Enhanced Hydrogen Evolution Activity via Visible-Light-Driven Ag/MoS 2– x -Modified p-Type Si Micropyramid Cells with Optimized Band Alignment
Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Hydrogen is a clean energy carrier with the potential to address current environmental and energy challenges. One promising approach to hydrogen production is through photoelectrocatalytic water splitting, which utilizes solar energy with a minimal external bias. To improve the cell efficiency in evolving H 2, a MoS 2– x @Ag heterostructure was integrated on a micropyramidal p-type silicon (p-Si) substrate to form a photocathode with optimized band alignment. The cell was prepared by a sputtering method. The structural, compositional, and electronic properties of the photocathodes with varying layer thicknesses were characterized by using XRD, SEM, XPS, UPS, LEIPS, LSV, and PL techniques. The p-Si/MoS 2– x /Ag heterojunction exhibited a favorable band structure for efficient charge transfer, facilitating electron accumulation for hydrogen evolution. Optimal photoelectrocatalytic performance was achieved with 50 nm MoS 2– x and Ag layers, yielding a photocurrent density of 6.5 mA/cm 2 at 0 V RHE . Beyond band alignment, surface defects also played a significant role in enhancing the activity by suppressing photocarrier recombination. XPS analysis revealed a high concentration of Mo 6+ at the interface, indicating the presence of Mo antisite defects, which are beneficial for charge transport and catalytic efficiency. This work presents a practical design strategy that leverages both band engineering and defect modulation to improve the performance of photocathodes for solar-driven hydrogen production.
Source: ACS Applied Energy Materials
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Award: G7774865376
OpenAlex ID: W4413227153