Sonochemical synthesis of ZnO‐ZnS core‐shell nanorods for enhanced photoelectrochemical water oxidation

Abstract

The ultrasonic‐assisted synthesis method provides a fast, simple, and large‐scale route for synthesizing desired materials under ambient conditions. In this work, we report on the facile preparation of ZnO‐ZnS core‐shell nanorods on a fluorine‐doped tin oxide (FTO) substrate. The core‐shell nanorods were synthesized by sequential nanoscale reactions involving the preparation of ZnO nanorods and conversion of the ZnO surface into a ZnS shell on the FTO substrate, using an in situ sonochemical method. The ZnO‐ZnS core‐shell nanorods showed improved photocurrents compared with ZnO nanorods for the water oxidation reaction. During the water oxidation reaction, the ZnS shell passivates the surface‐defects of the ZnO, which results in enhanced charge separation in the ZnO nanorods and higher performance.

Dual II Heterojunctions Metallic Phase MoS2/ZnS/ZnO Ternary Composite with Superior Photocatalytic Performance for Removing Contaminants

“…New binding energyp eaks at 162.08 and 162.05 eV appeared in the highresolution XPS spectrum of S2po fM Z2 and MZ8, respectively. [17] It can be assignedt oSin the ZnS, suggesting the existence of ZnS in the composites, andi sa ffected by the molar of (NH 2 ) 2 CS, which is consistent with the above-mentioned XRD and EDX results. Figure 5s hows the FTIR spectra of ZnO, MoS 2 and different MZ composites.…”

Highly Dispersed Pt Nanoparticle-Doped Mesoporous ZnO Photocatalysts for Promoting Photoconversion of CO2 to Methanol

“…The optical absorption of Pt/ZnO nanocomposites at various Pt concentrations was computed by determining UV–vis absorption spectra compared with the bare ZnO NPs. As seen in Figure a, the bare ZnO NPs showed absorption in the UV region without absorption in visible spectra with an abrupt absorption edge at around 360 nm owing to their high band gap (3.3 eV) . Following bare ZnO NPs, the absorption edges were red-shifted to larger wavelengths at 3.77, 408, 439, and 443 nm over mesoporous 0.5, 1, 1.5, and 2% Pt/ZnO, respectively.…”

“…As seen in Figure 5 a, the bare ZnO NPs showed absorption in the UV region without absorption in visible spectra with an abrupt absorption edge at around 360 nm owing to their high band gap (3.3 eV). 46 Following bare ZnO NPs, the absorption edges were red-shifted to larger wavelengths at 3.77, 408, 439, and 443 nm over mesoporous 0.5, 1, 1.5, and 2% Pt/ZnO, respectively. In general, the integration of Pt NPs into mesoporous ZnO led to the absorption of ZnO in UV light being shifted into the visible-light region.…”

Transparent p–n Junction in Cu2O/ZnS/ZnO Core–Shell Nanoarrays via In Situ Sulfuration for Enhanced Photovoltaic Stability

“…41,53,54 The in situ ZnS shell that covers the ZnO nanoarrays can act as the ladder to accelerate photogenerated carrier transfer while maintaining decent transmittance and increasing carrier injection via its high QY. 41,[48][49][50]62 Moreover, the ZnS/ZnO orderly core−shell nanoarrays can provide a better transport pathway via the (002) preferred growth and increase the solar efficiency via the scattered light collection. 9,23−25 Owing to the synergism between the appropriate Fermi level and high QY of the in situ dual functional ZnS transition layer, and the better carrier transport pathway and higher solar efficiency of ZnS/ ZnO orderly core−shell nanoarrays, the photogenerated carrier would attain a decent kinetic equilibrium to achieve high PCE.…”

“…47 In particular, the core−shell structure can fully leverage the solar energy to increase the quantum efficiency. 48 Ranjith et al fabricated the Ce 2 S 3 :ZnO−ZnS arrays for improving solar efficiency, thereby achieving remarkable photocatalytic properties. 49 Moreover, they fabricated vertical ZnO−ZnS arrays with excellent photosensing performances by adjusting shell wall thickness to improve solar efficiency.…”