XPS Determination of the Surface Composition of Vanadyl Pyrophosphate Catalysts
The surface P/V ratios of vanadyl pyrophosphates ((VO)2P2O7), which were selective catalysts for the oxidation of butane to maleic anhydride, were determined to be close to that of the bulk (P/V = 1) by XPS using V–P–O glasses as standard materials.