled with 0.4-0.8 g of sodium hydroxide, adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucible, mixing, and covering the crucible with 0.4-0.8 g of sodium hydroxide. Placing the crucible in a muffle furnace heated to 720 ℃ for heat preservation for 20min, taking out, leaching the melt in the crucible with hot pure water in a 250mL beaker, slowly adding 25mL hydrochloric acid into the beaker, boiling on an electric furnace until the solution is clear, taking down, and cooling to room temperature to obtain a tin-based solution;
(2) preparing a series of working standard solutions by using a bismuth standard solution, an indium standard solution and the tin-based solution prepared in the step (1); the preparation steps of the series of working standard solutions are as follows:
(a) preparing 7 parts of tin-based solution according to the method in the step (1), and respectively placing 7 parts of tin-based solution into 7 volumetric flasks;
(b) adding water into the 1 st volumetric flask until the position of a 250mL scale mark of the volumetric flask to form a blank solution;
(c) accurately adding 1mL of 1000 mu g/mL indium and 1mL of 1000 mu g/mL bismuth standard solution into the 2 nd volumetric flask containing 1 part of tin-based solution, adding water till the 250mL scale mark of the volumetric flask, and shaking uniformly to obtain a standard solution A, wherein the concentrations of the indium and the bismuth in the solution are both 4 mu g/mL;
(d) accurately adding 5mL of 1000 mu g/mL indium and 3mL of 1000 mu g/mL bismuth standard solution into the 3 rd volumetric flask containing 1 part of tin-based solution, adding water till the position of 250mL scale lines of the volumetric flask, and shaking uniformly to obtain a standard B standard solution, wherein the concentrations of the indium and the bismuth in the solution are respectively 20 mu g/mL and 12 mu g/mL;
(e) accurately adding 10mL of 1000 mu g/mL indium and 5mL of 1000 mu g/mL bismuth standard solution into a 4 th volumetric flask containing 1 part of tin-based solution, adding water till the position of a 250mL scale mark of the volumetric flask, and shaking uniformly to obtain a standard C standard solution, wherein the concentrations of the indium and the bismuth in the solution are 40 mu g/mL and 20 mu g/mL respectively;
(f) accurately adding 30mL of 1000 mu g/mL indium and 10mL of 1000 mu g/mL bismuth standard solution into the 5 th volumetric flask containing 1 part of tin-based solution, adding water till the 250mL scale mark of the volumetric flask, and shaking uniformly to obtain a standard D standard solution, wherein the concentrations of the indium and the bismuth in the standard D standard solution are 120 mu g/mL and 40 mu g/mL respectively;
(g) accurately adding 0.25mL of 1000 mu g/mL indium and 25mL of 1000 mu g/mL bismuth standard solution into the 6 th volumetric flask containing 1 part of tin-based solution, adding water till the position of 250mL of a scale mark of the volumetric flask, and shaking uniformly to obtain a standard E standard solution, wherein the concentrations of indium and bismuth in the standard E standard solution are 1 mu g/mL and 100 mu g/mL respectively;
(h) and accurately adding 20mL of 1000 mu g/mL indium and 0.25mL of 1000 mu g/mL bismuth standard solution into the 7 th volumetric flask containing 1 part of tin-based solution, adding water till the position of a 250mL scale mark of the volumetric flask, and shaking uniformly to obtain a standard F standard solution, wherein the concentrations of the indium and the bismuth in the standard F standard solution are respectively 80 mu g/mL and 1 mu g/mL.
