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This article describes a straightforward chemical procedure that involves hydrothermal and ultrasonic treatments to create a new 2D/2D ultrathin WO3/Ti3C2 heterojunctions. The features of the fabricated heterojunctions were characterized and examined by field emission electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), optical absorption spectroscopy (UV–Vis). By photodegrading an organic dye under the influence of visible light, the photocatalytic degradation capabilities of the heterojunctions were also investigated. The performance of WO3/Ti3C2 was superior to that of bare WO3, with a removal rate of 94% and a kinetic rate constant (k) that was approximately 3 times that of WO3. The creation of 2D/2D heterojunction was observed to encourage the spatial charge separation and increase the surface reactive sites, to result with the increased photocatalytic activity in WO3/Ti3C2 heterojunction. The photocurrent values discovered through photoelectrochemical studies further indicated Ti3C2′s active function in enhancing water-splitting performance. The impedance analysis examined by an electrochemical method revealed that heterojunctions might be helpful in accelerating the migration of charges quickly to get the outcomes seen.

Molybdenum trioxide (MoO3) have gained considerable attention for their wide applications ranging from optoelectronics, solar cells to energy storage. Herein, we obtained high crystalline MoO3 nanosheets (NSs) through a vapor phase epitaxy (VPE) method. A photodetector (PDs) based on MoO3 NSs was fabricated on the SiO2/Si substrate and the PDs exhibit a striking photoresponse under ultraviolet (UV) light. Furthermore, by introducing a CsPbBr3 QDs the photocurrent of the MoO3 devices was enhanced by 2 orders of magnitude than the pristine counterpart. The enhanced photocurrent could be ascribed to the interfacial charge transfer from CsPbBr3 QDs to MoO3. The hybrid CsPbBr3 QDs/MoO3 photodetectors exhibit high responsivity with high on/off ratio under UV light illumination. Furthermore, the performance of the hybrid device, extending from UV to visible light, has ensured broad spectral response of the device. This work indicates that CsPbBr3 QDs/MoO3 hybrids can be promising for the construction of broad band photodetectors and other optoelectronic devices.

Here in, we report the fabrication of thin two dimensional (2D) ZnO nanosheets (NSs) flexible piezo-phototronic ultraviolet (UV) photodetector (PD). The morphological and optical properties of the as-synthesized ZnO NSs is characterized in detail. The flexible Ag–ZnO NSs-Ag lateral PDs are fabricated on the polyethylene terephthalate (PET) substrate. A striking photoresponse is observed for 2D-ZnO under UV illumination. Furthermore, by introducing a strain (in the form of bending) the photocurrent and responsivity of this PD can be modulated via piezo-phototronic effect, emerging from the ZnO nanosheets. The photocurrent enhancement under bending could be attributed to the piezo polarization charges produced at ZnO/Ag interface due to strain. This piezo polarization charges result in the modulation of Schottky barrier (SB) height at the semiconductor/metal interface and induce improved photogenerated charge carriers and reduced recombination probability to result enhanced performances from the ZnO NSs photodetector. The physical mechanism involved in the enhancement of photocurrent via piezo-phototronic is proposed to explain change in SB height at semiconductor/metal interface using the band diagrams. This results demonstrates an efficient prototype of the piezo-phototronic PD based on thin ZnO NSs, which provides an effective pathway to enhance the performance of optoelectronic devices.

Tin sulfides are promising materials in the fields of photoelectronics and photovoltaics because of their appropriate energy bands. However, doping in SnS2 can improve the stability and robustness of this material in potential applications. Herein, we report the synthesis of SnS2 nanoflakes with Zn doping via simple hydrothermal route. The effect of doping Zn was found to display a huge influence in the structural and crystalline order of as synthesized SnS2. Their optical properties attest Zn doping of SnS2 results in reduction of the band gap which benefits strong visible-light absorption. Significantly, enhanced photoresponse was observed with respect to pristine SnS2. Such enhancement could result in improved electronic conductivity and sensitivity due to Zn doping at appropriate concentration. These excellent performances show that Sn1−xZnxS2 nanoflakes could offer huge potential for nanoelectronics and optoelectronics device applications.

ZnO/Plasmonic noble metal heterostructures promise the visible light functioning photocatalysis. Here we report, silica supported ZnO/Au heterostructures for recyclable visible light photo-degradations under sun light. Firstly, silica supported ZnO nanostructures was obtained by thermal decomposition of surface adsorbed zinc acetate molecules. Further, the Au nanoparticles were formed on SiO/ZnO in successive ionic layer adsorption and reaction process. Electron microscopic images obtained for the nanocomposite indicated the ZnO layers of ~ 30 nm and Au nanoparticles of ~ 5 nm on silica surface. Absorption spectrum of the nanocomposite indicated the bandgap value of ZnO grown on silica as 3.44 eV. Remarkably, absorption of visible region photons have got enhanced ~ 7 times for the Au nanoparticles incorporation in the silica/ZnO composite. The photocatalytic degradation of methylene blue conducted for the silica/ZnO/Au nanocomposite under sunlight have showed the 4-5 times enhanced photocatalytic effect over silica/ZnO nanocomposite. The manifestations of electron transfer from the Fermi level of Au to the ZnO facilitates the visible light functioning of the catalyst. In addition, the silica/ZnO/Au catalyst have showed the adequate efficiency in the recycled reactions. [ABSTRACT FROM AUTHOR]