Enhanced Hydrogen Evolution Reactions on Nanostructured Cu2ZnSnS4 (CZTS) Electrocatalyst

Publication date: 1 August 2017
Source:Applied Surface Science, Volume 412
Author(s): Renuka V. Digraskar, Balaji B. Mulik, Pravin S. Walke, Anil V. Ghule, Bhaskar R. Sathe
A novel and facile one-step sonochemical method is used to synthesize Cu2ZnSnS4 (CZTS) nanoparticles (2.6±0.4nm) as cathode electrocatalyst for hydrogen evolution reactions. The detailed morphology, crystal and surface structure, and composition of the CZTS nanostructures were characterized by high resolution transmission electron microscopy (HR-TEM), Selected area electron diffraction (SAED), X-ray diffraction, Raman spectroscopy, FTIR analysis, Brunauer−Emmett−Teller (BET) surface area measurements, Electron dispersive analysis, X-ray photoelectron spectroscopy respectively. Electrocatalytic abilities of the nanoparticles toward Hydrogen Evolution Reactions (HER) were verified through cyclic voltammograms (CV) and Linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and Tafel polarization measurements. It reveals enhanced activity at lower onset potential 300mV v/s RHE, achieved at exceptionally high current density −130mA/cm², which is higher than the existing non-nobel metal based cathodes. Further result exhibits Tafel slope of 85mV/dec, exchange current density of 882mA/cm², excellent stability (>500 cycles) and lower charge transfer resistance. This sonochemically fabricated CZTSs nanoparticles are leading to significantly reduce cell cost and simplification of preparation process over existing high efficiency Pt and other nobel metal-free cathode electrocatalyst.

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