(3) And weighing 0.0900-0.1500 g of the tin indium bismuth composite oxide powder, placing the tin indium bismuth composite oxide powder in a crucible filled with 0.4-0.8 g of sodium hydroxide, respectively adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucible, mixing, and covering the crucible with 0.4-0.8 g of sodium hydroxide. Placing the crucible in a muffle furnace heated to 700-720 ℃ for heat preservation for a period of time, taking out, leaching the melt in the crucible with hot pure water in a 250mL beaker, slowly adding 25mL hydrochloric acid into the beaker, boiling on an electric furnace until the solution is clear, taking down and cooling to room temperature, transferring into a 250mL volumetric flask, diluting with water and fixing the volume to a scale mark to obtain a to-be-detected liquid of the tin-indium-bismuth composite oxide powder;
(4) scanning and measuring the series of working standard solutions in the step (2) and the to-be-measured solution of the tin-indium-bismuth composite oxide powder in the step (3) by using an inductively coupled plasma atomic emission spectrometer, and selecting analysis spectral lines of bismuth and indium by combining the conditions of a spectrum, the interference degree, whether an interference peak can be distinguished, the signal-to-back ratio condition and the test comparison condition of the series of working standard solutions containing bismuth and indium;
the work parameters of the inductively coupled plasma atomic emission spectrometer are as follows: power: 1.0 KW-1.3 KW; plasma gas flow rate: 12L/min to 13L/min; auxiliary air flow rate: 1.0L/min-1.1L/min; flow rate of atomizing gas: 0.70L/min-0.85L/min; pump speed: 12rpm to 13 rpm; stabilization delay time: 10 s-12 s; sample lifting time: 10 s-13 s; reading time: 5s-6 s; the number of repeated measurements: 2 times to 3 times; observation height: 14 mm.
Preselecting a plurality of spectral lines of Bi and In elements from an element spectral line chart, and respectively scanning blank solution, standard A standard solution, standard B standard solution, standard C standard solution, standard D standard solution, standard E standard solution, standard F standard solution and to-be-detected liquid of the Sn-In-Bi composite oxide powder, wherein the interference conditions of the spectral lines are as follows:
no interference is seen in the Bi 179.124nm analysis spectral line;
interference spectral lines are not seen in the Bi 190.171nm spectral line, but the spectral peak is very wide;
interference of Al 237.335nm exists in a Bi 206.163nm analysis spectral line;
no interference spectral line is seen in the Bi 222.821nm analysis spectral line;
no interference spectral line is seen in the Bi 223.061nm analysis spectral line;
interference of Ni 227.644nm exists on the left side of an analysis spectral line of Bi 227.654 nm;
no interference spectral line is found in the Bi289.799 nm analysis spectral line;
the peak of the Bi 306.771nm analysis spectral line is very wide, and the interference of OH306.793nm exists on the right side;
interference of Fe 230.606nm exists at the right side of an In 230.606nm analysis spectral line;
the left side of the In 303.936nm analysis spectral line has slope interference;
interference of Fe 325.589nm exists In an In 325.609nm analysis spectral line;
interference of Fe 325.877nm exists In an In 325.856nm analysis spectral line;
no interference spectral line is seen In the In 410.176nm analysis spectral line;
in the test, Bi 306.771nm has high intensity and high sensitivity, but has wide peak, and an interference peak OH306.793nm is arranged on the right side; the sensitivity of Bi 179.124nm and Bi 206.163nm is low, and the relative standard deviation RSD value is poor. And finally selecting the following components by combining the spectrogram condition, the interference degree, whether the interference peak can be distinguished, the signal-to-back ratio condition and the test comparison condition of each working standard solution containing bismuth and indium:
bi 223.061nm and In 410.176nm are analysis spectral lines of bismuth and indium In the tin-indium-bismuth composite oxide powder.
The analysis of bismuth and indium in the tin-indium-bismuth composite oxide powder has less chemical interference, and mainly has physical interference and spectral interference, the physical interference on the analysis and determination of bismuth and indium is eliminated by adopting a matrix matching method, and the spectral interference on the analysis and determination of bismuth and indium is eliminated by selecting a proper analysis line.
