JPS60189877A - Polymer metal complex film covered photo response electrode - Google Patents

Abstract

PURPOSE:To give an electrode desired photo respose property by covering the surface of conductive material with the film of polynuclear metal cyanocomplex obtained from metal salt of VIII group and hexacyanocomplex salt of VIII group metal. CONSTITUTION:Polynuclear metal cyanocomplex is obtained from a salt of VIIIgroup metal such as Fe and a hexacyanocomplex of VIII group metal, for example, from the equimolar mixture solution of ferric chloride and potassium ferricyanide. A working electrode comprising conductive material, a counter electrode, and a reference electrode are immersed in the cyanocomplex solution, and the working electrode is set to a specified potential and a film of polynuclear metal cyanocomplex is fomed on the electrode. This electrode is used as photoresponse electrode. According to circumferences, the upper layer or the lower layer of this film is convered with a polymer film of tris(2,2'-bipyridine)ruthenium (II) complex. When light is irradiated on the surface of this film, photocurrent is obtained depending on electrode potential.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention applies electrons to an ex-responsive ζ pole formed by coating a film of a polynuclear metal cyano complex.

The present inventors conducted intensive research on various metal complexes from the viewpoint that by coating the electrode surface with a metal complex that causes an electron transfer reaction in a photoexcited state, it is possible to impart a photoresponsive function to the electrode. . As a result, the present inventors discovered that it is possible to easily coat an electrode surface with a stable film of a polynuclear current metal cyano complex, leading to the completion of the present invention.

The present invention provides a film of a polynuclear metal cyano complex obtained from a salt of a metal M in group 1 of the periodic table and a hexane ano complex salt of a metal M2 in group %'jll of the periodic table on the surface of a conductive material. It is a photoresponsive electrode formed by coating.

The present invention provides a photoresponsive electrode comprising a layer of a polynuclear metal cyano complex and a polymer film of a tris(42'-bipyridine)ruthenium(II) complex layered on the surface of a conductive material. It is. The polymer film of tris(2,2'-bipyridine) ruthenium (■) @ acts as an upper or lower layer (i.e., a film of a polynuclear metal cyano complex) with respect to a film of a polynuclear gold A.]17ano complex. It may be formed anywhere (between the electrodes). By coating with two types of films in this manner, a larger photocurrent can be extracted.

M□ and M2 may be metals from group Ⅰ of the periodic table, and may be the same or different.

Typical examples of Myu and M2 are hb, RU.

In the present invention, a polynuclear metal cyano complex means a complex in which a large number of metal ions of the same type or different types are alternately connected via cyano ligands. Such a polynuclear metal cyano complex is made of a salt of a metal M selected from group Ⅰ and a metal cyano complex selected from group Ⅰ.
Metal M selected by the T family.

can be easily formed by mixing approximately equimolar aqueous solutions of the hexacyano complex salts of .

By immersing a conductive material, that is, a working electrode, a counter electrode such as platinum, and a reference electrode in this aqueous solution and applying a reduction potential or an oxidation potential to the working electrode, a polynuclear metal cyano complex (sample) is deposited on the working electrode. This can be explained as follows using a typical polynuclear iron cyano complex as an example.

When a ferric salt such as ferric chloride is mixed with an equimolar aqueous solution of potassium ferricyanide (ni3[h3+(CN)6]), a polynuclear metal cyano complex of I"n"-FalIIIJ is formed. In this complex aqueous solution, a working electrode,
The counter electrode and reference electrode are immersed, and the working electrode is placed at a potential of -〇, SV.
(vs, Ag-Agα reference electrode),
On the surface of the working electrode, the II-, .ill-type complexes are reduced to hIII-1tII-type complexes, and at the same time, this complex is deposited on the surface of the working electrode to form a film. By the way, VC Co.'s Pb"-F,'a" type polynuclear iron cyano complex is called Gurung Amp Blue (hereinafter abbreviated as Pa).
Its composition is expressed as Fag'' [Fa■(CN)6per. The crystal structure of the unit cell of PB is shown in the attached drawing. The polynuclear metal cyano complex used in the present invention has 4 units of It has a structure in which many are connected together.

The thickness of the polynuclear metal cyan inscription film is suitably between θA and θμm. When electrodepositing a complex film on a working electrode from an aqueous solution of a polynuclear cyano complex, it is preferable to dissolve an electrolyte such as potassium sulfate or potassium chloride in the aqueous solution, since this improves the efficiency of electrodeposition.

As shown in the above example, high valence M-
When using an aqueous solution of a polynuclear metal cyano complex of M, concave type (metal ions of different or similar metal ions), a reduction potential is applied to the working electrode. A polynuclear metal cyano complex film of the M□■-M2■ type is deposited on the working electrode. What is the potential at that time? 10.3
V ~-/OV (vs, Ag -Age/) as appropriate. Also, as a raw material, low valence M□ −M2■
When an aqueous solution of &j■ type is used, an oxidation potential is applied to the working electrode to precipitate a polynuclear metal cyano-forming film of Mn+M21 or Mn-M2m type on the working electrode. The potential at that time is 0.7 V ~/OV (vs, Ag
-AEI! α) is appropriate. Usually, a M□-M2■ type complex may be used as a raw material.

