Exploitation of novel photocatalysts for highly efficient degradation of organic dyes and reduction of hexavalent chromium is of significance to reduce environmental pollution. Herein, a novel three-dimensional flower-like Bi2S3 nanocrystals composed of two-dimensional Bi2S3 nanosheets were prepared by one-pot hydrothermal method with polyvinyl pyrrolidone (M-w = 1300000) as a capping agent. The experimental results show that polyvinyl pyrrolidone has evident enhanced effect on the photocatalytic performance of Bi2S3, and the polyvinyl pyrrolidone modified three-dimensional Bi2S3 (Bi2S3-1) displays extraordinary catalytic activity for photodegradation of rhodamine B and photoreduction of Cr(VI) under visible light. The rates of photodegradating rhodamine B and photoreducing Cr(VI) with Bi2S3-1 can reach 93.9% in 30 min (k = 0.07675 min (1)) and 95.2% in 5 min (k = 0.47351 min (1)), respectively. The photocatalytic performance of polyvinyl pyrrolidone modified three-dimensional Bi2S3 is much better than those of previously reported bismuth-based nanostructures. This work provides a new insight into the development of inorganic photocatalysts for both degradation of organic dyes and reduction of heavy metal ions. (C) 2020 Elsevier Inc. All rights reserved.