Stable Pt atomic clusters on carbon nanotubes grafted with carbon quantum dots as electrocatalyst for H₂ evolution in acidic electrolyte

Abstract

Preparing stable highly dispersed Pt based electrocatalyst is promising to reduce material expense of H 2 product via electrocatalytic water splitting. However, it is still a great challenge to obtain stable single atomic Pt catalysts which can be applied in acidic electrolyte. In the present work, we synthesized Pt atomic clusters on carbon quantum dots (CQDs) grafting multiwall carbon nanotube (CNT) (Pt content: 1 wt.%) catalysts and then loading the catalysts on carbon cloth (Pt content: 0.01 mg▪cm -2 ) for activity test. The overpotential of 29 mV versus RHE was obtained over 1%Pt/CQDs/CNT catalysts at the current density of 10 mA▪cm -2 , and the Tafel slope of 22 mV decade -1 was obtained, too. Especially, the catalysts showed significant stability in hydrogen evolution reactions (HER) in acidic solution, of which the overpotential was still smaller than that of 20%Pt/C after 10,000 CV cycles. CQDs provided coordinating sites for dispersing Pt atomic clusters and improved the H + concentration in adjacent area around the Pt clusters. This method provides a general strategy to design the highly efficient electrocatalysts with ultra-low precious metals for H 2 evolution in acidic electrolyte.

Experimental and Theoretical Advances on Single Atom and Atomic Cluster‐Decorated Low‐Dimensional Platforms towards Superior Electrocatalysts

“…The utilization of 1D-nanocarbon networks with unique microenvironments to precisely confine small metallic clusters is emerging as a desirable strategy to build ACEs. [118][119][120] Such confinement not only provides strong interactions between the reactants and the catalytic active species at 1D surfaces, but also leads to potential synergetic effects, enhancing the intimate contact between multiple active species and favoring the efficiency of many catalytic reactions, especially multistep catalytic processes such as NRR and CO 2 RR. As an ideal 1D platform, multiwall CNTs (MWCNTs) exhibit excellent electric conductivities, huge specific surface areas, and a lot of potential anchoring points as supports for tiny metallic clusters.…”