We, herein, report the synthesis of the first photocatalyst, tetragonal In2S3 nanoparticles, to display broad-spectrum photocatalytic properties under ultraviolet (UV), visible, and near-infrared irradiation from a simple hydrothermal method. The as-synthesized In2S3 nanoparticles have irregular morphology and possess a primary particle size of 5-20nm with high photo-degradation abilities under UV (96.2% within 30 min), visible light (95.4% within 3 h) and near-infrared light (67.2% within 3 h), a phenomenon extremely rare in character with respect to a broad class of photocatalysts that have a single crystalline phase. This current work in broadband spectrum photocatalysis affords a new paradigm for the full utilization of solar light. (C) 2015 Elsevier B.V. All rights reserved.