Ultrathin carbon layer stabilized metal catalysts towards oxygen reduction

Abstract

A novel ultrathin carbon layer (UTCL) stabilized Pt catalyst (Pt-UTCL/C) with an open framework is synthesized to significantly enhance the stability of the catalyst in proton exchange membrane fuel cells. Herein, a cheap and widely available polymer, soluble starch (SS), as a precursor, is employed to wrap Pt nanoparticles (NPs) and is then carbonized into a UTCL with a thickness of few molecular-layers (0.58 nm on average) at a mild temperature. Significantly, it possesses extremely high stabilities of both electrochemical surface area and ORR compared to the commercial Pt/C catalyst even after 10 000 potential cycles. Such excellent stability can be ascribed to the anchoring effect of the UTCL towards Pt NPs to the inhibited migration, agglomeration and detachment of Pt NPs from the supports as well as to the possibly mitigated dissolution-growth process of Pt NPs in light of the UTCL.