Millisecond-timescale electrodeposition of platinum atom-doped molybdenum oxide as an efficient electrocatalyst for hydrogen evolution reaction

We present a straightforward method for one-pot electrodeposition of platinum atoms-doped molybdenum oxide(Pt·MoO_(3-x))films and show their superior electrocatalytic activity in the hydrogen evolution reaction(HER).A~15-nm-thick Pt·MoO_(3-x) film was prepared by one-pot electrodeposition at-0.8 V for 1 ms.Due to considerably different solute concentrations,the content of Pt atoms in the electrode-posited composite electrocatalyst is low.No Pt crystals or islands were observed on the flat Pt-MoO_(3-x) films,indicating that Pt atoms were homogeneously dispersed within the MoO_(3-x) thin film.The catalytic performance and physicochemical features of Pt·MoO_(3-x) as a HER electrocatalyst were characterized.The results showed that our Pt·MoO_(3-x) film exhibits 23-and 11-times higher current density than Pt and MoO_(3-x) electrodeposited individually under the same conditions,respectively.It was found that the dramatic enhancement in the HER performance was principally due to the abundant oxygen defects.The use of the developed one-pot electrodeposition and doping method can potentially be extended to various catalytically active metal oxides or hydroxides for enhanced performance in various energy storage and conversion applications.