Sn4+-driven block-to-flower topological transformation in defect-rich In2S3 enabling efficient photocarrier migration

Sn-doped In 2 S 3 nanoflowers were synthesized via a facile hydrothermal route. • Sn incorporation enables synergistic modulation of electronic and carrier dynamics. • The rapid charge recombination in pristine In 2 S 3 was effectively suppressed. • A markedly enhanced H 2 evolution rate of 9.135 mmol/g/h was achieved. The severe charge-carrier recombination and sluggish migration kinetics fundamentally restrict the photocatalytic efficiency of transition-metal chalcogenides. Herein, we demonstrate a multiscale dual-engineering strategy to synergistically modulate the geometric and electronic structures of In 2 S 3 via Sn incorporation. The heteroatom doping not only triggers a topology-directed morphological transformation from disordered bulk blocks to hierarchical nanoflowers, but also introduces localized defect states near the conduction band. Mechanistic and kinetic analyses reveal that these defect states act as electron-trapping centers, which cooperatively couple with the morphology-guided shortened diffusion pathways to facilitate spatial charge separation and mitigate bulk recombination. Consequently, the optimally Sn-doped In 2 S 3 photocatalyst delivers a robust H 2 evolution rate of 9.135 mmol/g/h, representing a 16.9-fold enhancement relative to the pristine counterpart. This work establishes a rational paradigm for coupling topological reconfiguration with defect-mediated electronic modulation to design highly efficient solar-to-chemical conversion systems. Download: Download high-res image (80KB) Download: Download full-size image