Solution Grown Single-Unit-Cell Quantum Wires Affording Self-Powered Solar-Blind UV Photodetectors with Ultrahigh Selectivity and Sensitivity

Abstract

As crystalline semiconductor nanowires are thinned down to a single-unit-cell thickness, many fascinating properties could arise pointing to promising applications in various fields. A grand challenge is to be able to controllably synthesize such ultrathin nanowires. Herein, we report a strategy, which synergizes a soft template with oriented attachment (ST-OA), to prepare high-quality single-unit-cell semiconductor nanowires (SSNWs). Using this protocol, we are able to synthesize for the first time ZnS and ZnSe nanowires (NWs) with only a single-unit-cell thickness (less than 1.0 nm) and a cluster-like absorption feature (i.e., with a sharp, strong, and significantly blue-shifted absorption peak). Particularly, the growth mechanism and the single-unit-cell structure of the as-prepared ZnS SSNWs are firmly established by both experimental observations and theoretical calculations. Thanks to falling into the extreme quantum confinement regime, these NWs are found to only absorb the light with wavelengths shorter than 280 nm (i.e., solar-blind UV absorption). Utilizing such a unique property, self-powered photoelectrochemical-type photodetectors (PEC PDs) based on the ZnS SSNWs are successfully fabricated. The PDs after interface modification with TiO2 exhibit an excellent solar-blind UV photoresponse performance, with a typical on/off ratio of 6008, a detectivity of 1.5 × 1012 Jones, and a responsivity of 33.7 mA/W. This work opens the door to synthesizing and investigating a new dimension of nanomaterials with a wide range of applications.

The Synthesis of Sub-Nano-Thick Pd Nanobelt–Based Materials for Enhanced Hydrogen Evolution Reaction Activity

“…Our current analysis is not limited to specific material systems and rationalized many anisotropic structures reported in the literature. 9,[18][19][20][21][22] Besides, Pd(0.9) and eePtPd showed much-enhanced hydrogen evolution reaction (HER) activities, compared with the commercial Pd black. Moreover, the eePtPd NBs even showed 3.5 times higher exchange current density, defined as the rate of oxidation-reduction reactions at an equilibrium electrode (I o ), compared with those of the commercial Pt catalysts in HClO 4 solutions.…”

Recent Advances in Zinc‐Containing Colloidal Semiconductor Nanocrystals for Optoelectronic and Energy Conversion Applications

“…The results reveal that colloidal zinc chalcogenide nanocrystal‐containing photodetectors are advantageous in tuning of the band gap to ensure efficient charge carrier transfer and match the window of detection. Similarly, ZnS nanowires exhibit a solar‐blind UV photoresponse . Recently, the ZnS 2/3 Se 1/3 quantum rods have been proved to possess an enhanced photoresponse compared with pure ZnSe nanorods and ZnS nanorods (Figure c) .…”

A reduced-dimensional polar hybrid perovskite for self-powered broad-spectrum photodetection

“…The time-resolved photoresponse of IMP was carried out at zero bias. As shown in Figure 3d, the rise time and fall time were achieved to be 165 μs and 220 μs (Figure 3d), which are s h o r t e r t h a n t h o s e o f o t h e r r e p o r t e d s e l f -p o w e r e d photodetectors, such as 0.2 s for EA 4 Pb 3 Cl 10 and 0.25 s for ZnS, [49,50] demonstrating the great potential of IMP for future high-speed self-powered detection. In addition, considering the broad-spectrum absorption of IMP, the photoelectric performance under 405 nm, 520 nm and 700 nm were further investigated.…”