Ferroelectric photovoltaic is a new and important physical effect discovered in the study of the optoelectronic properties of ferroelectric materials in the 1970s. Because of the fundamental difference between the photovoltaic effect of conventional pn junction solar cells, this phenomenon is often It is called abnormal photovoltaic effect or bulk photovoltaic effect. In recent years, with the continuous concern of human society on energy and environmental issues, research on ferroelectric photovoltaic effect continues to heat up. At present, there are many physical mechanisms for ferroelectric photovoltaic effect. The model proposes that although there is still controversy between them, it is generally accepted that the existence of this effect is closely related to the polarity of the material.
Recently, Yi Zhiguo, a key laboratory for functional nanostructure design and assembly at the Institute of Research on the Structure of Matter, Institute of Material Structure, Chinese Academy of Sciences, discovered a bismuth vanadate material with a centrally symmetric structure during the cross-scientific research of ferroelectric physics and photocatalytic chemistry. It has a large abnormal photovoltaic effect. In the process of microstructural characterization in cooperation with the Li Yongxiang team of the Shanghai Institute of Ceramics, Chinese Academy of Sciences, it is further found that there is a large local strain fluctuation inside the bismuth vanadate material. After in-depth systematic research, reveal The anomalous photovoltaic effect originates from the local symmetry breaking mechanism induced by strain fluctuation. Moreover, the anomalous photovoltaic effect can be modulated by strain regulation. This work not only subverts the traditional understanding that ferroelectric photovoltaic effect exists only in polar compounds. Moreover, it provides new possibilities for the application of bismuth vanadate materials. Relevant results have been published in Advanced Materials, Dr. Liu Xitao, Ph.D., Fujian Institute of Physical Education and Dr. Zhang Faqiang, Shanghai Institute of Silicate, the first author of the thesis. During the review process, it was highly praised by journal editors and reviewers. Progress in the field of photovoltaic iconic ferroelectric.
The work was supported by the National Natural Science Foundation of China, the Frontier Science Key Project of the Chinese Academy of Sciences, and the Key Research and Development Program of the Ministry of Science and Technology. In the course of the experimental advancement, Zeng Huarong, a researcher at the Shanghai Institute of Silicate, and Liu Wei, a professor at the Australian National University, were also supported.
