Preparation And Performance Of Inorganic/Conductive Polymers Nano-composite Counter Electrodes

The counter electrode(CE) is very important in the DSCs beacause it can collectexternal electronic and high catalytic activity. Pt is widely used in DSCs as thecounter electrode because of its good photoelectric performance. However, Pt counterelectrode goes against its industrialization and low cost with the problem of high cost.Therefore, looking for the new type of counter electrode in replace of Pt counterelectrode becomes a research hotspot. This article uses polyaniline and PEDOT:PSS with five kinds of inorganic materials (including mesoporous carbon, activatedcarbon, graphite, carbonized wood and nano TiO2) composite construct three kinds ofcomposite electrode, namely carbon/PANI composite electrode, carbonizedwood/PEDOT:PSS composite electrode and TiO2/PEDOT:PSS composite electrode.Through the impedance (EIS) and cyclic voltammograms (CV) and Tafel polarizationcurve, scanning electron microscopy (SEM) analysis method, This article analyzesthe three kinds of compound catalytic activity of the electrode and the photoelectricproperties of DSCs, and discusses the internal reason of dominate the photoelectricproperties.Studies have shown that:The conversion efficiency (η) has a parabolic variation with graphite content inthe graphite/PANI composite counter electrode. The improvement of the efficiency isdue to good electrical conductivity of graphite and the microporous structure ofpolyaniline. In addition, Nickel nanoparticles in graphite/PANI composite counterelectrode can make the photoelectric performance degradation.In three kinds of carbide wood counter electrodes, buttonwood counter electrodeon the performance is the best,and the conversion efficiency is as high as4.63%.After spinning aqueous solution of PEDOT:PSS on the carbide wood counterelectrodes, carbonized bamboo/PEDOT:PSS composite counter electrode improvesefficiency, the conversion efficiency from2.07%to2.76%.The counter electrode performance becomes worse and worse with the spinspeed increasing in the preparation of TiO2/PEDOT: PSS counter electrode. When thespin speed is2000r/min, electrochemical performance of the counter electrode is the best, and the conversion efficiency of DSCs is as high as4.57%. As the concentrationof PEDOT:PSS aqueous solution is increasing in the TiO2/PEDOT:PSS compositecounter electrode, the electrochemical properties of counter electrode become better.When the concentration of PEDOT:PSS aqueous solution is1.3wt%, theelectrochemical performance of the counter electrode is best, and the conversionefficiency of DSCs is as high as5.381%.As the SnO2content is increasing in theTiO2/PEDOT:PSS composite counter electrode, the conversion efficiency of DSCsfirst increases then decreases.When SnO2content is more than40%, the conversionefficiency decreases. When SnO2content is between10%and40%, the conversionefficiency is stable at around6.5%.