Designing metal sulfide sphere counter electrode catalysts for ZnO nanorod array based quantum dots-sensitized solar cells

To increase the competitiveness of quantum dots-sensitized solar cells (QDSCs) among various photovoltaic devices, it is necessary to develop new counter electrode (CE) catalysts to replace traditional expensive Pt CE. Herein, a series of metal sulfide spheres (e.g. FeS2, Co9S8, NiS, CuS, and ZnS) are designed and synthesized as CE catalysts for QDSCs. As inferred from cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization curves results, except ZnS, all of the sulfide spheres perform better than Pt toward Sx2-/S2- redox couple regeneration, among of which NiS shows the highest catalytic activity, followed by Co9S8, CuS, and FeS2. The power conversion efficiencies of ZnO nanorod arrays photoanode based QDSCs with sulfides sphere CEs are 2.45% (NiS), 2.17% (Co9S8), 1.83% (CuS), and 0.80% (FeS2), much higher than that of Pt CE based counterpart (0.30%).

from #ENT-AlexandrosSfakianakis via ola Kala on Inoreader http://ift.tt/2u7TgYC