Platinum Cluster Decoration on Hollow Carbon Spheres for High-Efficiency Hydrogen Evolution Reaction.

Currently, platinum (Pt)/carbon support composite materials have tremendous application prospects in the hydrogen evolution reaction (HER). However, one of the primary challenges for boosting their performance is designing a substrate with the desired microstructure. Herein, the intact hollow carbon spheres (HCSs) were prepared via template method. Based on the morphology variation of the as-prepared HCSs- x , we conjectured that the polydopamine (PDA) core was generated first and then slowly grew into a complete overburden (SiO 2 @PDA). Afterward, Pt atomic clusters were anchored on the outer shells of HCSs-4 to construct composite electrocatalysts (Pt y /HCSs-4) by a chemical reduction method. Due to the low charge-transfer resistance, the HCSs have a large electrochemical surface area and provide a continuous electron transport pathway, boosting the atom utilization efficiency during hydrogen production and release. The synthesized Pt 2.5 /HCSs-4 electrocatalysts exhibit excellent HER activity in acidic media, which can be ascribed to the compositional modulation and delicate structural design. Specifically, when the overpotential is 10 A g -1 , the overpotential can achieve 92 mV. This work opens a new route to fabricate Pt-based electrocatalysts and brings a new understanding of the formation mechanism of HCSs.