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

Abstract

AbstractA 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.