Synthesis of nitrogen and sulfur-nitrogen co-doped carbon-based oxygen reduction reaction catalyst from rice straw and reeling waste of muga silk (Anthraea assamensis)

Abstract

Nitrogen-doped (N-G) and sulfur-nitrogen co-doped (SN-G) carbon-based electrocatalysts from two different biomass waste are successfully synthesized, and their ORR catalytic activity is also examined. In this research work, a simple preparation route for the synthesis of N-G catalyst from rice straw as a carbon source and urea as a nitrogen source is developed. Another facile route is developed for the synthesis of SN-G catalyst from reeling waste of muga silk (Anthraea assamensis) and thiourea (N and S source). Synthesized catalysts are characterized thoroughly for composition and microstructure details using XRD, Raman spectroscopy, FT-IR, FESEM, XPS, and BET surface area analyzer. The XPS analyses of the synthesized N-G and SN-G catalysts revealed that the nitrogen contents in both the catalysts are 0.85 and 14.85 At. %, respectively. Simultaneously, the sulfur content in the SN-G catalyst is found to be 2.94 At. %. Cyclic voltammetry is used for the evaluation of the catalytic activity of the catalysts towards ORR reaction in oxygen saturated 0.1 M KOH solution.