Biotemplated Mesoporous TiO2/SiO2 Composite Derived from Aquatic Plant Leaves for Efficient Dye Degradation

Abstract

Abstract:The biotemplating technique is an environmental-protective high-efficiency new technology by which the resulting TiO 2 may simultaneously attain the duplication of structure and self-doping elements from biotemplate materials, which is highly desirable for photocatalytic applications. In this paper, aquatic plant leaves-including reed, water hyacinth, and duckweed-were used as both templates and silicon precursors to successfully synthesize biomorphic TiO 2 /SiO 2 composite with mesoporous structures. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N 2 adsorption-desorption, and UV-visible diffuse reflectance spectra were applied to characterize the microstructures of the samples. The results show that all TiO 2 /SiO 2 composites are mainly composed of an anatase phase with mesoporous structure and possess high specific surface area. Compared with commercial Degussa P25 TiO 2 , all TiO 2 /SiO 2 samples display intensive light-harvesting efficiency, particularly in the visible light range. The activities were evaluated by using gentian violet as a target for photocatalytic degradation experiments under simulated solar irradiation. The TiO 2 /SiO 2 samples templated by reed and water hyacinth leaves exhibit high activity, while the TiO 2 /SiO 2 samples obtained from duckweed are inferior to P25 in the degradation of gentian violet. A synergistic effect of SiO 2 incorporation and structural construction through biotemplating is proposed to be beneficial to photocatalytic activity.

Bio-Templating: An Emerging Synthetic Technique for Catalysts. A Review

“…The photocatalytic activity of TiO 2 /SiO 2 samples was compared to that obtained with P25 and non-templated TiO 2 under simulated sunlight irradiation. The results showed that the photocatalytic activity of samples prepared by biotemplating was higher than that obtained by the other photocatalysts (degradation yields of 72.0% and 61.4% of templated samples vs. 42.4% and 24.5% of P25 and TiO 2 particles prepared with no template, respectively), and that it depended on the type of plant [20].…”

“…Another virus that has been used as a pattern for biotemplating approaches is the M13 phage, as its genetically engineered mutants present modifications on the surface that bind to nanoparticles or nanotubes, improving the functionality of the material [17]. Wood [18], cotton [19], aquatic plants [20], green leaves [1,21], or even animal products [22] have also been used as templates. Butterfly wings are of great interest as they present an intricate and complex microstructure and photonic resonances that control their structural color and make them very suitable for catalysis and electrochemical applications [23][24][25].…”

Facile Synthesis of Eggshell Membrane-Templated Au/CeO2 3D Nanocomposite Networks for Nonenzymatic Electrochemical Dopamine Sensor

“…As an agricultural waste, it is estimated that more than 7.0 million tons of eggshell waste in the world were produced every year [23]. ESM is one of the most widely used natural biological templates, and its unique 3D network structure provides its natural advantages with low cost and non-toxicity as a supporting template [24], compared to other biological templates, such as bacterial virus templates [25], algae templates [26], plant templates [27], and DNA templates [28]. The main advantage of ESM is that it has a wide range of sources, low cost, no pollution to the environment, and simple separation and purification process [29].…”

Low-Temperature Sol-Gel Synthesis of Nitrogen-Doped Anatase/Brookite Biphasic Nanoparticles with High Surface Area and Visible-Light Performance

“…The intimate contact can facilitate inter particle charge transfer from brookite to anatase and reduce the recombination of electron-hole pairs. Thirdly, the large surface area can provide more active sites and improve the diffusion and migration of MO in the process of photodegradation [36]. Furthermore, the competitive diffusion of the H 2 O and dye molecules, dye molecule structure, and photocatalytic degradation route are also the factors influencingthe photocatalytic process [37].…”