CO2 assisted synthesis of silk fibroin driven robust N-doped carbon aerogels coupled with nickel–cobalt particles as highly active electrocatalysts for HER

• Published in: International journal of hydrogen energy Vol. 46; no. 41; pp. 21525 - 21533
• Main Authors: Sam, Daniel Kobina, Wang, Wenbo, Gong, Shanhe, Sam, Ebenezer Kobina, Lv, Xiaomeng, Wang, Jie, Liu, Jun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.06.2021
• Subjects: Biomass; Carbon aerogel; Electrocatalyst; Hydrogen evolution reaction; Silk fibroin; Hydrogen evolution reaction; Electrocatalyst; Silk fibroin; Biomass; Carbon aerogel
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2021.03.243

Hydrogen evolution reaction (HER), has been considered as an ideal alternative energy system to alleviate the global energy crisis. Unfortunately, the rational design of a cost-effective, highly active and stable electrocatalyst remains a tough challenge. In this work, a CO2 assisted synthesis of N- doped carbon aerogel derived from silk fibroin (SFCA) without any additives was used to anchor Nickel–Cobalt (NiCo) nanoparticles as an HER electrocatalyst in basic medium (1 M KOH). The obtained SFCA-NiCo electrocatalyst demonstrated outstanding electrochemical performance having an onset potential of 52 mV and a low overpotential of 179 mV at current density of 10 mA cm−2, whilst exhibiting long term stability when tested for 24 h. The outstanding electrocatalytic performance marks SFCA-NiCo as a favourable electrocatalyst for HER and the synthesis strategy paves way for constructing novel catalysts even for other areas. •Robust N-doped carbon aerogel was synthesized from silk cocoon with the aid of CO2.•The aerogel anchored with highly dispersed NiCo alloy worked as HER electrocatalyst.•The electrocatalyst showed low overpotential and low Tafel slope in basic medium.•The intrinsic property of carbon aerogel helped to enhance the electron and mass transport.•The aggregation/accumulation of NiCo nanoparticles was prevented with improved activity and stability.