Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science of Shanxi Normal University, Taiyuan 030032, China.
Molecules. 2023 Jun 13;28(12):4739. doi: 10.3390/molecules28124739.
Surface oxygen vacancy (OV) plays a pivotal role in the activation of molecular oxygen and separation of electrons and holes in photocatalysis. Herein, carbonaceous materials-modified MoO nanospheres with abundant surface OVs (MoO/C-OV) were successfully synthesized via glucose hydrothermal processes. In situ introduction of carbonaceous materials triggered a reconstruction of the MoO surface, which introduced abundant surface OVs on the MoO/C composites. The surface oxygen vacancies on the obtained MoO/C-OV were confirmed via electron spin resonance spectroscopy (ESR) and X-ray photoelectron spectroscopy (XPS). The surface OVs and carbonaceous materials boosted the activation of molecular oxygen to singlet oxygen (O) and superoxide anion radical (•O) in selectively photocatalytic oxidation of benzylamine to imine. The conversion of benzylamine was 10 times that of pristine MoO nanospheres with a high selectivity under visible light irradiation at 1 atm air pressure. These results open an avenue to modify Mo-based materials for visible light-driven photocatalysis.
表面氧空位 (OV) 在光催化中对分子氧的活化和电子和空穴的分离起着关键作用。本文通过葡萄糖水热过程成功合成了具有丰富表面 OV 的含碳材料修饰的 MoO 纳米球 (MoO/C-OV)。原位引入的含碳材料引发了 MoO 表面的重构，在 MoO/C 复合材料上引入了丰富的表面 OV。通过电子自旋共振光谱 (ESR) 和 X 射线光电子能谱 (XPS) 证实了所得 MoO/C-OV 上的表面氧空位。表面 OV 和含碳材料促进了分子氧向单线态氧 (O) 和超氧阴离子自由基 (•O) 的活化，从而在苄胺选择性光催化氧化为亚胺中表现出优异的性能。在 1 大气压空气下可见光照射下，苄胺的转化率是原始 MoO 纳米球的 10 倍，具有很高的选择性。这些结果为修饰 Mo 基材料用于可见光驱动的光催化开辟了一条途径。
