Heterogeneous ZnO SrTiO3 nanocomposites were synthesized via a facile hydrothermal method. The highest H-2 production rate, 1317.44 mu mol g(-1), within 5 h under solar-light irradiation was achieved for the Zn/Sr ratio of 9:1 of the ZnO SrTiO3. More interestingly though the ZnO SrTiO3 is a semiconducting system, it could be used as an electrolyte in the low temperature solid oxide fuel cell without electronic conducting short circuiting problem. This device displayed an open circuit voltage of 1.14 V and reached the maximum power density of 564 mW cm(-2) at 550 degrees C. These results are attributed to the enhanced separation of the charge-hole pairs by the heterogeneous structure of ZnO SrTiO3 nano composites, which possess obvious both heterogeneously ionic and semiconduction. This new discovery indicates a good promising candidate for both solar and hydrogen energy conversions. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.