Photovoltaic Performance Of Polyoxometalates/Phthalocyanine Composite Film

Due to energy shortage and environmental pollution is serious,the use of solar energy and solve the problem of pollution has become a hot spot of chemical research.Polyoxometalates(POMs)as excellent electron acceptor,because can capture other electronic semiconductor material,reduce the composite of electrons and holes in composite material,so can.Phthalocyanine as a kind of high efficiency,and has a very strong absorption in the uv-vis absorption spectra of sensitizing agent,the price is low,the preparation is convenient.Taking more acid and the advantage of phthalocyanine,based on different acid structure,the preparation of the series more acid/phthalocyanine composite film electrodes,and studied the photoelectric conversion efficiency composite membrane electrode and catalyst efficiency,gas sensing.Specific as follows:1.We made a simple dye-sensitised cells,with copper(II)phthalocyanine dyes(CuPc)as a sensitizer,polyoxometalates as electron transport materials,including three kinds of POMs,Keggin,Dawson,metal-substituted Keggin as electron transport materials.Through i-v curve test(J-V),electrochemical impedance test(EIS),the open circuit voltage decay test curve measurement(OCVD),we explained the photoelectric anodic resistance and electron hole composite dynamics/electrolyte interface.Our research focuses on electron transfer properties of pure POMs,in the absence of any titanium dioxide or other metal oxide semiconductor.Experiment proves pure POMs can have electronic transmission function.And we discussed the different structures and different metal-substituted POMs as electron transport materials.The experimental results show that: the electronic transmission capacity of Dawson type POMs is higher than Keggin type.In addition,the electronic transmission ability of the series containing tungsten POMs were better than molybdenum series POMs,while the electronic transmission ability of titanium replace Keggin type was most weak.2.FePc/PW11 Fe film was prepared by infrared(ir)and energy spectrum test,can determine the composite film contained FePc and PW11 Fe structure.We through four aspects discussed catalytic efficiency of phenol of the FePc/PW11 Fe film.First,we determined the molar ratio of catalyst,the highest catalytic efficiency of the mole ratio is: FePc/PW11 Fe = 0.1:0.5.the maximum degradation rate was about 11.5%.Later,we discussed the concentration of supporting electrolyte catalytic efficiency of phenol,when the electrolyte concentration is 0.50 mol/L,the phenol degradation rate is at its maximum(19%).Then,we studied the phenol solution of different concentrations of phenol degradation rate,when the initial concentration of phenol solution was 10 mg/L,the phenol degradation rate was about 38.5%.Finally,we applied different applied voltage(0 V,0.2 V,0.4 V,0.2 V),photoelectric catalysis experiment of phenol solution structure of experiment has shown that under the condition of the applied voltage of 0.6 V,catalytic efficiency can reach 65%.After the four aspects of the experiment,we can found that under the molar ratio of the FePc/PW11 Fe film was(0.1:0.5),with concentration was 0.50 mol/L Na2SO4 as electrolyte solution,plus 1.0 m L H2O2(30%),catalytic concentration phenol solution was 10 mg/L,and bias of 0.6 V,maximum photoelectric catalysis efficiency can achieved 65%.3.Through the simple coating method,we preparated CuPc/POMs photoconductive materials,including more than two structures of POMs type: Keggin(PW12),Dawson(P2W18),through the i-v curve test and the time-current test to explored the photoconductive properties of different POMs.Time-current test showed that the photocurrent density of the P2W18/ CuPc photoconductive devices is greater than the PW12/ CuPc photoconductive devices.This was mainly due to the different light raw carrier density of different POMs,and the separation of the light carrier of composite was different,which affect the photoconductive properties of POMs.In addition,we use ed P2W18/CuPc photoconductive devices for ethanol gas sensitive performance test,the experimental results show that P2W18 / CuPc device has good gas sensitive should be on ethanol gas,the detection limit was less than 25 PPM.