What kind of 4@ as the working electrode used in the present invention?
Although the electrode may be made from a carbonaceous material, carbon electrodes are preferable from an economical point of view.

After washing the membrane of the polynuclear 2-metal cyano complex produced in this way with water, the coated working electrode, counter electrode, and reference electrode (Ag-Agα) were washed in water or in 1-antpotassium sulfate or potassium chloride. When the working electrode is immersed in water containing a dissolved electrolyte, an appropriate potential is applied to the working electrode, and light is irradiated onto the surface of the coating, an original current is generated. The current flows repeatedly and reversibly depending on the original irradiation and interruption) °C. ) The direction of the YS current depends on the electrode potential, o V (vs, p, a,
Below -A (2Ct), it becomes a cathode photocurrent, and above 0.2V, it becomes an anode photocurrent.

As a light source, any visible 5'll will do, such as sunlight or white? A fluorescent lamp, a projector, a xenon lamp, a Lele 9-e, etc. are used.

) The zero response amount (value of photoelectricity 1 and r) is significantly increased by oxidizing the redox reagent and dissolving the quaternary form in water. For the oxidized and reduced forms of redox reagents, for example 2+ to /-73ν.

Metal ions such as Cu2+/C+-+1+, Pb"/Pb"+, Fa(CN)/FA(Cro3-,
n (lIl) ethylenediaminetetraacetic acid chelate/iron (If) ethylenediaminetetraacetic acid chelate, Co (N
H3) 6α2+/Co (NH3), metal complexes such as α1+, +2/l;, halodane systems such as α2/α-,
Examples include organic compounds such as fluorine/hydrogenone and ascorbic acid/dehydroascorbic acid.

The present invention also provides an upper or lower layer of the polynuclear metal cyano complex film, that is, between the film and the electrode ((, Tris(, 2
,,2'-BibiliCkun) Lupnium (II) A photoresponsive 7Ct electrode coated with a polymer film is provided. The tris(λ'-bivirinone)runonium complex (hereinafter RU(1)py), abbreviated as "+", causes a redox reaction of glue in the photoexcited state.
)3"" cannot be used alone as a film, but if a synthetic island molecular material is used, it can be coated as a film, and Ru(t)p,)3"+ in this film is in its photo-excited state with one adjacent A redox reaction occurs with one polynuclear metal cyano, which is a membrane component, and this is reflected in the electrode response, increasing the original current. (sodium chloride), or formula (1): % formula % (Tasso X is the number of 0 x A polyanionic polymer material (for example, Bonafion (registered trademark) manufactured by DuPont) that supports the backing unit is cast by a casting method, but if it is not easy to use, ,R,,(
b, y) This is carried out by forming a polymer having a 3"+ complex structure into a film by a casting method.

[Formula ``rN to I'J c は目' - Chatter: Kunderari,
×(1θ×≦/, y!j, 0≦y(/andθ×x+y
≦/C exists. A is a copolymer unit; ;'Hi and Zu I=
-f Styrene In this way, a polymer film of Ru(j'py)3''+ can be formed on the working electrode coated with a film of polynuclear metal cyan A-body.

On the other hand, between the polynuclear metal cyano complex film and the working electrode, NiRU (
bpy) 3'+ To form a polymer film, action 'ii
After forming a Ru(bpy)32+ polymer film on the J electrode in advance by a casting method, the polynuclear metal cyano complex film can be electrophased using this coated electrode as a working electrode.

RU(b,y)3'+ The thickness of the polymer film is HirooA~10
μm is appropriate.

The present invention will be explained below with reference to an embodiment of the tone plate.

Examples/~5 Ferric chloride - 0mM aθ/M-Hα aqueous 10- and potassium ferricyanide 20mM o,oiM-
Hα aqueous solution/(7ml) When mixed, Fn -F
≧ type polynuclear iron cyano complex (P/l/IJ 7 f
A water bath solution (referred to as lean) is immediately obtained. A rod-shaped carbon electrode (7427 surface area is 0, /7
c,! ), Yamajaku pair, 1 year old (/all), and AjJ-/Jαnorsho'+fi, etc. are immersed in carbon electrodes and applied with 10, S V (vs, Ag-Aet2)k, and solcian is deposited on the electrodes. Blue (Pa', Fn" -
A film of pH2'-type complex) is deposited.

After electrolysis for 300 seconds, the coated electrode is taken out and water is ≥1.

This PB his love carbon'jij, kite, platinum counterpole, and Ag
-8gα When the reference electrode was immersed in an aqueous solution of 0.5M potassium sulfate and the surface of the coating film was irradiated with light from a ho0w xenon lamp 0, a photocurrent was obtained depending on the electrode potential. The photocurrent values are shown in Table/.

