Matrix phase induced boosting photoactive performance of ZnO nanowire turf‐coated Bi₂O₃ plate composites

Abstract

A new nanocomposite consisting of ZnO nanowire turf-coated Bi 2 O 3 plates was synthesized using a method combining a chemical bath and hydrothermal crystal growth through sputtering ZnO seed layer-assisted growth. Structural analysis revealed that highly crystalline, high-density, one-dimensional (1D) ZnO crystals were uniformly coated on the organized two-dimensional (2D) Bi 2 O 3 plates with a single β phase or dual α/β polymorphic phases. The Bi 2 O 3 -ZnO composites exhibited enhanced absorption properties in the ultraviolet and visible regions compared with pristine Bi 2 O 3 and ZnO. Furthermore, the Bi 2 O 3 -ZnO composites exhibited higher photoactive performance than that of the pristine Bi 2 O 3 and ZnO because of the low recombination rate of photoinduced electron−hole pairs caused by the vectorial transfer of electrons and holes between ZnO and Bi 2 O 3 and the substantially increased surface area of the unique composite morphology. The ZnO nanowire turf-coated Bi 2 O 3 plates with a α/β-Bi 2 O 3 matrix exhibited photoelectrochemical and photocatalytic properties superior to those of the composite with a single β-Bi 2 O 3 matrix. The coexistence of α/β homojunction in the Bi 2 O 3 matrix and the abundant heterojunctions between the ZnO nanowires and Bi 2 O 3 plates substantially enhanced photoexcited charge separation efficiency. Growing high-density 1D ZnO on 2D Bi 2 O 3 via a combination methodology and crystallographic phase control provided a promising material design route for nanocomposite systems with high photoactivity for photoexcited device applications.

Sputtering-Assisted Synthesis of Copper Oxide–Titanium Oxide Nanorods and Their Photoactive Performances

“…Figure 9 b presents the Nyquist plots of various samples measured at the frequency range from 100 kHz to 0.1 Hz and a potential amplitude of 10 mV. The radius of the semicircles in Nyquist plots is associated with the interfacial charge transfer resistance [ 48 ]. Notably, TC350 had the smallest semicircular radius, and the pure TiO 2 nanorod template exhibited the largest semicircular radius, indicating that TC350 had the smallest charge transfer resistance and TiO 2 the largest.…”

Cosputtered SnO2–ZnO composite nanofilms with improved dual function

“…the characteristic absorbance spectrum intensities at an irradiation duration of t and at t = 0, respectively. 18 The dark balance tests were carried out at the equilibrium state of the adsorption-desorption process after 30 min in dark. C/C o decreased by approximately 0.8%, 1.3%, 1%, 0.6%, and 0.3% for SZ40, SZ60, SZ80, SnO 2 , and ZnO under the dark balance conditions, respectively.…”

“…The degradation efficiencies of the MO solution with various thin‐film photocatalysts are summarized in Figure 10E, where C / C o = I t / I o was used to evaluate the degradation degree. C o and C are the initial and residual concentrations of the MO solution at t = 0 and at an irradiation duration of t , while I t and I o are the characteristic absorbance spectrum intensities at an irradiation duration of t and at t = 0, respectively 18 . The dark balance tests were carried out at the equilibrium state of the adsorption–desorption process after 30 min in dark.…”

“…3 The coupling of ZnO nanowires and Bi 2 O 3 plates to form a heterostructure enhanced their photoactivities for photoelectrochemical electrode and photocatalyst applications. 18 Combinational-physical-synthesis-derived ZnO-VO x hybrids exhibited an improved NO 2 gas-sensing ability compared to the pristine ZnO matrix. 19 The integration of SnO 2 and ZnO wide-band-gap oxides is a promising composite system for photosensitive and gas-sensing applications in harsh environments owing to their high chemical and thermal stabilities.…”

“…SnO 2 –WO 3 composite films with an appropriate phase ratio exhibited satisfactory photoactivity and gas‐sensing performance toward ethanol vapor 3 . The coupling of ZnO nanowires and Bi 2 O 3 plates to form a heterostructure enhanced their photoactivities for photoelectrochemical electrode and photocatalyst applications 18 . Combinational‐physical‐synthesis‐derived ZnO–VO x hybrids exhibited an improved NO 2 gas‐sensing ability compared to the pristine ZnO matrix 19 …”