(5) Establishing a corresponding working curve and obtaining a method linear equation according to the bismuth and indium analysis spectral line intensity values and the concentration values of the bismuth and indium analysis spectral line intensity values selected in the step (4), then measuring a liquid to be measured of the tin-indium-bismuth composite oxide powder and obtaining the bismuth and indium element emission spectral line intensity of the liquid, and automatically calculating the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by an inductively coupled plasma atomic emission spectrometer according to the working curve;
besides the establishment of a method linear equation, the method also comprises the calculation of a correlation coefficient, a detection limit, a measurement lower limit and a relative standard deviation, and in detail, the calculation method of each parameter is as follows:
detection limit: continuously measuring the blank of the working standard solution for 10 times, and multiplying the standard deviation average value of 10 times of measurement by 3 to obtain a detection limit;
lower limit of measurement: multiplying the standard deviation average of 10 times of measurement by 10 to obtain the lower measurement limit;
relative Standard Deviation (RSD): repeatedly measuring the to-be-measured liquid of the tin indium bismuth composite oxide powder for 10 times to obtain the relative standard deviation of the method;
the linear equation, the correlation coefficient, the detection limit and the reference value of the relative standard deviation corresponding to each selected analysis spectral line are summarized as follows:
| elemental wavelength/nm | Linear equation of equations | Correlation coefficient | Detection limit/%) | Determination lower limit/%) | RSD/％ |
| Bi223.061 | y＝638.16x+1.90 | 0.99998 | 0.0044 | 0.015 | 0.51 |
| In410.176 | y＝2356.11x+100.24 | 0.99999 | 0.00021 | 0.0007 | 0.70 |
The process provides basic conditions and basic working parameters for measuring the contents of bismuth and indium in the tin indium bismuth composite oxide powder, once the method for measuring the contents of bismuth and indium in the tin indium bismuth composite oxide powder is established in an inductively coupled plasma atomic emission spectrometer, the method for measuring the contents of bismuth and indium in the tin indium bismuth composite oxide powder can be selected and used only after the instrument is started and stabilized for 10 minutes during the test, and the working curves can be established by performing spectral intensity measurement on at least four working standard solutions in a blank solution, a standard A solution, a standard B solution, a standard C solution, a standard D solution, a standard E solution and a standard F solution according to the content of bismuth and indium in a sample by only naming the names of the files stored for testing, wherein the spectral intensity measurement of the blank solution is required to be included, and then the spectral intensity measurement is performed on the liquid to be measured in the tin indium bismuth composite oxide powder, the percentage content of bismuth and indium in the tin indium bismuth composite oxide powder is calculated by an inductively coupled plasma atomic emission spectrometer according to a linear equation of a working curve, parameters and conditions do not need to be selected, the determination time is saved, the whole on-board analysis and test time can be completed within 1 hour, if all the time such as the preparation of a series of working standard solutions in the previous period is added, the analysis and determination of the percentage content of bismuth and indium in one tin indium bismuth composite oxide powder sample can be completed within 8 hours, and the requirements of scientific research and production can be met.
It is to be emphasized that:
1. the method is not only suitable for measuring and analyzing bismuth and indium in the tin indium bismuth composite oxide powder with common particle size, but also suitable for insoluble nano tin indium bismuth composite oxide powder.
2. For the tin indium bismuth composite oxide powder with the same quality, no matter what the value is weighed in the range of 0.0900 g-0.1500 g, the percentage content of bismuth and indium calculated by an inductively coupled plasma atomic emission spectrometer is unique, for example, 0.0900g or 0.1500g of the tin indium bismuth composite oxide powder with the same quality is simultaneously weighed to respectively prepare two liquids to be tested of the tin indium bismuth composite oxide powder, and the reference values of the percentage content of bismuth and indium in the liquids to be tested of the two tin indium bismuth composite oxide powders are 4.07% of bismuth and 5.42% of indium.
3. For different qualities of sn-in-bi composite oxide powder, even if the values weighed in the range of 0.0900g to 0.1500g are equal, the percentages of bismuth and indium calculated by an inductively coupled plasma atomic emission spectrometer are unequal, for example, 0.1100g of a quality a sn-in-bi composite oxide powder or 0.1100g of a quality b-in-bi composite oxide powder is weighed, and a solution to be tested of the quality a-in-bi composite oxide powder or a solution to be tested of the quality b-in-bi composite oxide powder is prepared, then the percentages of bismuth and indium in the quality a-in-bi composite oxide powder are as follows: 2.35 percent of bismuth and 4.14 percent of indium, and the percentage content reference values of bismuth and indium in the B-quality tin-indium-bismuth composite oxide powder are as follows: 1.2 percent of bismuth and 4.27 percent of indium.
