Water splitting is one of renewable and environmentally-friendly energy sources.

Understanding the reactions between water molecules and isolated metal atoms/clusters, which can boost catalytic performance, is helpful to reveal the microscopic mechanisms of water splitting at molecular level. However, the experimental investigation of the reactions between water molecules and neutral metals is challenging due to the neutral clusters, lack of charges, are hard to be detected.

Recently, a research team led by Prof. JIANG Ling and Dr. LI Gang from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences studied the reactions of water with neutral vanadium (V) dimer by using a size-specific infrared-vacuum ultraviolet spectroscopy, and realized water splitting.

This study was published in The Journal of Physical Chemistry Letters on April 17.

The researchers measured infrared spectra for the neutral V2O3H4 and V2O4H6 complex in the 2800-4100 cm-1 spectral region by recently-developed infrared spectroscopy using a tunable vacuum ultraviolet free electron laser (VUV-FEL).

They found that V2O3H4 and V2O4H6 had unexpected V2(μ2-OH)(μ2-H)(η1-OH)2 and V2(μ2-OH)2(η1-H)2(η1-OH)2 structures, indicating the exist of water splitting. Moreover, they indicated that the water splitting by V2 was both thermodynamically exothermic and kinetically facile in the gas phase.

"Our study provides new avenues toward systematic understanding of water splitting by a large variety of single-cluster catalysts," said Prof. JIANG.