Polyvinylpyrrolidone-assisted novel copper antimony sulfide nanorods for highly efficient hydrogen evolution reaction

[Display omitted] •PVP assisted CuSbS2 exhibited 40.37 m2/g elevated surface area.•0.5 g PVP-CuSbS2 explored 177 mV to attain 10 mA/cm2.•0.5 g PVP-CuSbS2 (187 mV/dec) was smaller than pure and 1.0 g PVP-CuSbS2.•0.5 g PVP-CuSbS2 has high intrinsic activity and excellent durability in long-term i-t test. Transition metal dichalcogenides have been the most attractive material in hydrogen evolution reaction due to their advantages such as being cost-effective, earth-abundant, excellent conductivity, etc. In this study, PVP-assisted CuSbS2 nanorods were produced via hydrothermal technique. In XRD spectra, high intense peak at 28.34, 28.64, 29.54 and 29.80° clearly divulged CuSbS2 phase. The synthesized products Raman spectra also confirmed the existence of pure orthorhombic phase CuSbS2. The surface morphology of CuSbS2 has been studied by scanning electron spectroscopy, which displayed the 1D nanorod morphology and it is further confirmed by the TEM images. The elemental composition of the synthesized products is also characterized by the EDX mapping and EDX spectra, which shows the homogenous distribution of elements such as Cu, Sb and S in proper atomic percentage of 27.16, 21.06 and 51.78 respectively. Compared to the excess amount of PVP assisted CuSbS2, optimum amount of PVP assisted CuSbS2 exhibited 40.37 m2/g elevated surface area. The required over potential for 0.5 g PVP-CuSbS2 is only the 177 mV to attain 10 mA/cm2. Moreover, Tafel value of 0.5 g PVP-CuSbS2 (187 mV/dec) was smaller than pure (241 mV/dec) and 1.0 g PVP-CuSbS2 (219 mV/dec). The estimated turnover frequency (TOF) also showed that 0.5 g PVP-CuSbS2 has high intrinsic activity and exhibited excellent durability with 90.6% retention in long-term i-t test. Moreover, the catalytic activity of 0.5 g PVP-CuSbS2 was also high, which exhibited the Cdl and ECSA value of 115.3 mF/cm2 and 5.76 cm2 respectively. Therefore, the ternary metal chalcogenide revealed capable superior stability for hydrogen evolution reactions.