Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
Anal Chem. 2022 Jun 21;94(24):8642-8650. doi: 10.1021/acs.analchem.2c00359. Epub 2022 Jun 9.
Defect engineering is an effective strategy to improve the catalytic activity of metal oxides, and quantitative characterization of surface defects is thus vital to the understanding and application of metal oxide catalysts. Herein, we found that ZnO nanoparticles with oxygen vacancy could trigger the luminol-HO system to emit a strong chemiluminescence (CL), and the CL intensity was strongly dependent on the oxygen vacancy of the ZnO nanoparticles. The mechanism of this CL reaction was discussed by means of the electron-spin resonance spectrum, X-ray photoelectron spectrum (XPS), and CL spectrum. The oxygen vacancy-dependent CL was attributed to the ability of the oxygen vacancy to readily adsorb and further dissociate HO into active OH radicals. Taking advantage of this oxygen vacancy-dependent CL, we presented one method for quantifying the oxygen defects in ZnO. Compared with the current evaluation techniques (XPS and Raman spectroscopy), this CL method is rapid, low-cost, and easy to operate. This work introduces the CL technique into the field of material structure-property evaluation, and provides a new approach for exploring the defect function in ZnO defect engineering.
缺陷工程是提高金属氧化物催化活性的有效策略，因此定量表征表面缺陷对于理解和应用金属氧化物催化剂至关重要。本文发现，具有氧空位的 ZnO 纳米粒子可以触发鲁米诺-HO 体系发出强化学发光（CL），并且 CL 强度强烈依赖于 ZnO 纳米粒子的氧空位。通过电子自旋共振谱、X 射线光电子能谱（XPS）和 CL 谱对该 CL 反应的机理进行了讨论。氧空位依赖性 CL 归因于氧空位易于吸附并进一步将 HO 解离成活性 OH 自由基的能力。利用这种氧空位依赖性 CL，我们提出了一种定量测定 ZnO 中氧缺陷的方法。与当前的评估技术（XPS 和拉曼光谱）相比，该 CL 方法快速、低成本且易于操作。这项工作将 CL 技术引入材料结构-性能评估领域，为探索 ZnO 缺陷工程中的缺陷功能提供了一种新方法。
