OICC Press Journal of Nanostructure in Chemistry 2193-8865 11 1 (March 2021) 2020 10 10 Rapid photodecolorization of methyl orange and rhodamine B using zinc oxide nanoparticles mediated by pullulan at different calcination conditions 10.1007/s40097-020-00358-6 EN Eleen Dayana Mohamed Isa Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Kuala Lumpur, 54100, MY Kamyar Shameli Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Kuala Lumpur, 54100, MY Nurfatehah Wahyuny Che Jusoh Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Kuala Lumpur, 54100, MY Advanced Materials Research Group, Center of Hydrogen Energy, Universiti Teknologi Malaysia, Kuala Lumpur, 54100, MY Roshasnorlyza Hazan Malaysian Nuclear Agency, Kajang, Selangor, 43000, MY Journal Article 2020 10 10 Abstract Water is one of the humanity’s major resources, but it is actually at risk due to growth and urbanization. Water reclamation and reuse was introduced as one of the solutions. However, the presence of organic pollutants, such as dyes, in the reclaim water can cause adverse effect to human. The dyes can be removed through photocatalysis process where semiconductor materials such as zinc oxide (ZnO) is used as the catalyst. In this research, several zinc oxide nanoparticles (ZnO NPs) were developed with pullulan as the capping agent through green synthesis. The impact of calcination conditions on the properties of synthesized ZnO NPs was explored. All the synthesized samples were subjected to photocatalytic degradation of two dyes, methyl orange (MO) and rhodamine B (RhB). The results indicated that with the increment of calcination temperature, the average particles size increased from 28.86 to 127.69 nm and the surface area reduced from 30.7996 to 12.3757 m 2  g −1 . As the calcination time changed, substantial impact was observed where, as calcination time increased to 2 h, the average particles size and the surface area significantly increased and reduced, respectively. The best photocatalytic degradation of MO and RhB was observed using ZnO NPs produced at 400 °C and 1 h calcination conditions. Overall, ZnO NPs have a good prospect to be applied for removal of dyes in wastewater. Graphic abstract