1 Influence of Au plasmons and their synergistic effects with ZnO nanorods for photoelectrochemical water splitting applications Sayed Abdul Saboor, Vidhika Sharma, Ebrima L. Darboe, Vidya Doiphode, Ashvini Punde, Pratibha Shinde, Vijaya Jadkar, Yogesh Hase, Ashish Waghmare, Mohit Prasad* School of Energy Studies, Savitribai Phule Pune University, Pune 411 007 (India) Sandesh Jadkar* Department of Physics, Savitribai Phule Pune University, Pune 411 007 (India) *Corresponding authors E-mail: sandesh@physics.unipune.ac.in (Sandesh Jadkar) Tele/Fax: + 91 020 2569 2678 mohitprasad7@gmail.com (Mohit Prasad) Tele/Fax: + 91 020 2569 2678 ABSTRACT In this paper, Au plasmons and their synergistic effects with ZnO nanorods (ZNs) have been investigated for photoelectrochemical (PEC) water splitting application. Au plasmons and ZNs are deposited electrochemically. Au modified nanostructures have absorption in the visible region as plasmons enhance charge transfer and inhibit charge recombination. ZNs modified with Au (deposition duration 60 s) has a photo-current density of 660 μA cm -2 , at a bias of 1.0V/SCE. X-ray diffraction and scanning electron microscopy were used to study the structure and surface morphology of fabricated photoanodes. UV- Visible absorption and Photoluminescence spectroscopy were used for optical characterization. We have recorded current-voltage measurements and photo-conversion efficiency measurements to substantiate our observations of the synthesized photoanodes for prospective application in PEC splitting of water. We have also carried out Mott-Schottky, and electrochemical impedance spectroscopy analysis. The analysis reveals that Au modified ZNs based photoanodes are a better proposition than their bare counterparts for PEC water splitting application. KEYWORDS: Photo-current; Plasmons; Photoelectrochemical; Zinc oxide