A yolk–shell Bi@void@SnO2 photocatalyst with enhanced tetracycline degradation. - Wu, Xiang-Feng; Wang, Yi-Jin; Song, Lian-Jun; Su, Jun-Zhang; Zhang, Jia-Rui; Jia, Yun-Ning; Shang, Jia-Lu; Nian, Xiao-Wei; Zhang, Chen-Yu; Sun, Xiu-Guo (Journal of Materials Science: Materials in Electronics, 2019)