Stimulated generation of photobiogas by morphologically tuned nanostructured ZnO and ZnO/TiO2

Abstract

The photocatalytic degradation (PCD) of ethanol in an inert atmosphere on catalysis was explored in a lab-scale experiment. A morphologically tuned nanostructured controlled ZnO and ZnO/TiO2 nanocomposites were synthesized using a simple hydrothermal process under the control of several functionally capping agents marking a milestone in photocatalysis. It is possible that this could be modified to produce photobiogas out of organic dye pollution. The photocatalysts were characterized by the use of X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer, Emmett, and Teller (BET) surface area analyzer, Scanning electron microscope (SEM-EDX), and UV–Vis absorption spectroscopy. The photocatalytic activity of the ZnO and ZnO–TiO2 composite nanostructures was evaluated for the photodegradation of the Tartrazine (Tr) dye aqueous solution. Where the composite matrix exhibits higher photocatalytic activity than pure ZnO nanomaterials as a result of the synergistic interaction between ZnO and TiO2 particles. This is mainly due to its higher surface area than pure ZnO. Moreover, the photocatalytic activity of the tuned nanostructured materials is found to be enhanced by the effect of the capping agent and controlling the morphology. This increase is accompanied by a significant shift in surface shape and band gap energy. According to the findings, the designed morphologies of pure ZnO photocatalyst impacted the formation of photobiogas from the photocatalytic decomposition of ethanol as a model of organic pollutants in wastewater. However, when using composite ZnO/TiO2 photocatalysts, the rate of CH4 formation is significantly lower than when using ZnO photocatalysts alone. This may be attributed to the synergetic effect between ZnO and TiO2 particles which leads to a remarkable reduction in the newly formed band gap energy. This may result in a fast rate of recombination between the photogenerated charge carriers (e− and h+).

Enhanced Photocatalytic Degradation of Methylene Blue Using Ti-Doped ZnO Nanoparticles Synthesized by Rapid Combustion

“…Nevertheless, the low surface area also decreases the charge transfer affecting the recombination, which diminishes the photocatalytic performance [ 13 ]. To overcome this issue, several studies have presented various kinds of strategies to increase the surface area and reduce the recombination of ZnO photocatalysts [ 14 , 15 , 16 ]. The application of ZnO doped with an alkaline earth metal, such as barium (Ba), was reported as the photocatalyst [ 14 ].…”

“…The Pd-ZnO NPs showed excellent photocatalytic degradation performance, better than that of pure ZnO by around 1.9 times due to the increased surface area. Another interesting photocatalyst structure of ZnO/TiO 2 composites was synthesized using a hydrothermal process with different capping agents, including cetyltrimethylammonium bromide (CTAB), acetylacetone (ACAC), and poly (4-styrene sulfonic acid) (PS) [ 16 ]. The composites prepared with ACAC showed a considerable surface area of 217.08 m 2 /g in comparison with that of 14.05 m 2 /g for pure ZnO.…”

Viable production of hydrogen and methane from polluted water using eco-friendly plasmonic Pd–TiO2 nanocomposites

“…In recent years, gases derived from fossil energy, such as CH 4 and H 2 , have gained considerable attention as a "greener" renewable energy source. 1,2 As an alternative to nonrenewable energy sources, fuel-energy gases offer several advantages over conventional energy sources, including their reliability, costeffectiveness, and environmental friendliness. 1,3 Providing fuel gases for ecological sustainability and energy challenges through solar-driven photocatalysts has become an essential solution.…”

Eu3+:Y2Ti2O7 nanomaterials as efficient photocatalysts used for hydrogen and biogas production toward a sustainable environment

“…The photocatalytic method that depends on nano‐photocatalysts can be applied for any type of organic resources regardless of its toxicity 1 . Therefore, the production of hydrogen and biogas as a source of energy from organic matter using nano‐photocatalyst has attracted the attention of researchers 1,4–15 …”

“…1 Therefore, the production of hydrogen and biogas as a source of energy from organic matter using nano-photocatalyst has attracted the attention of researchers. 1,[4][5][6][7][8][9][10][11][12][13][14][15] One of the most often used photocatalysts is pyrochlore. Pyrochlore has the general formula A 2 B 2 O 7 with Fd3m space group, which results in eight formula units in a face-centered cubic unit cell.…”