CN115521780B - 一种煤基碳量子点及制备方法 - Google Patents
一种煤基碳量子点及制备方法 Download PDFInfo
- Publication number
- CN115521780B CN115521780B CN202211019821.0A CN202211019821A CN115521780B CN 115521780 B CN115521780 B CN 115521780B CN 202211019821 A CN202211019821 A CN 202211019821A CN 115521780 B CN115521780 B CN 115521780B
- Authority
- CN
- China
- Prior art keywords
- coal
- carbon quantum
- based carbon
- quantum dot
- quantum dots
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000003245 coal Substances 0.000 title claims abstract description 55
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 36
- 238000002360 preparation method Methods 0.000 title claims abstract description 7
- 238000000034 method Methods 0.000 claims abstract description 25
- 230000005284 excitation Effects 0.000 claims abstract description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 39
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical group [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 claims description 26
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 24
- 235000010288 sodium nitrite Nutrition 0.000 claims description 13
- 229910052759 nickel Inorganic materials 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 9
- 150000003839 salts Chemical class 0.000 claims description 7
- 238000001354 calcination Methods 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 6
- 239000012153 distilled water Substances 0.000 claims description 6
- 238000001914 filtration Methods 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 6
- 239000004570 mortar (masonry) Substances 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 6
- 239000007787 solid Substances 0.000 claims description 6
- 238000009210 therapy by ultrasound Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 4
- 238000009273 molten salt oxidation Methods 0.000 abstract description 6
- 230000035945 sensitivity Effects 0.000 abstract description 5
- 239000004065 semiconductor Substances 0.000 abstract description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 9
- 238000007254 oxidation reaction Methods 0.000 description 7
- 230000003647 oxidation Effects 0.000 description 6
- 239000002096 quantum dot Substances 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 229910052799 carbon Inorganic materials 0.000 description 4
- 238000005303 weighing Methods 0.000 description 4
- 239000002253 acid Substances 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000003917 TEM image Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 229910021393 carbon nanotube Inorganic materials 0.000 description 2
- 239000002041 carbon nanotube Substances 0.000 description 2
- 238000000295 emission spectrum Methods 0.000 description 2
- 229910021389 graphene Inorganic materials 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 229910003481 amorphous carbon Inorganic materials 0.000 description 1
- 238000001241 arc-discharge method Methods 0.000 description 1
- 239000003575 carbonaceous material Substances 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000000502 dialysis Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000006056 electrooxidation reaction Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000002189 fluorescence spectrum Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000001027 hydrothermal synthesis Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000004020 luminiscence type Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 230000005476 size effect Effects 0.000 description 1