However, the relative standard deviation obtained by repeating the measurement 10 times on the Sn-in-Bi composite oxide powder sample solution was 1% or less.
From this, the correlation coefficient of the present invention: bismuth: 0.9998, indium: 0.99999, which is not less than 0.999, and meets the requirement that the correlation coefficient of the general method is not less than 0.995; lower limit of measurement of the present invention: bismuth: 0.015 percent and 0.0007 percent of indium meet the requirement of measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder.
Recovery test
Adding a bismuth standard solution and an indium standard solution into a to-be-detected solution of the tin-indium-bismuth composite oxide powder with the detected bismuth and indium contents, and calculating the recovery rates of bismuth and indium to be 95-109% through a recovery test, thereby proving that the determination method is completely feasible.
As is evident from the above analysis: the method comprises the steps of adding 1000 mu g/mL indium standard solution and bismuth standard solution with different volumes into a 250mL volumetric flask containing tin-based solution, respectively preparing a series of working standard solutions containing indium and bismuth with different contents, respectively measuring the series of working standard solutions under the determined working parameters of an inductively coupled plasma atomic emission spectrometer, establishing a working curve between the intensity value of an emission spectrum line of the series of working standard solutions and the concentration value of the emission spectrum line, measuring the liquid to be measured of the prepared tin-indium-bismuth composite oxide powder, and automatically calculating the percentage contents of indium and bismuth in the tin-indium-bismuth composite oxide powder by the inductively coupled plasma atomic emission spectrometer.
The foregoing is merely a preferred embodiment of the invention and is not to be construed as limiting the invention in any way. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Claims (6)
- The method for measuring the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by the ICP-AES method is characterized by comprising the following steps of:(1) respectively preparing a tin-based solution, an indium standard solution and a bismuth standard solution, and then preparing a series of working standard solutions with bismuth element concentration ranging from 0 to 100 mu g/mL and indium element concentration ranging from 0 to 120 mu g/mL by using the tin-based solution, the indium standard solution and the bismuth standard solution;(2) accurately weighing 0.0900-0.1500 g of tin indium bismuth composite oxide powder, placing the tin indium bismuth composite oxide powder into a crucible containing 0.4-0.8 g of sodium hydroxide, respectively adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucible, mixing, covering the crucible with 0.4-0.8 g of sodium hydroxide, placing the crucible into a muffle furnace heated to 700-720 ℃, keeping the temperature for a period of time, taking out, leaching the melt in the crucible with hot pure water into a beaker, slowly adding 25mL of hydrochloric acid into the beaker, boiling on an electric furnace until the solution is clear, taking down and cooling to room temperature, transferring into a 250mL volumetric flask, and fixing the volume to the scale with water to obtain a to-be-measured solution of the tin indium bismuth composite oxide powder;(3) scanning and measuring the series of working standard solutions obtained in the step (1) and the to-be-measured solution of the tin-indium-bismuth composite oxide powder obtained in the step (2) by using an inductively coupled plasma atomic emission spectrometer, and selecting analysis spectral lines of bismuth and indium by combining the conditions of a spectrum, the interference degree, whether an interference peak can be distinguished, the signal-to-back ratio and the test comparison condition of the series of working standard solutions containing bismuth and indium;(4) establishing a corresponding working curve and obtaining a method linear equation according to the intensity values of the bismuth and indium analysis spectral lines selected in the step (3) and the concentration values of the bismuth and indium analysis spectral lines, then measuring the liquid to be measured of the tin-indium-bismuth composite oxide powder and obtaining the intensity of bismuth and indium element emission spectral lines, and automatically calculating the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder by an inductively coupled plasma atomic emission spectrometer according to the working curve.
