Size effects of platinum particles@CNT on HER and ORR performance

Abstract

Platinum (Pt) is an efficient catalyst for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR), but the debate of the relevance between the Pt particle size and its electrocatalytic activity still exist. The strong metal-support interaction (SMSI) between the metal and carrier causes the charge transfer and mass transport from the support to the metal. Herein, Pt species (0.5 wt.%) with various particle sizes supported on carbon nanotubes (CNTs) have been synthesized by a photo-reduction method. Thẽ 1.5 nm-sized Pt catalyst shows much higher HER performance than the counterparts in all pH solutions, and the mass activity of it is even 23-36 times that of Pt/C. While for ORR, the~3 nm-sized Pt catalyst exhibits the optimal performance, and the mass activity is 3 times and even 16 times that of Pt/C in acidic and alkaline media, respectively. The high HER and ORR performances of the~1.5 nm-and~3 nm-sized Pt catalysts benefit from the SMSI between Pt and the CNTs matrix and the higher ratio of face sites to edge sites, which is meaningful for the design of efficient electrocatalysts for renewable energy application.

A fundamental comprehension and recent progress in advanced Pt‐based ORR nanocatalysts

“…29,[140][141][142] In addition, the high mass transport and electronic excursion and atomic contraction effect rooting from the fold surface are all beneficial for enhanced ORR performance. [143][144][145] Furthermore, collaborative adoptions of these abovementioned will lead to exponential growth toward ORR performance. For example, Xia and coworkers reported hollow PtNi nanobranched nanostructure 94 showed a 3.52 A/mg Pt of mass activity, which is 14 times higher as compared with a commercial platinum on carbon (Pt/C) catalyst.…”

“…(iii) Constructing the hollow nanostructure, the subnanometer‐thick walls of hollow nanostructured Pt‐based catalysts not only reduces the usage of Pt weigh but also increase the utilization of Pt 29,140–142 . In addition, the high mass transport and electronic excursion and atomic contraction effect rooting from the fold surface are all beneficial for enhanced ORR performance 143–145 . Furthermore, collaborative adoptions of these abovementioned will lead to exponential growth toward ORR performance.…”

Anchoring Sub‐Nanometer Pt Clusters on Crumpled Paper‐Like MXene Enables High Hydrogen Evolution Mass Activity

“…Placing Pt species on appropriate substrates would be a promising tactic to stabilize Pt sub‐nanometer clusters. [ 4 ]…”

“…Placing Pt species on appropriate substrates would be a promising tactic to stabilize Pt sub-nanometer clusters. [4] MXenes, first reported in 2011, are a new type of 2D transition metal carbides and nitrides. Benefited from its unique physiochemical features, such as high conductivity, affluent surface termination groups, outstanding hydrophilicity, and synthetic diversity, MXene has attracted great attention in secondary batteries, [5] supercapacitors, [6] electromagnetic shielding, [7] sensors, [8] and photo/ electrocatalysts.…”

Ultra-Thin SnS2-Pt Nanocatalyst for Efficient Hydrogen Evolution Reaction

“…Electrocatalysts for hydrogen evolution from water have been extensively studied for their advantages, having high purity and use in environmentally friendly products [5,6]. Now, Pt [7] and Pt-based catalysts have been considered as the most effective HER electrocatalysts reported in the literature [8]. However, the poor electrochemical stability, high production costs [9] and the raw material scarcity limits their mass production to meet the industrial demand.…”