Simple and low-cost colorimetric method for quantification of surface oxygen vacancy in zinc oxide

Zinc oxide (ZnO) nanoparticles with surface oxygen vacancy (O V ) was found to catalyze the colorimetric reaction of 3,3′,5,5′-tetramethylbenzidine (TMB)−H 2 O 2 , and the absorbance of this TMB−H 2 O 2 –ZnO system was strongly dependent the O V concentration on surface of ZnO. By taking advantage of this phenomenon, one colorimetric method was proposed for quantifying surface O V in ZnO. The surface O V amount obtained through this colorimetric method matched well with that obtained through X-ray photoelectron spectroscopy (XPS). This colorimetric method doesn't need any advanced instruments, and can be completed in any an ordinary laboratory. This colorimetric method for detecting surface O V amount was simple, rapid (about 15 min) and low-cost.