- 2. The ICP-AES method for determining percentage contents of bismuth and indium in tin-indium-bismuth composite oxide powder according to claim 1, wherein the series of working standard solutions comprises a blank solution and at least three standard solutions, wherein the blank solution does not contain bismuth and indium, and the standard solutions contain bismuth and indium.
- 3. The ICP-AES method for determining the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder according to claim 2, wherein the preparation method of the series of working standard solutions comprises the following steps:(a) preparing a tin-based solution: weighing 0.0500-0.1000 g of spectrally pure tin dioxide, placing the spectrally pure tin dioxide in a nickel crucible filled with 0.4-0.8 g of sodium hydroxide, adding 1g of sodium hydroxide and 0.8-1.2 g of sodium peroxide into the crucibles respectively, mixing, covering the crucibles with 0.4-0.8 g of sodium hydroxide, placing the crucibles in a muffle furnace heated to 700-720 ℃ for a period of time, taking out the crucibles, leaching the melts in the crucibles in 250mL beakers with hot pure water, slowly adding 25mL of hydrochloric acid into the beakers, boiling on an electric furnace until the solution is clear, taking down, and cooling to room temperature to obtain a tin-based solution; repeating the steps to prepare 7 parts of tin-based solution, and respectively placing 7 parts of tin-based solution into 7 volumetric flasks;(b) preparing a blank solution: adding water to 1 of the volumetric flasks until the 250mL mark of the volumetric flask is reached to form a blank solution;(c) preparing standard solutions with different concentrations: adding 1000ug/mL of indium standard solution into the other 6 volumetric flasks according to the amount of 1mL, 5mL, 10mL, 30mL, 0.25mL and 20mL, adding 1000ug/mL of bismuth standard solution into the volumetric flasks according to the amount of 1mL, 3mL, 5mL, 10mL, 25mL and 0.25mL, adding water to the 250mL scale lines of the volumetric flasks, and mixing all the substances in the volumetric flasks uniformly to obtain six standard solutions of a label A, a label B, a label C, a label D, a label E and a label F;wherein, the concentration of the indium element in the standard solution A is 4ug/mL, and the concentration of the bismuth element is 4 ug/mL;the concentration of indium element in the standard solution B is 20ug/mL, and the concentration of bismuth element is 12 ug/mL;the concentration of indium element in the standard solution C is 40ug/mL, and the concentration of bismuth element is 20 ug/mL;the concentration of indium element in the standard solution D is 120ug/mL, and the concentration of bismuth element is 40 ug/mL;the concentration of indium element in the standard solution E is 1ug/mL, and the concentration of bismuth element is 100 ug/mL;the concentration of indium element in standard solution F is 80ug/mL, and the concentration of bismuth element is 1 ug/mL.
- 4. The ICP-AES method for determining the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder according to claim 3, wherein in the step (3), the working parameters of the inductively coupled plasma atomic emission spectrometer are as follows:power: 1.0 KW-1.3 KW;plasma gas flow rate: 12L/min to 13L/min;auxiliary air flow rate: 1.0L/min-1.1L/min;flow rate of atomizing gas: 0.70L/min-0.85L/min;pump speed: 12rpm to 13 rpm;stabilization delay time: 10 s-12 s;sample lifting time: 10 s-13 s;reading time: 5s-6 s;the number of repeated measurements: 2 times to 3 times;observation height: 14 mm.
- 5. The ICP-AES method for determining the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder according to claim 4, wherein the method comprises the following steps: the analysis spectral line selected in the step (3) is a spectral line with high sensitivity and little interference; the analytical spectral lines of the selected bismuth and indium are as follows: bi 223.061nm and In 410.176 nm.
- 6. The ICP-AES method for determining the percentage content of bismuth and indium in the tin-indium-bismuth composite oxide powder according to claim 5, wherein the method comprises the following steps: in the step (4), besides the establishment of a method linear equation, the calculation of a correlation coefficient, a detection limit, a measurement lower limit and a relative standard deviation is also included; wherein, the correlation coefficient is more than or equal to 0.999, the detection limit is less than or equal to 0.010 percent, and the relative standard deviation is less than or equal to 1 percent.
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