Zhang Xu, Cai Min, Cui Naxin, Chen Guifa, Zou Guoyan, Zhou Li
Institute of Eco-Environmental and Plant Protection, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.
Shanghai Engineering Research Center of Low-Carbon Agriculture, Shanghai 201403, China.
Nanomaterials (Basel). 2021 Oct 9;11(10):2648. doi: 10.3390/nano11102648.
A series of black TiO with and without the addition of urea were successfully prepared using a simple one-step synthetic method by calcination under different atmospheres (vacuum, He, or N). The physicochemical, optical, and light-induced charge transfer properties of the as-prepared samples were characterized by various techniques. It was found that a vacuum atmosphere was more beneficial for the formation of oxygen vacancies (OVs) than the inert gases (He and N) and the addition of urea-inhibited OVs formation. The samples annealed in the vacuum condition exhibited better visible-light adsorption abilities, narrower bandgaps, higher photo-induced charge separation efficiency, and lower recombination rates. Hydroxyl radicals (·OH) were the dominant oxidative species in the samples annealed under a vacuum. Finally, the samples annealed under vacuum conditions displayed higher photocatalytic activity for methylene blue (MB) degradation than the samples annealed under He or N. Based on the above, this study provides new insights into the effects of annealing atmospheres and urea addition on the properties of black TiO.
通过在不同气氛（真空、氦气或氮气）下煅烧，采用简单的一步合成法成功制备了一系列添加和未添加尿素的黑色TiO。通过各种技术对所制备样品的物理化学、光学和光诱导电荷转移性质进行了表征。结果发现，与惰性气体（氦气和氮气）相比，真空气氛更有利于氧空位（OVs）的形成，而尿素的添加抑制了OVs的形成。在真空条件下退火的样品表现出更好的可见光吸附能力、更窄的带隙、更高的光诱导电荷分离效率和更低的复合率。羟基自由基（·OH）是在真空下退火的样品中的主要氧化物种。最后，真空条件下退火的样品对亚甲基蓝（MB）降解的光催化活性高于在氦气或氮气下退火的样品。基于以上研究，本研究为退火气氛和尿素添加对黑色TiO性能的影响提供了新的见解。
