We describe stable intercalation compounds of the composition xN2·WO3 (x = 0.034−0.039), formed by trapping N2 in WO3. The incorporation of N2 significantly reduced the absorption threshold of WO3; notably, 0.039N2·WO3 anodes exhibited photocurrent under illumination at wavelengths ≤640 nm with a faradaic efficiency for O2 evolution in 1.0 M HClO4(aq) of nearly unity. Spectroscopic and computational results indicated that deformation of the WO3 host lattice, as well as weak electronic interactions between trapped N2 and the WO3 matrix, contributed to the observed red shift in optical absorption. Noble-gas-intercalated WO3 materials similar to xN2·WO3 are predicted to function as photoanodes that are responsive to visible light.
Qixi Mi finds New WO3 Form
A new paper in J. Am. Chem. Soc. describes a Thermally Stable N2‐Intercalated WO3 Photoanodes for Water Oxidation written by Qixi Mi, Yuan Ping, Yan Li, Bingfei Cao, Bruce S. Brunschwig, Peter G. Khalifah, Giulia A. Galli, Harry B. Gray, and Nathan S. Lewis.