Silicon-compatible carbon-based catalyst with high HER activity from rich silicon biomass

To solve the issue to high cost, high energy consumption and environmental crisis arising for noble/transition metal based catalysts in electrocatalytic water field, the carbon-based silicon microspheres with excellent electrocatalytic properties were prepared from waste biomass-rice husk (silicon-rich biomass) without metal additives via using self-construction method. The structures of nanoscale silica microspheres on the surface of the samples were controlled by the effect of Si-O-C bonds. The specific Si-O-C bonds derived from the amorphous silica of rice husk connected to the carbon matrix after carbonization process. The amorphous Si-O-C structure exhibits robust capabilities in water adsorption and decomposition during the electrocatalytic process, thereby accelerating the rate of electrocatalytic hydrogen evolution. The obtained Silicon-compatible carbon-based material exhibited excellent electrocatalytic hydrogen precipitation performance with an overpotential of 150 mV for HER and a Tafel slope of 35.93 mV dec−1 at a current density of 10 mA cm−2, respectively, as well as high stability. The results demonstrate that the biomass-based silicon-carbon materials are a promising HER catalyst, and this study broadens the potential application of biomass waste in electrocatalytic water splitting.