In this work, we have successfully synthesized silver nanoparticles (Ag-NPs) decorated binary PaNi/NBO nanocomposite by facile chemisorption route and demonstrated enhanced photoelectrochemical (PEC) water splitting activity. The ternary Ag/PaNi/NBO nanocomposite photoanode exhibits similar to 5 fold higher current density than pristine NaNbO3 nanofibers (NBO-NFs). The ternary Ag/PaNi/NBO photoanode exhibits a current density of 5.93 mA/cm(2) at 0.9 V with respect to Ag/AgCl, whereas the pristine NBO-NEs photoanode exhibits only 0.85 mA/cm(2) at 0.9 V. The improved performance is correlated to the high surface area, formation of the type-II heterojunction among PaNi and NBO-NEs and the introduction of the plasmonic behaviour of Ag-NPs as it expands the absorption of the visible part of the solar spectrum, which together decreases the recombination of charges with strong redox capability. Furthermore, the ternary Ag/PaNi/NBO photoanode showed lower charge transfer resistance (R-ct) in the EIS measurements and improved incident photon to current efficiency (IPCE) of similar to 31.3% which is similar to 23% higher to the IPCE of bare NBO-NEs photoanode. Thus, these results suggest that the ternary Ag/PaNi/NBO nanocomposite is a promising material for PEC activity and wide practical applications. (C) 2020 Elsevier Ltd. All rights reserved.