Synthesis of nitrogen and sulfur bi-doped carbon obtained from spent sapelli wood sawdust and polyhydric alcohol with improved catalytic activity for hydrogen evolution reaction

Developing an efficient water electrolysis system is an important solution for on the development of highly active, cost-effective, and stable electrocatalysts. Carbon-based metal-free catalysts are one of the promising candidates for this purpose. Herein, we present a facile strategy to synthesize and characterize nitrogen and sulfur co-doped porous carbon (NS-PC) from spent sapelli wood sawdust and polyhydric alcohol (xylitol) for efficient hydrogen evolution reaction (HER) in alkaline electrolyte. The resultant NS-PC metal-free catalyst exhibits porous structure, high surface areas and enhanced HER performance with lowest Tafel slope of 68.1 mV dec-1. The enhanced performance is due to the high porosity of carbonaceous material and co-existence of active species (N in the forms of graphitic-N, pyridinic-N, pyrrolic-N, and S in the forms of C-S-C) induced by the maximum carbon-carbon bond polarization, charge re-distribution in the carbon matrices with a synergistically HER activity. In addition, this work provides a versatile and effective strategy for synthetizing excellent carbon-based metal free catalysts from the low cost biowaste for large-scale production of hydrogen through HER.