Template synthesis of cobalt molybdenum sulfide hollow nanoboxes as enhanced bifunctional Pt-free electrocatalysts for dye-sensitized solar cells and alkaline hydrogen evolution

Due to the unique features including well-defined void space and high surface-to-volume ratio, non-noble metal catalysts with hollow structures have received intensive researches in dye-sensitized solar cells (DSSCs) and electrochemical water splitting. Herein, we prepare a series of cobalt-incorporated molybdenum sulfide hollow nanoboxes (denoted as Co-MoSx NBs) via a one-step fleet template conversion from cube-shaped Co-based zeolitic imidazolate framework-67 which precipitated without prolonged aged process. During above transformation, it is notable that the surface morphologies of nanobox can be effectively tailored by the proportion of MoS42-. The as-obtained Co-MoSx NBs with well-defined boxed structure and the appropriate doped ratio are developed as bifunctional catalysts for accelerating both reduction of I-3(-) in DSSCs and hydrogen evolution reaction (HER). As expected, a high power conversion efficiency (9.64%) is achieved by Co-MoSx-1/3 NBs based DSSC under AM 1.5G irradiation, which is much preceded to that of Pt (8.39%). Meanwhile, the practical utilization of Co-MoSx-1/3 NBs for HER yields a low onset overpotential (35 mV) and a small Tafel slope (61.4 mV decade(-1)) in alkaline medium. (C) 2018 Elsevier Ltd. All rights reserved.