Visible light driven photosplitting of water using one dimensional Mg doped ZnO nanorod arrays Pooja Sahoo a , Akash Sharma a , Subash Padhan b , R. Thangavel a,* a Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, Jharkhand, India b Department of Chemistry, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, Jharkhand, India highlights graphical abstract  We introduced Mg doped ZnO nanorods as photoanodes for solar water splitting.  A superior photoelectrochemical performance and better electron lifetime was observed.  10% Mg doped ZnO photoanode exhibited long term photostability in natural seawater. article info Article history: Received 17 March 2020 Received in revised form 12 June 2020 Accepted 18 June 2020 Available online xxx Keywords: Mg doped ZnO Nanorods Water splitting Photoconversion efficiency abstract In the present work, we have introduced Mg doped ZnO nanorods based photoanodes for photoelectrochemical water splitting applications. Vertically aligned Mg doped ZnO nanorods were fabricated by sol-gel and hydrothermal technique. The as-prepared nano- rod samples exhibited hexagonal wurtzite structure as confirmed from XRD measure- ments. We achieved a photocurrent density of 0.35 mA/cm 2 at 1.5 V vs. Ag/AgCl for 10% Mg doped ZnO photoanode which is 9 times higher than that of undoped ZnO nanorods (0.03 mA/cm 2 ). Incorporation of Mg resulted in faster charge transport and longer life time of electrons with reduced recombination rate. Mg dopant tuned the optical band gap of ZnO and increased the carrier concentration boosting the PEC performance of the photo- anodes. Since seawater is one of the most abundant natural resource on earth, we further carried out seawater splitting of 10MgZ under visible light illumination which indicated its high photostability in natural seawater for 5 h of continuous illumination. © 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. * Corresponding author. E-mail address: rthangavel@iitism.ac.in (R. Thangavel). Available online at www.sciencedirect.com ScienceDirect journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy xxx (xxxx) xxx https://doi.org/10.1016/j.ijhydene.2020.06.173 0360-3199/© 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. Please cite this article as: Sahoo P et al., Visible light driven photosplitting of water using one dimensional Mg doped ZnO nanorod arrays, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2020.06.173