Bimetallic NiCoP nanoparticles incorporating with carbon nanotubes as efficient and durable electrode materials for dye sensitized solar cells

In this research, the bimetallic NiCoP nanoparticles and NiCoP/carbon nanotubes (CNTs) composites were successfully synthesized, and their performances as counter electrodes (CEs) for dye sensitized solar cells were investigated. The optimal composite CE (NiCoP-CNTs-3) exhibits outstanding photoelectric conversion efficiency (PCE) of 7.24%, which exceeds the single NiCoP (4.71%) or CNTs electrode (6.05%) and is on par with the standard Pt CE (7.12%) under same conditions. The electrochemical properties of NiCoP-CNTs electrodes were also characterized by utilizing the electrochemical impedance spectroscopy (EIS), Tafel polarization curves and cyclic-voltammetry (CV). The results indicate that NiCoP-CNTs-3 electrode holds Pt-like good electrocatalytic activity towards reduction of I-3(-). In addtion, the composite CE shows a reliably electrochemical stability. The present materials in this study may pave a way for the practical applications of Pt-free DSSCs. (C) 2019 Elsevier B.V. All rights reserved.