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The vital issue for semiconductor pressure sensors is how to improve the sensitivity of their piezoresistive behavior. In this work, aiming to substantially promote the sensitivity, ZnO/SiC nanowire heterojunctions with various ZnO piezoelectric shell thicknesses were constructed by adjusting the depositing times of atomic layer deposition (ALD). It was found that the thicknesses of coupled ZnO nanolayers played a profound effect on the response of the heterojunctions to the change of stresses, representing the tailored piezoresistive behaviors. Accordingly, the piezoresistive coefficient was optimized to ~ 9.47 × 10–11 Pa−1 with an enhanced ΔR/R0 value of ~ 0.88, once the ZnO nanolayer thickness is fixed at ~ 20 nm, superior to most of pressures sensors based on SiC nanomaterials. This work may provide a novel strategy for exploring advanced SiC-based pressure sensors by coupling with suitable thickness of the piezoelectric nanolayer to improve piezoresistive behaviors. The tailored piezoresistive performance of ZnO/SiC nanowire heterojunctions with a adjusted shell thicknesses of ZnO piezoelectric nanolayers was reported, which had an enhanced piezoresistive coefficient of 9.47 × 10–11 Pa−1 and a ΔR/R0 of 0.88. [ABSTRACT FROM AUTHOR]

The tailored doping levels towards the band gap tunability are one of the challenges to push forward the potential application of one-dimensional (1D) ZnO nanostructures in the opto/electric nanodevices. In present work, we reported the exploration of Mg-doped ZnO nanofibers via electrospinning of polyvinylpyrrolidone (PVP), Zn(CH 3 COO) 2 (ZnAc) and Mg(CH 3 COO) 2 (MgAc), followed by calcination in air. The resultant products were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscope (HRTEM), and X-ray photoelectron spectroscopy (XPS). The optical measurements (UV–vis) of the Mg-doped ZnO nanofibers suggested that the optical band gaps of the ZnO nanofibers could be tuned from 3.33 to 3.40 eV as a function of the Mg doing levels. This tunability of the band gap of ZnO nanofibers with an intentional impurity could eventually be useful for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Constructing semiconductor heterojunction with optimal structure and composition is highly desired to maximize the solar light utilization for photoelectrochemical (PEC) water splitting. Here, we reported the fabrication of BiVO 4 @ZnO heterojunction with a novel nanostructure for PEC water splitting via foaming-assisted electrospinning and subsequent atomic layer deposition (ALD) techniques. In such BiVO 4 @ZnO heterojunction, the isolated BiVO 4 nanoparticles were packaged within the ZnO microbelt matrix. During PEC water splitting, the BiVO 4 acts as the primary light absorber for wider solar spectral harvesting, and the ZnO prompts the transfer of the photo-excited high-energy electrons, which would render them with prolonged lifetime and enhanced separation of the photogenerated charge carriers. In addition, the microbelts architecture with a hollow channel can also effectively improve the interfacial charge separation and transportation. Accordingly, the PEC performances of BiVO 4 @ZnO hybrid microbelts were significantly enhanced with a photocurrent density up to ∼0.46 mA cm −2 (at 1.23 V vs. reversible hydrogen electrode (RHE) under simulated sunlight illumination), which is 15.3 times to that of pure BiVO 4 counterpart (∼0.03 mA cm −2 ). The photocurrent density of the BiVO 4 @ZnO electrode can be further increased to 1.07 mA cm −2 at 1.2 V vs. RHE by adding hole scavenger (NaSO 3 ) in the electrolyte solution under AM 1.5 G irradiation. [ABSTRACT FROM AUTHOR]