Hongbing Lu

Porous NiO–WO3 heterojunction nanofibers fabricated by electrospinning with enhanced gas sensing properties

A series of NiO–WO3 composite nanofibers with different molar ratios (Ni/W = 0%, 1%, 3% and 5%) were fabricated based on an electrospinning and calcination technique. The gas sensing performances of sensors based on the as-produced nanofibers were studied towards acetone in detail. Compared with the pure WO3 nanofibers, the porous NiO–WO3 composite nanofibers exhibited higher sensitivity, faster response, and shorter recovery time towards acetone. Particularly, the 3 mol% NiO–WO3 heterojunction nanofibers demonstrated the largest sensitivity, exhibiting a prominent value of 22.5 under 100 ppm acetone at the operating temperature of 375 °C, which is almost 2.1 times larger than that of the pure WO3 nanofibers. Moreover, the 3 mol% NiO–WO3 heterojunction nanofibers also exhibited excellent selectivity and long-term stability to acetone. The combined effects including the formation of p–n heterojunctions between NiO and WO3, high oxygen species absorbing capacity, and special porous structural features with high surface area and small grain size, contributed to the enhanced sensing properties of the 3 mol% NiO–WO3 composite nanofibers. These attractive gas sensing properties enable the NiO–WO3 heterojunction nanofibers to be a promising material for application in gas sensors.

Enhanced photocatalytic activity of flowerlike CuO–ZnO nanocomposites synthesized by one-step hydrothermal method

Flowerlike CuO–ZnO nanocomposite photocatalysts with different molar ratios of Cu to Zn, have been fabricated using a facile one-step hydrothermal method. The photocatalytic activities of the CuO–ZnO nanocomposites were investigated for their efficiency on the degradation of methyl orange dyes under mercury lamp irradiation, and the results showed that the nanocomposites possessed remarkably enhanced photocatalytic activities. The enhanced photocatalytic activities can be ascribed to the combined effects of suppression of the recombination of photogenerated charge carriers and improved visible light utilization in CuO–ZnO nanocomposites.

Three-dimensionally Hierarchical Bi2WO6 Architectures with Enhanced Photocatalytic Activity

Three-dimensionally hierarchical Bi2WO6 architectures have been produced via a facile and economical hydrothermal method without any template or surfactant. This architecture with flower-like morphology is assembled by numbers of intercrossed nanosheets. Moreover, different Bi2WO6 nanostructures including multilayered disks and irregular nanoplates can also be produced by simply adjusting the pH value of the precursor solution. Importantly, this kind of hierarchically structured Bi2WO6 architecture exhibits a much better photocatalytic activity in the photodegradation of rhodamine B than that of conventional Bi2WO6 multilayered disks and nanoplates. This enhanced photocatalytic performance is mainly attributed to the large specific surface areas, special structural features and high capability of absorbed oxygen species. The present work offers an effective approach for the further improvement of photocatalytic activity by designing a desirable micro/nanoarchitecture.