Y. Chen

Bio: Y. Chen is an academic researcher from Northwest University for Nationalities. The author has contributed to research in topics: Nanostructure & Electrospinning. The author has an hindex of 8, co-authored 11 publications receiving 249 citations.

Excellent acetone sensor of La-doped ZnO nanofibers with unique bead-like structures

Abstract: In this work, Lanthanum (La) doped ZnO nanofibers with bead-like structures were facilely produced by electrospinning technique. The obtained La-doped ZnO products were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller method, transmission electron microscopy and X-ray photoelectron spectroscopy (XPS). The results show that La doping changes the structures of ZnO nanofibers markedly. La-doped ZnO nanofibers have unique bead-like nanostructures, in which two phases of hexagonal La2O3 and wurtzite ZnO coexist along with partially incorporation of La into ZnO lattice. The gas sensing performances of the La-doped ZnO nanostructures to acetone were investigated via static gas sensor testing system. The sensing test results indicate that an appropriate amount of La doping greatly improves the gas sensing properties of ZnO nanofibers. The 1.0 wt% La-doped ZnO sensor has the highest selectivity and response (64, to 200 ppm acetone at 340 °C), in addition to its short response time and recovery time. The unique bead-like structure and the gas sensing mechanism of La-doped ZnO nanofibers are discussed. The La-doped ZnO nanostructures we have produced can be used as a promising material for acetone sensors.

An excellent triethylamine (TEA) sensor based on unique hierarchical MoS2/ZnO composites composed of porous microspheres and nanosheets

Abstract: A convenient two-step hydrothermal method was used to prepare unique hierarchical MoS2/ZnO composites composed of porous microspheres and nanosheets The gas sensing properties of MoS2/ZnO composite sensor was investigated Compared with pure MoS2, the MoS2/ZnO composite sensor shows a remarkably increased response of 2357 to triethylamine (TEA) In addition, the much shorter recovery time for MoS2/ZnO sensor is a sharp contrast to the terribly bad desorption ability of pure MoS2 The prepared MoS2/ZnO gas sensor can achieve a recovery rate of over 90 % after 134 s without using auxiliary means The composite material also presents strong anti-interference ability and outstanding selectivity The excellent sensing performances of MoS2/ZnO composite sensor may be attributed to the n-n composite heterojunction and the abundant diffusion channels originated from the unique microstructure Our research work may provide a valuable strategy for preparing high-performance TEA sensor with low-cost

Rare-Earth Doping in Nanostructured Inorganic Materials.

Abstract: Impurity doping is a promising method to impart new properties to various materials. Due to their unique optical, magnetic, and electrical properties, rare-earth ions have been extensively explored as active dopants in inorganic crystal lattices since the 18th century. Rare-earth doping can alter the crystallographic phase, morphology, and size, leading to tunable optical responses of doped nanomaterials. Moreover, rare-earth doping can control the ultimate electronic and catalytic performance of doped nanomaterials in a tunable and scalable manner, enabling significant improvements in energy harvesting and conversion. A better understanding of the critical role of rare-earth doping is a prerequisite for the development of an extensive repertoire of functional nanomaterials for practical applications. In this review, we highlight recent advances in rare-earth doping in inorganic nanomaterials and the associated applications in many fields. This review covers the key criteria for rare-earth doping, including basic electronic structures, lattice environments, and doping strategies, as well as fundamental design principles that enhance the electrical, optical, catalytic, and magnetic properties of the material. We also discuss future research directions and challenges in controlling rare-earth doping for new applications.

High sensitive and low-concentration sulfur dioxide (SO2) gas sensor application of heterostructure NiO-ZnO nanodisks

Abstract: This paper reports the synthesis and characterization of NiO-ZnO nanodisks synthesized through a facile hydrothermal method. The morphological characterizations confirmed the formation of well-defined nanodisks in high density with an average thickness of 60 ± 5 nm. The x-ray diffraction analysis confirmed the well incorporation of the NiO into the matrix of ZnO crystal and the average crystallite size for the NiO-ZnO nanodisks was found to be 39.71 nm. The compositional analysis revealed the formation of pure NiO-ZnO nanostructures. The synthesized NiO-ZnO nanodisks were used as electrode materials to fabricate Sulfur dioxide (SO2) gas sensors and the gas sensor response and recovery times were systematically analyzed with respect to the operating temperatures and the SO2 gas concentration. The observed sensor gas response, response time and recovery time of the fabricated NiO-ZnO nanodisks based gas sensor were 16.25, 52 s and 41 s, respectively, towards 20 ppm SO2 gas at an optimized temperature of 240 °C. Thus, it is believed that the NiO-ZnO nanodisks could be a promising candidate for the fabrication of efficient gas sensors towards toxic and hazardous gases.

Pt nanoparticles decorated SnO2 nanoneedles for efficient CO gas sensing applications

Abstract: Herein, we report the synthesis, characterization, and gas sensing applications of Pt nanoparticles-decorated SnO 2 nanoneedles synthesized through a facile hydrothermal process. The synthesized nanoneedles were characterized for their morphological, structural, compositional and sensing properties using different characterization techniques. The morphological and structural characterizations confirmed the synthesis of well crystalline Pt nanoparticles decorated SnO 2 nanoneedles with tetragonal rutile crystal phase. X-ray photoelectron spectroscopic analysis (XPS) confirmed the spatial distribution of Pt metal into SnO 2 nanoneedles. Further, gas sensor applications of the synthesized nanoneedles were studies at different operating temperatures and concentrations of the CO gas. The detailed CO gas sensing analysis revealed that at an optimized temperature of 250 °C, the sensor exhibited 23.18 gas response with the response and recovery times of 15 s and 14 s, respectively. The long-term stability and the selectivity of the 3.125 at% Pt-decorated SnO 2 nanoneedles were also explored. Finally, a plausible gas sensing mechanism was also proposed.