Deprotonation promoted high oxygen evolution activity of plasma functionalized carbon cloth.

• Plasma functionalized carbon cloth is prepared. • Oxygen containing functional groups formed on the carbon cloth surface. • The functionalized carbon cloth exhibits a great enhancement of OER activity. • Acceleration of surficial proton transfer probably enhances the OER activity. This paper reports a simple and facile method to prepare surface functionalized commercial carbon cloth via a plasma treatment and its application in electrocatalytic oxygen evolution reaction (OER). It is observed that abundant oxygen containing functional groups formed on the surface of the treated carbon cloth. The functionalized carbon cloth (FCC) exhibits a remarkable of OER activity. Specifically, it can drive a current density of 10 mA cm−2 at a fairly low overpotential of 360 mV and a correspondent small Tafel slope of 66.7 mV dec−1. More unexpectedly, it was found that the OER activity of FCC follows the non-concerted proton-coupled electron transfer mechanism. A possible explanation was proposed that the surface carboxyl groups improve the proton-transfer kinetics, accelerating the deprotonation from OOH to OO* during the OER process. [ABSTRACT FROM AUTHOR]