Abstract
Achieving solar-to-hydrogen (STH) conversion efficiencies above 10 % is within reach with silicon carbide (SiC), a wide-bandgap semiconductor offering unique properties for photoelectrochemical (PEC) water splitting. This review integrates recent advances in novel van der Waals heterostructure designs, Janus-based SiC composites, and eco-friendly synthesis routes to improve efficiency and scalability. In addition, it provides a systematic correlation of density functional theory (DFT) predictions with experimental performance metrics, highlighting critical gaps and optimization pathways. Additionally, comprehensive modeling of electronic structures, band alignments, and surface reactions to optimize SiC-based configurations, including type-II heterojunctions with materials such as MoS 2 and TiO 2 . Key performance metrics, such as photocurrent density and STH efficiencies, are evaluated alongside experimental advancements. Despite significant progress, challenges such as long-term photoelectrode stability, scalable fabrication, and cost reduction persist. We discuss strategies to address these issues, including eco-friendly etching techniques and novel material combinations, and propose future research directions. This review highlights that SiC-based tandem systems achieve STH efficiencies up to 6.3 % and stability exceeding 100 days, with DFT modeling suggesting potential beyond 10 %