Stepwise Reduction and In Situ Loading of Core‐Shelled Pt@Cu Nanocrystals on TiO₂–NTs for Highly Active Hydrogen Evolution

Abstract

A flexible and mild fabricating protocol, i.e., stepwise reduction and in situ loading route, is proposed to modulate ordered growing and dispersive depositing of Pt@Cu bimetal layered nanostructure on titanium dioxide nanotubes (TiO2‐NTs) via reasonably regulating addition sequence and dosage for the reactants and additives. Comprehensive characterizations demonstrate that most of the Cu core‐Pt shell nanocrystals with a mean size of 10 nm evenly disperse on the surface of TiO2‐NTs, and a small number of nanocrystals permeate into the nanotubes. In comparison to TiO2‐NTs, the specific surface area declines after loading bimetals, with the pore size distribution shifting from micropores to mesopores. The catalytic activity of the Pt@Cu(x)/TiO2 for hydrolytic hydrogen evolution presents an increasing tendency as the bimetal loadings rise, each surpassing that of the bare bimetal nanocrystals. The H2 generating rate gradually rises with temperature increment. The AB hydrolysis catalyzed by Pt@Cu(9%)/TiO2 at the given temperatures (293–313 K) is affirmed as a first‐order reaction, with apparent activation energy of 28.43 kJ mol−1 and TOF value of 107.27 min−1. The catalyst Pt@Cu(9%)/TiO2 unfolds exceptionally high stability, remaining 91% initial catalytic activity after five cycling use.

Hydrogen production from chemical hydrogen storage materials over copper‐based catalysts

“…Compared to monometallic catalysts, bimetallic catalysts exhibit more satisfactory catalytic performance both in terms of the activity and stability, which is due to the synergistic effects including the geometrical changes and electronic transfer between Cu and other transition metals, which can effectively suppress the aggregation of Cu NPs and enhance its catalytic activity. Up to date, a series of Cu-based noble and non-noble bimetallic catalysts such as CuRu, [192][193][194] CuPd, 165,[195][196][197] CuPt, [198][199][200] CuRh, 201 CuCo, [202][203][204][205][206][207][208][209][210][211][212][213][214][215][216] CuFe, 217 and CuNi [218][219][220][221] have been tested in the hydrolysis of AB. 3.2.1 | CuM (M: Noble metal) bimetallic catalysts Titanium dioxide (TiO 2 ) with wide sources, high stability, and diverse structures has attracted the attention of researchers.…”

“…Compared to monometallic catalysts, bimetallic catalysts exhibit more satisfactory catalytic performance both in terms of the activity and stability, which is due to the synergistic effects including the geometrical changes and electronic transfer between Cu and other transition metals, which can effectively suppress the aggregation of Cu NPs and enhance its catalytic activity. Up to date, a series of Cu‐based noble and non‐noble bimetallic catalysts such as CuRu, 192–194 CuPd, 165,195–197 CuPt, 198–200 CuRh, 201 CuCo, 202–216 CuFe, 217 and CuNi 218–221 have been tested in the hydrolysis of AB.…”