Table/Example B In Example/, potassium ferricyanide and potassium ferrocyanide were each added at 0.0% in place of the 2So4 aqueous solution.
When light irradiation was performed in the same manner using aqueous solutions containing 1M each, the cathode photocurrent was /gua μA/d at the electric potential ov, and /77 /J A/cr at 0.5■.
An anodic photocurrent of A was obtained.

Example 7 In Example B, the same operation as in Example 6 was performed except that ferric chloride and ferrous chloride were used instead of potassium ferricyanide and potassium ferrocyanide.
In ■, the anode photocurrent of g1gμA/d is -〇, 3v
In this case, a cathode photocurrent of 1.5 g/μA/cJ was obtained.

Example g In Example 7, when iodine and potassium iodide were used as substitutes for ferric chloride and ferrous chloride and sunlight was irradiated, an anode photocurrent of 3/μA/cJ at -0, 3V was obtained. was gotten.

Examples Ruthenium chloride') A (llll) 20 tn M +
7) 0.07 M-H01 water n solution/θ- and 20 mM potassium ferricyanide. When θ/M-Hα aqueous solution/θ- is mixed, an /ik3''-Ru type polynuclear cyano complex aqueous solution is obtained.

A platinum working electrode (/6It) and a platinum counter electrode (/6It) were added to this aqueous solution.
cr & ) and Ag-A8α reference electrode and apply one coat to the platinum working electrode, FX ” -R appears on the electrode.
A u 2+ -type polynuclear complex (called ruthenium couple) is precipitated. After performing electrolysis for 700 seconds, the covered electrode is taken out and washed with water.

This coated platinum working electrode, platinum counter electrode, and AQ-Agα
The reference electrode was immersed in a 7M potassium chloride water bath, and the
When the film surface was irradiated with light from a halogen lamp for a projector, a cathode photocurrent of 2 μA/d was obtained at an electrode potential of 0 μ/d.

Examples 70-/2 On the PB film of the carbon electrode coated with the Pa film by the method of Example A solution of the mold cylinder molecule complex in methylformamide (DMF) (e degree is 26 my/min for the sample)
/tntDMF) 0. Place it on a gμt2 microsyringe, spread it evenly, dry it, and add polymer Ru (
A film of bp, )32+ was formed.

When irradiation was carried out using this two-layer coated electrode in the same manner as in Example 1, a photocurrent as shown in Table 1 was obtained.
is.

Table 1 Example 1 / 3 to 15 Same as Example 1, using the two-layer coated electrode in Example 10 and using an aqueous solution containing 0.7 M each of ferric sulfate and ferrous sulfate. When irradiated with light, photocurrents as shown in Table 3 were obtained.

Table 3 Example/Otsu rod-shaped carbon electrode (disc surface area 0./'7 ca
l On the surface, 2 μt of Nafion (registered trademark) dimethyl sulfoxide/ethanol = /// (V, /V, mixed solvent solution <o, s6% by weight) was placed on the surface using a microsyringe, spread and dried, All Nafio 7 membranes were formed. This Nafion membrane-coated electrode is RU(6p,)X
+'c/m When immersed in 41 liquids of water containing M, RL
l(b,,)3"" is incorporated into the ion film,
R, (bp,) 3"+ film-covered electrode is formed. The different surface of this covered electrode is coated with a PB film in the same manner as in Example/, to create a two-layer coated electrode. On the surface of this 10 When light was irradiated in the same manner as in Example B, an anode photocurrent of S/θμA/cA was obtained at Ov, and an anode photocurrent of 130μA/cJ was obtained at /■.

[Brief explanation of the drawing]

The attached drawings show the structure of a crystal unit cell of a j□'n''-h,'' type polynuclear cyano complex (Prussian blue).・Fe” 0Fe2+

Claims (1)

[Claims] (/') A film of a polynuclear metal cyano complex obtained from a salt of a metal M of Group I of the Periodic Table and a hexacyano complex salt of a metal M2 of Group S'll of the Periodic Table. A photoresponsive electrode made by coating the surface of a conductive material. (,2) Claim 1 in which M yu and M2 are h
Electrode as described in Section. (,1) The electrode according to claim 1, wherein M□ is RUXM2 is h. (lA) A film of a polynuclear metal cyano complex obtained from a salt of the genus M□ of group ν ill of the periodic table and a hexacyano complex salt of genus M2 of group Vllll of the periodic table, and tris(2゜A photoresponsive electrode formed by coating the surface of a conductive material with a polymer film of a ruthenium (n) complex (2'-biviricin).
The electrode according to claim 1, wherein the electrode is coated with a polymer film of a 2'-biviricin y ruthenium (II) complex. (θ There is a tris holo′ in the lower layer of the polynuclear metal cyano complex film.
8. The electrode according to claim 7, wherein the electrode is coated with a polymer film of a ruthenium (II) complex. (7) The electrode according to claim 1, 3, or 3b, wherein M and M2 are h. (g) 'Iu, pole according to claim j or claim 3 or stripe claim 6, wherein M□ is Ru and M2 is h.