Publications by authors named "Qinwei An"

Transition metal dichalcogenide (TMD) nanotubes offer a unique platform to explore the properties of TMD materials at the one-dimensional limit. Despite considerable efforts thus far, the direct growth of TMD nanotubes with controllable chirality remains challenging. Here we demonstrate the direct and facile growth of high-quality WS and WSe nanotubes on Si substrates using catalytic chemical vapour deposition with Au nanoparticles.

View Article and Find Full Text PDF

The involvement of heterogeneous solid/liquid reactions in growing colloidal nanoparticles makes it challenging to quantitatively understand the fundamental steps that determine nanoparticles' growth kinetics. A global optimization protocol relying on simulated annealing fitting and the LSW growth model is developed to analyze the evolution data of colloidal silver nanoparticles synthesized from a microwave-assisted polyol reduction reaction. Fitting all data points of the entire growth process determines with high fidelity the diffusion coefficient of precursor species and the heterogeneous reduction reaction rate parameters on growing silver nanoparticles, which represent the principal functions to determine the growth kinetics of colloidal nanoparticles.

View Article and Find Full Text PDF

Rhenium disulfide (ReS2) is a recently discovered next-generation transition metal dichalcogenides (TMDs) material that exhibits unique properties, which have resulted in its wide use in the fabrication of electronic and optoelectronic devices. Studies on ReS2 have mainly focused on the synthesis and applications of two-dimensional (2D) materials, while studies on one-dimensional (1D) ReS2 have yet to be reported. Herein, 1D single-crystal ReS2 nanowires have been synthesized successfully for the first time via chemical vapor deposition (CVD) and utilized as the active layer in a nanostructured photodetector.

View Article and Find Full Text PDF

In this study, we design and demonstrate a novel type of self-powered UV photodetectors (PDs) using single-crystalline ZnS nanotubes (NTs) as the photodetecting layer and Ag nanowires (NWs) network as transparent electrodes. The self-powered UV PDs with asymmetric metal-semiconductor-metal (MSM) structure exhibit attractive photovoltaic characteristic at 0 V bias. Device performance analysis reveals that the as-assembled PDs have a high on/off ratio of 19173 and a fast response speed (τ = 0.

View Article and Find Full Text PDF

ZnS nanotubes (NTs) were successfully prepared via a one-step thermal evaporation process without using any templates. The resulting NTs were single crystalline and structurally uniform. Based on experimental analysis, a tube-growth vapor-liquid-solid process was proposed as the growth mechanism of ZnS NTs.

View Article and Find Full Text PDF

Long and single-crystalline CdS nanotubes (NTs) have been prepared via a physical evaporation process. A metal-semiconductor-metal full-nanostructured photodetector with CdS NTs as active layer and Ag nanowires (NWs) of low resistivity and high transmissivity as electrodes has been fabricated and characterized. The CdS NTs-based photodetectors exhibit high performance, such as lowest dark currents (0.

View Article and Find Full Text PDF