Fabrication of Carbon-Coated Silicon Nanowires for Photoelectrochemical Water Splitting

Carbon was deposited onto silicon nanowires (SiNWs) via pyrolysis to form a high-performance Carbon/SiNWs photocathode. Compared with pristine SiNWs, the carbon-modified photocathode exhibited substantially enhanced photoelectrochemical performance, achieving a photocurrent density of-13.45 mA·cm −2 at 0 V vs RHE and an onset potential of 0.597 V vs RHE, indicating a 0.413 V positive shift relative to unmodified SiNWs. Electrochemical impedance spectroscopy indicated a reduction in charge transfer resistance (R ct) from 1005 Ω (pristine) to 91 Ω (carbon-coated). These results demonstrate that carbon deposition is an effective strategy to enhance the photoelectrochemical performance of silicon-based photocathodes, offering direct relevance for solar energy conversion and water-splitting applications.