- 150000003384 small molecules Chemical class 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 238000002371 ultraviolet--visible spectrum Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/65—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing carbon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/15—Nano-sized carbon materials
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/0883—Arsenides; Nitrides; Phosphides
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K9/00—Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as a result of excitation by some form of energy
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Nanotechnology (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biophysics (AREA)
- Optics & Photonics (AREA)
- Luminescent Compositions (AREA)
Abstract
本发明公开了一种煤基碳量子点及制备方法,其制备是以煤为原料,与氢氧化钠和亚硝酸钠混合,在高温下进行熔盐氧化,得到煤基碳量子点。该煤基碳量子点,在不同半导体激光激发下可以得到不同发射波长的可变色荧光。本发明利用廉价丰富的煤炭资源,以简单高效的熔盐氧化法,低成本、安全可控、可规模化制备出具有激发敏感、发光波长可调控且pH敏感的碳量子点。
Description
技术领域
本发明涉及煤基碳量子点的制备,以煤为原料,与氢氧化钠和亚硝酸钠混合,在高温下进行熔盐氧化,得到煤基碳量子点。研究结果表明由煤制备的煤基碳量子点,在不同半导体激光激发可以得到不同发射波长的可变色荧光。
背景技术
碳材料近几年受到人们的关注,如石墨烯、碳纳米管等,而碳量子点,一种新型的纳米材料是由无定形碳或者 sp2杂化碳组成,物理尺寸在 10 nm 以内,因其量子尺寸效应和边缘效应,在光电特性方面表现出优越的特性,相对于半导体量子点,碳量子点具有价格廉价、生物兼容性好、细胞毒性低、水溶性好等优点,在诸如生物成像、细胞传感、发光二极管、有机光伏器件、光催化和电催化等领域越来越受到人们的关注。
目前碳量子点的制备方法主要分为自上而下法和自下而上法。自上而下是指将尺寸较大的石墨、石墨烯、碳纳米管等切割成小分子而制备碳量子点的方法,例如电弧放电法、化学氧化法、电化学氧化法、水热法、电子束刻蚀法、超声剥离法等,自下而上是指小分子通过裂解,团聚等一系列化学反应得到颗粒更大的碳量子点再通过离心、透析等方法进行分离和提纯,主要指载体法、微波法等。其中常用的化学氧化法使用了浓硫酸、浓硝酸等强氧化性酸对环境的污染,容易产生污染,而且安全性低。
煤是自然界丰富而廉价的重要碳资源,主要由碳、氢、氧、氮、硫和磷等元素组成,碳、氢、氧三者总和约占有机质的95%以上,是非常重要的能源,也是冶金、化学工业的重要原料。目前用煤来制备碳量子点,主要采用强氧化剂的溶液化学氧化法。 溶液化学氧化法,强酸条件下超强的氧化条件使得反应过程安全性差,所以限制了工业化生产规模,另外强酸及强氧化剂对环境的危害影响大。 也有采用机械化学法的,但效率低,能耗高。
发明内容
本发明的目的是提供一种熔盐氧化法制备煤基碳量子点的方法。通过该方法,以煤为原料,与氢氧化钠和亚硝酸钠混合,在高温下进行熔盐氧化,得到的煤基碳量子点。该量子点在不同半导体激光激发可以得到不同发射波长的可变色荧光。其发光性能具有pH敏感性。
实现本发明目的的具体技术方案是:
一种煤基碳量子点的制备方法,特点是该方法包括以下具体步骤:
步骤1:将煤及熔盐置于研钵中,充分研磨0.5~1.5小时;其中,所述熔盐为亚硝酸钠和氢氧化钠;煤与熔盐的质量比为1∶10~30;亚硝酸钠与氢氧化钠的质量比为1~3∶1;
步骤2:将研磨后的混合物倒入镍坩埚中并至于马弗炉中,设置以3℃/min的升温速度,在150~300℃恒温煅烧1~5 h,待冷却至室温;
步骤3:将步骤2得到的固体中加入蒸馏水,超声30min,过滤得到颜色为淡黄色的澄清透明溶液,将淡黄色液体进行透析24小时,得到所述煤基碳量子点。
一种上述方法制备得到的煤基碳量子点,所述煤基碳量子点粒径为1~5nm;所述煤基碳量子点的荧光随激发波长变化而变化;所述煤基碳量子点具有pH值依赖性。
本发明采用熔盐氧化的方法,熔盐条件下合适的氧化条件和高效的氧化反应过程,安全性高,转化率高,效率高,成本低,而且可以保留煤基的多掺杂官能团,获得特殊荧光性能碳量子点。本发明利用廉价丰富的煤炭资源,以简单高效的熔盐氧化法,低成本、安全可控、可规模化制备出具有激发敏感、发光波长可调控且pH敏感的碳量子点。
附图说明
图1 为本发明煤基碳量子点的UV-vis光谱图;
图2 为本发明煤基碳量子点的TEM图;
图3 为本发明煤基碳量子点荧光光谱图;
图4 为本发明煤基碳量子点随荧光强度随pH值的变化图;
图5 为本发明煤基碳量子点的粒径分布图。
具体实施方式
实施例1
先称取0.5g的煤、5g亚硝酸钠和5g氢氧化钠,置于研钵中,手动充分研磨1h,将研磨后的混合物倒入镍坩埚中并至于马弗炉中,设置以3℃/min的升温速度,在150℃恒温煅烧5h,待冷却至室温,将所得到的固体中加入蒸馏水,超声30min,过滤得到颜色为淡黄色的澄清透明溶液,将淡黄色液体进行透析24小时,最后得到煤基碳量子点。该量子点的典型吸收光谱如图1所示。
实施例2
先称取0.5g的煤、5g亚硝酸钠和5g氢氧化钠,置于研钵中,手动充分研磨0.5h,将研磨后的混合物倒入镍坩埚中并至于马弗炉中,设置以3℃/min的升温速度,在250℃恒温煅烧0.5 h,待冷却至室温,将所得到的固体中加入蒸馏水,超声30min,过滤得到颜色为淡黄色的澄清透明溶液,将淡黄色液体进行透析24小时,最后得到煤基碳量子点,粒径分布在1~5nm。该量子点的典型透射电镜照片如图2所示。
实施例3
先称取0.5g的煤、5g亚硝酸钠和5g氢氧化钠,置于研钵中,手动充分研磨1.5h,将研磨后的混合物倒入镍坩埚中并至于马弗炉中,设置以3℃/min的升温速度,在200℃恒温煅烧3 h,待冷却至室温,将所得到的固体中加入蒸馏水,超声30min,过滤得到颜色为淡黄色的澄清透明溶液,将淡黄色液体进行透析24小时,最后得到煤基碳量子点。该量子点的发射光谱如图3所示。其发射光谱与pH值的关系如图4所示。
实施例4
先称取0.5g的煤、7.5g亚硝酸钠和2.5g氢氧化钠,置于研钵中,手动充分研磨1h,将研磨后的混合物倒入镍坩埚中并至于马弗炉中,设置以3℃/min的升温速度,在300℃恒温煅烧1 h,待冷却至室温,将所得到的固体中加入蒸馏水,超声30min,过滤得到颜色为淡黄色的澄清透明溶液,将淡黄色液体进行透析24小时,最后得到煤基碳量子点。该量子点的粒径分布如图5所示。
Claims (2)
1.一种煤基碳量子点的制备方法,其特征在于,该方法包括以下具体步骤:
步骤1:将煤及熔盐置于研钵中,充分研磨0.5~1.5小时;其中,所述熔盐为亚硝酸钠和氢氧化钠;煤与熔盐的质量比为1∶10~30;亚硝酸钠与氢氧化钠的质量比为1~3∶1;
步骤2:将研磨后的混合物倒入镍坩埚中并至于马弗炉中,设置以3℃/min的升温速度,在150~300℃恒温煅烧1~5 h,待冷却至室温;
步骤3:将步骤2得到的固体中加入蒸馏水,超声30min,过滤得到颜色为淡黄色的澄清透明溶液,将淡黄色液体进行透析24小时,得到所述煤基碳量子点;所述煤基碳量子点粒径为1~5nm;所述煤基碳量子点的荧光随激发波长变化而变化;所述煤基碳量子点具有pH值依赖性。
2.一种权利要求1所述方法制备得到的煤基碳量子点。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202211019821.0A CN115521780B (zh) | 2022-08-24 | 2022-08-24 | 一种煤基碳量子点及制备方法 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202211019821.0A CN115521780B (zh) | 2022-08-24 | 2022-08-24 | 一种煤基碳量子点及制备方法 |
Publications (2)
Publication Number | Publication Date |
---|---|
CN115521780A CN115521780A (zh) | 2022-12-27 |
CN115521780B true CN115521780B (zh) | 2023-12-01 |
Family
ID=84697019
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202211019821.0A Active CN115521780B (zh) | 2022-08-24 | 2022-08-24 | 一种煤基碳量子点及制备方法 |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN115521780B (zh) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109019560A (zh) * | 2018-10-16 | 2018-12-18 | 吕梁学院 | 一种煤基碳点的制备方法 |
-
2022
- 2022-08-24 CN CN202211019821.0A patent/CN115521780B/zh active Active
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109019560A (zh) * | 2018-10-16 | 2018-12-18 | 吕梁学院 | 一种煤基碳点的制备方法 |
Non-Patent Citations (2)
Title |
---|
A high-yield and versatile method for the synthesis of carbon dots for bioimaging applications;Li Liping;《Journal of Materials Chemitry B》;第5卷(第10期);摘要,第1936页左栏倒数第1段,第1935页右栏第2段 * |
煤基碳量子点合成研究进展;薄纯辉;《应用化学》;第38卷(第7期);表1,第780-781页第2.1.1.2小节 * |
Also Published As
Publication number | Publication date |
---|---|
CN115521780A (zh) | 2022-12-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Wang et al. | Recent progress in gC 3 N 4 quantum dots: Synthesis, properties and applications in photocatalytic degradation of organic pollutants | |
Yao et al. | Carbon dots based photocatalysis for environmental applications | |
Wang et al. | Emerging carbon-based quantum dots for sustainable photocatalysis | |
Cao et al. | Cobalt phosphide as a highly active non-precious metal cocatalyst for photocatalytic hydrogen production under visible light irradiation | |
CN108190859B (zh) | 一种金刚石型碳量子点和制备方法及其应用 | |
CN109437154B (zh) | 一种以煤为原料制备能带可控碳量子点的方法 | |
CN102602924B (zh) | 微波辐射法制备双色石墨烯量子点的方法 | |
CN113663693B (zh) | 一种硫化铟锌-二氧化钛复合材料的制备方法及其在生产双氧水用于废水治理中的应用 | |
CN103191766A (zh) | CdS/g-C3N4复合可见光催化剂、制备方法及应用 | |
CN105417507A (zh) | 一种氮化碳纳米颗粒的制备方法及所得产品 | |
CN106902803B (zh) | 复合型光催化体系CQDS-KNbO3及其制备方法和应用 | |
CN113145138B (zh) | 热响应型复合光催化剂及其制备方法和应用 | |
CN103861618A (zh) | 一种SnO2基复合可见光光催化剂的制备方法 | |
CN115007182B (zh) | 一种钾氧共掺杂石墨相氮化碳光催化剂的制备方法 | |
CN103113887A (zh) | 一种结构及荧光可控含氮石墨烯量子点复合微粒的制备方法 | |
Hou et al. | Application of coal-based carbon dots for photocatalysis and energy storage: a minireview | |
CN105110554B (zh) | 一种耦合(光)催化与mfc去除水中硝酸盐氮的系统 | |
Shao et al. | Hydrothermal synthesis of ZnO quantum dot/KNb3O8 nanosheet photocatalysts for reducing carbon dioxide to methanol | |
CN109395759B (zh) | 一种具有核壳结构的Fe3C纳米粒子及其制备方法和应用 | |
CN115521780B (zh) | 一种煤基碳量子点及制备方法 | |
CN113120977B (zh) | 由含镍铁电镀废水制备铁酸镍纳米材料的方法及应用 | |
CN110615470A (zh) | 一维金属掺杂金红石二氧化钛纳米线及其制备方法 | |
CN109433246B (zh) | 含有碳空位的纳米片c3n4光催化剂及制备方法 | |
Shandilya et al. | An overview of synthesis and photocatalytic application of carbon quantum dots-based nanocomposites | |
CN108394886B (zh) | 一种基于强碱切割氧化石墨制备碳量子点的方法、其产品及应用 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |