Mesoporous silicon carbide nanofibers with in situ embedded carbon for co-catalyst free photocatalytic hydrogen production

Silicon carbide (SiC) has been considered a promising metal-free photocatalyst due to its unique photoelectrical properties and thermal/chemical stability. However, its performance suffers from the fast recombination of charge carriers. Herein, we report mesoporous SiC nanofibers with in situ embedded graphitic carbon (SiC NFs-Cx) synthesized via a one-step carbothermal reduction between electrospun carbon nanofibers and Si powders. In the absence of a noble metal co-catalyst, the hydrogen evolution efficiency of SiC NFs-Cx is significantly improved under both simulated solar light (180.2 μmol·g^–1·h^–1) and visible light irradiation (31.0 μmol·g^–1·h^–1) in high-pH solution. The efficient simultaneous separation of charge carriers plays a critical role in the high photocatalytic activity. The embedded carbon can swiftly transfer the photogenerated electrons and improve light absorption, whereas the additional hydroxyl anions (OH^–) in highpH solution can accelerate the trapping of holes. Our results demonstrate that the production of SiC NFs-Cx, which contains exclusively earth-abundant elements, scaled up, and is environmentally friendly, has great potential for practical applications. This work may provide a new pathway for designing stable, lowcost, high efficiency, and co-catalyst-free photocatalysts.