The highly efficient photocatalytic and light harvesting property of Ag-TiO2 with negative nano-holes structure inspired from cicada wings

Abstract

The negative replica of biomorphic TiO2 with nano-holes structure has been effectively fabricated directly from nano-nipple arrays structure of cicada wings by using a simple, low-cost and highly effective sol-gel ultrasonic method. The nano-holes array structure was well maintained after calcination in air at 500 °C. The Ag nanoparticles (10 nm–25 nm) were homogeneously decorated on the surface and to the side wall of nano-holes structure. It was observed that the biomorphic Ag-TiO2 showed remarkable photocatalytic activity by degradation of methyl blue (MB) under UV-vis light irradiation. The biomorphic Ag-TiO2 with nano-holes structure showed superior photocatalytic activity compared to the biomorphic TiO2 and commercial Degussa P25. This high-performance photocatalytic activity of the biomorphic Ag-TiO2 may be attributed to the nano-holes structure, localized surface plasmon resonance (LSPR) property of the Ag nanoparticles, and enhanced electron-hole separation. Moreover, the biomorphic Ag-TiO2 showed more absorption capability in the visible wavelength range. This work provides a new insight to design such a structure which may lead to a range of novel applications.

Synthesis and characterization of Ag‐loaded p‐type TiO2 for adsorption and photocatalytic degradation of tetrabromobisphenol A

“…Ag/TiO 2 displays distinct diffraction peaks at 2θ = 25.8°, 37.8°, 48.1°, and 55.2°, which indicate the typical anatase phase of TiO 2 (Cao et al, ). The diffraction peaks of Ag are not obvious, it may be attributed to the low loaded content of Ag nanocrystals, and the (111) plane of Ag (2θ = 37.8°) overlaps with the diffraction peaks of the TiO 2 (004) plane (Lian et al, ; Zada et al, ). The peaks of TiO 2 were not disturbed by Ag, and the lack of change indicated that Ag did not enter the lattice of TiO 2 (Zada et al, ).…”

“…The diffraction peaks of Ag are not obvious, it may be attributed to the low loaded content of Ag nanocrystals, and the (111) plane of Ag (2θ = 37.8°) overlaps with the diffraction peaks of the TiO 2 (004) plane (Lian et al, ; Zada et al, ). The peaks of TiO 2 were not disturbed by Ag, and the lack of change indicated that Ag did not enter the lattice of TiO 2 (Zada et al, ). The UV–Vis spectrum of the Ag/TiO 2 photocatalysts is shown in Figure b; D‐TiO 2 showed slightly higher absorbance than Ag/TiO 2 in the UV light region, which might be due to the abundance of TiO 2 (Zhang, Zhou, Bao, Zhang, & Sheng, ).…”

“…Additionally, with a range of doping and heterojunctions, TiO 2 can be used to degrade various organic pollutants under UV–visible (λ > 360 nm) or visible light (λ > 420 nm) as well. However, the main pollutants that are targets for degradation are dyes and phenol‐like organic pollutants (Lee et al, ; Likodimos, ; Xing et al, ; Zada et al, ; Zalfani et al, ; Zhang, Li, Li, Li, & Yang, ). Studies on the degradation of emerging contaminants (ECs) under UV–visible or visible light are few.…”

Biomimetic Polymer Surfaces by High Resolution Molding of the Wings of Different Cicadas

“…Methods such as replica molding or etching allow functional surface topography to be transferred to relevant surfaces where their beneficial properties can be studied [22][23][24][25]. The molding of surfaces that are covered in nano-and micron-scale features has already been achieved using various techniques such as soft lithography, photolithography, injection molding, hot embossing, atomic layer deposition, capillary force lithography and ultraviolet nanoimprint lithography (NIL) [26][27][28][29][30][31][32][33][34][35]. Depending on the molding polymer and technique employed, feature resolutions of 100 nm can be achieved, with reports of features as small as 6 nm in diameter [36][37][38].…”

Facile in-situ growth of Ag/TiO2 nanoparticles on polydopamine modified bamboo with excellent mildew-proofing

“…However, bare TiO 2 suffers from low efficiency and narrow light-response range which restrict its application in solar light photocatalysis 21–23 . Furthermore, the agglomeration of TiO 2 nanoparticles could significantly decrease their photocatalytic activity, and highly-dispersed TiO 2 nanoparticles are desirable.…”