Küspert Sven, Campbell Ian E, Zeng Zhiqiang, Balaghi S Esmael, Ortlieb Niklas, Thomann Ralf, Knäbbeler-Buß Markus, Allen Christopher S, Mohney Suzanne E, Fischer Anna
Institute of Inorganic and Analytical Chemistry (IAAC), University of Freiburg, Albertstraße 21, 79104, Freiburg, Germany.
Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Straße 21, 79104, Freiburg, Germany.
Small. 2024 Aug;20(34):e2311260. doi: 10.1002/smll.202311260. Epub 2024 Apr 18.
Vapor-based deposition techniques are emerging approaches for the design of carbon-supported metal powder electrocatalysts with tailored catalyst entities, sizes, and dispersions. Herein, a pulsed CVD (Pt-pCVD) approach is employed to deposit different Pt entities on mesoporous N-doped carbon (MPNC) nanospheres to design high-performance hydrogen evolution reaction (HER) electrocatalysts. The influence of consecutive precursor pulse number (50-250) and deposition temperature (225-300 °C) are investigated. The Pt-pCVD process results in highly dispersed ultrasmall Pt clusters (≈1 nm in size) and Pt single atoms, while under certain conditions few larger Pt nanoparticles are formed. The best MPNC-Pt-pCVD electrocatalyst prepared in this work (250 pulses, 250 °C) reveals a Pt HER mass activity of 22.2 ± 1.2 A mg at -50 mV versus the reversible hydrogen electrode (RHE), thereby outperforming a commercially available Pt/C electrocatalyst by 40% as a result of the increased Pt utilization. Remarkably, after optimization of the Pt electrode loading, an ultrahigh Pt mass activity of 56 ± 2 A mg at -50 mV versus RHE is found, which is among the highest Pt mass activities of Pt single atom and cluster-based electrocatalysts reported so far.
