Invited article Advances in photocatalytic disinfection of bacteria: Development of photocatalysts and mechanisms Wanjun Wang 1, 3 , Guocheng Huang 3 , Jimmy C. Yu 1, 2, ⁎ , Po Keung Wong 3, ⁎ 1. Department of Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China 2. Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China 3. School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China ARTICLE INFO ABSTRACT Article history: Received 14 April 2015 Revised 28 May 2015 Accepted 28 May 2015 Available online 24 June 2015 Photocatalysis has attracted worldwide attention due to its potential in solar energy conversion. As a “green” advanced oxidation technology, it has been extensively used for water disinfection and wastewater treatment. This article provides a review of the recent progress in solar energy-induced photocatalytic disinfection of bacteria, focusing on the development of highly efficient photocatalysts and their underlying mechanisms in bacterial inactivation. The photocatalysts are classified into TiO 2 -based and non-TiO 2 -based systems, as TiO 2 is the most investigated photocatalyst. The synthesis methods, modification strategies, bacterial disinfec- tion activities and mechanisms of different types of photocatalysts are reviewed in detail. Emphasis is given to the modified TiO 2 , including noble metal deposition, non-metal doping, dye sensitization and composite TiO 2 , along with typical non-TiO 2 -based photocatalysts for bacterial disinfection, including metal oxides, sulfides, bismuth metallates, graphene-based photocatalysts, carbon nitride-based photocatalysts and natural photocatalysts. A simple and versatile methodology by using a partition system combined with scavenging study is introduced to study the photocatalytic disinfection mechanisms in different photocatalytic systems. This review summarizes the current state of the work on photocatalytic disinfection of bacteria, and is expected to offer useful insights for the future development in the field. © 2015 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. Keywords: Photocatalysis Bacterial disinfection TiO 2 Bismuth metallates Partition system Disinfection mechanism 1. Introduction The water crisis caused by lacking of clean freshwater has been one of the biggest challenges throughout the world. Problems with water are expected to grow worse in the coming decades, with water scarcity occurring globally (Montgomery and Elimelech, 2007). Every year, countless people are sickened from waterborne diseases, which have been transmitted through microorganisms such as viruses, bacteria and protozoa. Intestinal parasitic infections and diarrheal diseases caused by waterborne bacteria and enteric viruses have also become leading causes of malnutrition because they lead to poor digestion (Lima et al., 2000; Singh and Bengtsson, 2005; Shannon et al., 2008). In the coming decades, public health and environmental concerns would continue to drive efforts to decontaminate waters with more effective, lower-cost, and robust methods. Water disinfection is traditionally achieved by the addition of chlorine. However, numerous reports have confirmed the formation of potentially mutagenic and carcinogenic JOURNAL OF ENVIRONMENTAL SCIENCES 34 (2015) 232 – 247 ⁎ Corresponding authors. E-mails: jimyu@cuhk.edu.hk (Jimmy C. Yu), pkwong@cuhk.edu.hk (Po Keung Wong). http://dx.doi.org/10.1016/j.jes.2015.05.003 1001-0742/© 2015 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. Available online at www.sciencedirect.com ScienceDirect www.journals.elsevier.com/journal-of-environmental-sciences