In this study,the Ag/AgCl/WO3 plasmonic Z-scheme photocatalysts with different contents of Ag/AgCl nanoparticles (NPs) were prepared through a facile ultrasonic precipitation method in geothermal water,wherein the geothermal water served as the chlorine source.Then the photocatalytic activity was investigated by degradation of 4-Aminobenzoic acid (4-ABA) under visible-light irradiation.It was found that the as-prepared 50 wt% Ag/AgCl/WO3 photocatalyst showed the highest photocatalytic efficiency with 25.12 and 3.53 times higher than those of pure WO3 and Ag/AgCl,respectively.The active species trapping experiments indicated that h+ and ·O2 were key factors in 4-ABA photodegradation process.The possible plasmonic Z-scheme photocatalytic mechanism of photocatalytic reaction for 4-ABA degradation was proposed based on systematical characterizations.We hope this paper could give new ideas for further exploiting geothermal energy to design and fabricate highly efficient visible-light-driven photocatalysts for environmental remediation.