基底温度对三氧化钨薄膜光电化学性能的调控研究

Regulation of substrate temperature on photoelectrochemical properties of tungsten trioxide thin films

由于环境友好性、高的地球丰度和稳定的物理化学性质,三氧化钨在光电响应、光催化领域应用潜力巨大,受到了人们的广泛关注。薄膜形态的光催化材料能够避免粉体材料的团聚问题,并且在转移、回收再利用方面优势明显,因此制备用于光催化的三氧化钨薄膜是当前的研究前沿。本文通过磁控溅射在石英玻璃基底上沉积三氧化钨薄膜,研究了不同基底温度对薄膜结构和形貌的影响。采用X射线衍射、X射线光电子能谱、场发射扫描电镜、紫外可见吸收光谱、电化学工作站、光催化自组装平台对薄膜的成分形貌、光电化学性能、光催化活性进行表征。测试结果表明:基底温度为500℃时制备的单斜相三氧化钨薄膜具有较好的结晶性和更少缺陷,在500℃的基底温度下,新出现的(002)晶面取向的晶粒导致薄膜表面粗糙度和表面能增加,提升了光生电子空穴分离效率。光降解实验进一步证实此条件下制备的样品表现出最佳的光降解效率。可见,基底温度对磁控溅射制备的三氧化钨薄膜的光电化学性能有明显的调控作用。

Due to the characteristics of environmental friendliness,earth abundance,and stable physical and chemical properties of tungsten trioxide,it has great potential in the fields of photoelectric response and photocatalysis,and has attracted broad attention.Thin film photocatalytic materials can avoidthe agglomeration in powder materials,and have obvious advantages in transferring,recycling,and reusing.Thus,the preparation of tungsten trioxide thin films for photocatalysis is a hot research topic.In this study,tungsten trioxide thin films were deposited on glass substrates by magnetron sputtering,and the effects of different substrate temperatures on the structure and morphology of the thin films were investigated.X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),field emission scanning electron microscope(SEM),ultraviolet-visible(UV-Vis)absorption spectrum,electrochemical workstation,and photocatalytic self-assembly platform were used to characterize the composition morphology,photoelectrochemical properties,and photocatalytic activity of the films.Measurement results showed that monoclinic tungsten trioxide thin films prepared at substrate temperature of 500℃possessed better crystallinity and fewer defects.The appearance of(002)plane oriented grains at substrate temperature of 500℃led to the increase in surface roughness and surface energy,and improved the efficiency of photo-generated electron-hole separation.The photodegradation experiment further confirmed that the samples prepared under these conditions showed the best photodegradation efficiency.The research results in this paper indicatethat the substrate temperature has obvious control effect on the photoelectrochemical properties of tungsten trioxide thin films prepared by magnetron sputtering.