Abstract: WO₃-based composite nanostructures have been used as the promising materials for gas-sensing and photocatalytic applications. The performance of WO₃ composite nanostructures modified by noble metals can be greatly improved compared to individual WO₃ material. In this paper，the recent progress in the gas-sensing and photocatalytic properties of noble-metal-modified WO₃ composite nanostructures is reviewed. Effects of preparation methods and noble metal dopants on the gas-sensing properties to various gases，such as NO_x，H₂S，H₂ and etc.，have been discussed in detail. The gas sensing mechanisms of noble-metal-modified WO₃ composite nanostructures have been introduced. The photocatalytic properties of noble-metal-modified WO₃ composite nanostructures are reviewed according to the species of noble metals（such as Au，Ag，Pt and Pd nanoclusters）. The recent achievements in improving the photocatalytic performance of noble-metal-modified WO₃ composite nanocatalysts and the related photocatalytic mechanisms have been summarized. Some existing issues and future trends in development of the noble-metal-modified WO₃ compositephotocatalysts have been also included.

Key words: WO₃ nanocrystals, noble metal nanoclusters, gas-sensing properties, gas-sensing mechanism, photocatalytic properties, photocatalytic mechanism

摘要： WO₃作为新型的气敏材料和光催化剂具有广阔的应用前景，通过贵金属纳米簇修饰后的WO₃复合纳米晶比WO₃基体材料在性能上大幅提高。本文综述了贵金属修饰对WO₃基体气敏和光催化性能的影响，其中气敏性能以不同敏感气体（如NO_x、H₂S、H₂等）为分类依据，而光催化性能以不同贵金属（Au、Ag、Pt等）添加剂为分类依据，系统综述了贵金属/WO₃复合纳米晶的气敏和光催化性能研究最新进展，并总结了常见贵金属/WO₃的气敏和光催化机理模型，提出了贵金属/WO₃在气敏和光催化应用过程中存在的问题及前景展望。

关键词: WO₃纳米晶, 贵金属纳米晶簇, 气敏性能, 气敏机理, 光催化性能, 光催化机理