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

Abstract

Abstract Preparing stable highly dispersed Pt based electrocatalyst is promising to reduce material expense of H2 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 H2 evolution in acidic electrolyte.

Keywords

• acidic electrolyte
• carbon nanotubes
• carbon quantum dots
• H2 evolution
• Pt atomic clusters