One‐Pot Synthesis of Au Embedded ZnO Nanorods Composite Heterostructures with Excellent Photocatalytic Properties

Abstract

Here, we have designed a noble composite nanostructure by embedding gold (Au) nanoparticles into zinc oxide (ZnO) nanorods surface in one pot synthesis as a photocatalyst. The formation the composite nanostructure was confirmed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy and transmission electron microscopy investigations. Microscopic studies suggest that spherical Au nanoparticles are nucleated on the ZnO nanorods surface. XPS shows shifting of peak positions towards higher binding energy which indicates charge transfer from ZnO to Au in the composite nanostructures. This is unambiguously confirmed by the steady state spectroscopic studies. It was found that 95.7% (1.8 3 10 À5 mM) of Methylene blue dye is degraded by the composite nanostructure after 140 min under UV light illumination and the apparent rate constant was found to be 0.015 min À1 . This new class of Au nanoparticles embedded ZnO nanorods composite nanostructure opens up new possibilities in photocatalytic, solar energy conversion, photovoltaic, and other new emerging applications.

Green Approach for the Fabrication of Au/ZnO Nanoflowers: A Catalytic Aspect

“…The blue shift of the excitonic band (ZnO) in nanoflowers compared to pure ZnO (367 nm) is because of the interaction of ZnO on the Au surface. 27,28,33,71 As demonstrated earlier, the high dielectric constant of the ZnO, TiO 2 , SnO 2 , and CdSe or CdTe shell causes a red shift in the plasmonic peak of Au. 27,28,72−82 3.2.…”

“…However, the absorption peaks at 377 and 343 nm are attributed to excitonic bands for ZnO and Au/ZnO nanoflowers, respectively. The blue shift of the excitonic band (ZnO) in nanoflowers compared to pure ZnO (367 nm) is because of the interaction of ZnO on the Au surface. ,,, As demonstrated earlier, the high dielectric constant of the ZnO, TiO 2 , SnO 2 , and CdSe or CdTe shell causes a red shift in the plasmonic peak of Au. ,,− …”

“…So, development of a mild and efficient method for the reduction of nitro compounds is highly needed. Recently, substances composed of novel metal and metal oxide semiconductor-based nanomaterials have drawn enormous attention in catalysis science by material researchers, especially in organic transformation because of their high effectiveness as heterogeneous catalysts in various liquid phase processes. − Till date, various particular hybrid structures made out of gold (Au) and zinc oxide (ZnO) have been studied, for example, nanopyramids, linear and branched hybrid nanocrystals, urchins, hollow spheres, hybrid nanopyramids, yolk–shell nanospheres, , and core–shell nanostructures, − and the creation of these Au/ZnO hybrid nanostructures has been accomplished by utilizing different physical and chemical procedures, for example, microwave light, sol–gel method, coprecipitation, solution method, solvothermal, ,, chemical vapor deposition, and so forth. All previously mentioned fabrication procedures are profoundly costly and use different risky materials.…”

Porous ZnO Microspheres Grafted with Poly‐(N‐isopropylacrylamide) via SI‐ATRP: Reversible Temperature‐Controlled Switching of Photocatalysis**

“…[19][20][21] Studies have shown that the structure and morphology of ZnO, as a key factor, can significantly influence photocatalysis activities. [22][23][24] Recently, enormous efforts have been devoted to designing ZnO with various particles sizes and morphologies suitable for photocatalysis, including nanorods, [25] nanowires, [26] nanoribbons, [27] nanotubes [28] and three-dimensional (3D) ZnO micro/ nanostructures. [29] Especially, hierarchical 3D ZnO nanostructures are of significant interest since their novel architectural structures provide large surface area, [30] good permeability and high interfacial charge-transfer efficiency, [31,32] leading to the enhanced photocatalysis performance.…”

Novel Green Approach for Fabrication of Ag2CrO4/TiO2/Au/r-GO Hybrid Biofilm for Visible Light-Driven Photocatalytic Performance

“…Various approaches have been utilized for the impregnation of noble metal nanoparticles in semiconductor nanostructures for visible light-driven photocatalysis, especially gold nanoparticles because of its chemical stability, intrinsic photostability during the catalytic process, and size- and shape-dependent optical sensitivity. , Several synthetic procedures, for example, hydrothermal, seed-mediated growth process, glancing-angle deposition, thermal decomposition, and sol–gel process, have been incorporated to fabricate the noble metals decorated heterostructured nanocrystals. Until now, many research groups have reported metal-decorated systems such as Pd-decorated m-BiVO 4 /BiOBr, Au-decorated V 2 O 5 @ZnO, Pd-decorated ZnO-expanded graphite, Pt-decorated PdCo@Pd/C core–shell nanoparticles, and so forth.…”