Enhancing the Performance of Bi ₂ S ₃ in Electrocatalytic and Supercapacitor Applications by Controlling Lattice Strain

Lattice-strained Bi2S3 with 3D hierarchical structures are prepared through a top-down route by topotactic transformation. High-resolution transmission electron microscopy and X-ray diffraction (XRD) confirm the lattice spacing is expanded prolonged sulfuration. Performance studies demonstrate that largest expansion (Bi2S3-9.7%, where 9.7% represents expansion) exhibits greater electrocatalytic hydrogen evolution reaction (HER) activity compared to Bi2S3-3.2%. Density functional theory calculations reveal of reduces bandwidth upshifts band center Bi 3d orbits, facilitating exchange S 2p orbits. The resultant intrinsic electronic configuration favorable H* adsorption kinetics reduced energy barrier for water dissociation in evolution. Operando Raman post-mortem characterizations using XRD photoelectron spectroscopy generation pseudo-amorphous at edge nanorods sample strain during HER, yielding Bi2S3-9.7%-A. It worth noting when Bi2S3-9.7%-A assembled as positive electrode an asymmetric supercapacitor, its performance greatly superior same device formed pristine Bi2S3-9.7%. as-prepared Bi2S3-9.7%-A//activated carbon supercapacitor achieves high specific capacitance 307.4 F g−1 1 A g−1, exhibiting retention 84.1% after 10 000 cycles.