RCRE: Upcycling Wool Carpets into Electrodes for Wearable Electrolysers

Abstract

Recycled wool felt has been successfully converted into electrocatalysts for water splitting, through reduction- carbonization-activation treatments. By taking advantages of natural disulphide bonds in wool keratin, we selectively fixed the cobalt atoms in the wool fibers with a high loading of 4.76 wt% after carbonization. The as obtained cobalt sulphide supported by N,P-doped carbons further contributed to the water splitting reaction. The Fix-Co catalysts possessed a favourable HER (n10= 90 mV)/OER (n10= 295 mV) activity in 1.0M KOH. The as-fabricated electrolyser exhibited a low cell voltage of 1.62 V at 10 mA cm-2 with low current decay (~ 4.7%) after 15 hrs operation. Compared with that of physically adsorbed cobalt ions (Ads-Co), the superior electrochemical activity of Fix-Co originated from the well-constructed pore system, synergistic effect between Co9S8 and phosphorus doping, and good conductivity of carbon frameworks.
Apart from the electrochemical measurement, a flexible and wearable device based on Fix-Co catalysts has been designed and constructed. By adopting the concept of hydrogel spacer and moisture capturing salts, the wearable device can effectively adsorb humid, and convert moisture to hydrogen gas with a stable working current under a 3.0 V input. This work demonstrated a strategy to utilize the recycled wool keratin as precursors for the synthesis of transition-metal electrocatalysts and personalized device.

Biography

Professor Bin FEI is a Master program leader from the School of Fashion & Textiles, The Hong Kong Polytechnic University. He obtained BSc from the University of Science & Technology of China, and PhD from the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. His current research focuses Protective Textiles and Functional Fibers, Smart Polymers & Sustainable Composites, as well as Energy Materials & Wearable Electronics. So far, he has successfully supervised over 10 PhD students and 30 postdoctoral fellows, and completed projects with funding over HK$30 million. His materials group has produced over 150 SCI publications with H-index of 50. He is ranked as Top 2% of Scientists in the World.