Nanoplate-Built ZnO Hollow Microspheres Decorated with Gold Nanoparticles and Their Enhanced Photocatalytic and Gas-Sensing Properties

Abstract

Hierarchical porous ZnO microspheres decorated with gold nanoparticles (AuNPs) were successfully synthesized by a facile solvothermal route. The hierarchical ZnO superstructure was constructed of interconnected nanoplates with numerous voids. Photoluminescence, X-ray photoelectron spectroscopy, and electron paramagnetic resonance measurements demonstrated that the main defects were oxygen vacancies (V(O)(•)) with minor interstitial oxygen (O(i)(-)) in the hierarchical ZnO hollow microspheres. The as-prepared hierarchical ZnO hollow microspheres and the AuNPs used to decorate them were examined for their photocatalytic degradation ability and as gas sensors. The photodegradation results demonstrated that the degradation rate constant on rhodamine B for undecorated ZnO microspheres was 0.43 min(-1), which increased to 1.76 min(-1) for AuNP-decorated ZnO microspheres. The AuNP-functionalized ZnO microspheres displayed superior sensing properties, with a 3-fold enhancement in their gas response to 1 ppb of dibutyl phthalate.

A Review on the Fabrication of Hierarchical ZnO Nanostructures for Photocatalysis Application

“…Ahmad et al [111] synthesized hierarchical flower-like ZnO-Au nanostructures where Au was deposited on ZnO via an electrochemical method. Nanoplate-built ZnO hollow microspheres decorated with Au nanoparticles with enhanced photocatalytic activity were produced by Xia et al [112] through a facile solvothermal route.…”

Fabrication of Hierarchical ZnO@NiO Core–Shell Heterostructures for Improved Photocatalytic Performance

“…Typical semiconductors that have been investigated are TiO 2 [4], ZnO [5–7], Cu 2 O [8, 9], CdS [10, 11], and C 3 N 4 [12]. Among them, ZnO has been the most systemically investigated owing to its high electron mobility, diverse morphologies, ease of preparation, low cost, and non-toxic nature [13, 14].…”

“…Many research groups have looked into improving the separation efficiency of photogenerated carriers and extending the spectral response range via, for example, doping [17], loading noble metals [5, 18–20], and combining with other semiconductors [21–31]. As a potential candidate, nickel oxide, p-type semiconductor material (Eg = 3.5 eV) with a rock salt or cubic structure, has attracted much interest owing to its electronic structure, high hole mobility, and low lattice mismatch with ZnO.…”

Novel Electrochemical Immunoassay for Carcinoembryonic Antigen Using Ferrocenyl Polymer Nanospheres

“…These methods include fluorescence (Tian et al 2012), surface plasmon resonance (Pal, Rashid, and Bisht 2015), electrochemiluminescence (Feng et al 2015), and photoelectrochemical techniques (Hu et al 2013). Electrochemical immunosensors (Shen et al 2015;Zhang et al 2016) offer advantages of low-cost and light weight analysis.…”

“…For example, Tang et al (2013) designed an electrochemical immunoassay employing platinum-cerium oxide hybrid nanocatalysts that were utilized as labels to catalyze the electrochemical signal. Macromolecules have been employed because of their structural characteristics and extensive applications in lithium batteries, medicine, industry, and sensing (Li, Ding, and Xue 2009;Yu et al 2014;Xia et al 2015 synthesized upconverted particles coated with molecularly imprinted polymers as fluorescence probes for the determination of clenbuterol. Lavine et al (2006) also described polymer swelling and used it for chemical sensing.…”