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Carbon supported oxygen vacancy-rich Co3O4 for robust photocatalytic H2O2 production via coupled water oxidation and oxygen reduction reaction
摘要： Photocatalytic H2O2 production is a promising strategy to alleviate energy crisis since H2O2 is an important liquidus chemical and fuel. However, the following problems severely restrict the development of this technique: (1) low selectivity; (2) low stability (normally less than 5 short-time cycles); (3) fast charge recombination; (4) assistance of hole scavengers and (5) demand of O2 saturation. Herein, carbon supported oxygen vacancy-rich Co3O4 nanoplate (C-ovCo) is reported as an efficient photocatalyst for scavenger-free H2O2 production by coupled 2e– water oxidation (WOR) and 2e? oxygen reduction reaction (ORR) with low energy barrier of 1.1 eV. In this system, the oxygen vacancies can reduce the band gap, enhance the donor density, improve the charge separation and migration and work as WOR sites, while the carbon support accepts electrons and works as ORR sites. The photocatalysts exhibit an optimal H2O2 production rate of 3.78 mmol h–1 g–1 under visible light (λ ≥ 420 nm), an apparent quantum efficiency (AQE) of 16.7% at 420 nm, and a solar-to-chemical efficiency (SCC) of 0.4%. Moreover, the stability of over 720 h (30 long-time cycles) is also superior to the state-of-the-art photocatalytic systems.
关键词： Carbon supported oxygen vacancy-rich Co3O4,Coupled reaction,Photocatalytic H2O2 production,Oxygen reduction reaction,Water oxidation reaction
更新于2025-09-11 14:15:04
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Catalyst-Free Selective Oxidation of Diverse Olefins to Carbonyls in High Yield Enabled by Light under Mild Conditions
摘要： The selective oxidation of ole?ns, in particular, aromatic ole?ns to carbonyls, is of signi?cance in organic synthesis. In general, stoichiometric toxic oxidants or a high-cost catalyst is required. Herein we report a novel and practical light-enabled protocol for the synthesis of carbonlys in high yield through a catalyst-free oxidation of ole?ns using H2O2 as a clean oxidant. A broad scope of carbonyls can be synthesized in high yield, and no catalyst or toxic oxidant is required.
关键词： light-enabled,ole?ns,carbonyls,selective oxidation,H2O2,catalyst-free
更新于2025-09-11 14:15:04
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Quantum Dots for Monitoring Choline Consumption Process of Living Cells via an Electrostatic Force-Mediated Energy Transfer
摘要： In this work, a ratiometric nanoprobe CdS/ZnS-FB was designed for H2O2 detection based on FRET assay. Furthermore, CdS/ZnS-FB could work for detecting choline (Ch) and acetylcholine (ACh) since H2O2 is the enzyme cascade reaction product. Significantly, choline consumption could also be quantitatively measured by monitoring FRET ratio (I522 /I426). Thus, the biosensor could be applied as a universal tool for the detection of choline consumption of living cells, which provides a good potential for the applications in detecting chemical transmitter and cancer diagnosis.
关键词： H2O2,living cells,enzyme cascade reaction,FRET,quantum dots
更新于2025-09-11 14:15:04
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Solid Acids Accelerate the Photocatalytic Hydrogen Peroxide Synthesis over a Hybrid Catalyst of Titania Nanotube with Carbon Dot
摘要： Photocatalytic synthesis of hydrogen peroxide (H2O2) from water and oxygen is an alternative route for clean energy storage and chemical synthesis, but still having problems with insufficient H2O2 productivity and solar-to-chemical energy conversion efficiency. Herein, we reported a hybrid catalyst of proton-form titania nanotube with carbon dot (HTNT-CD) that is highly efficient for the production of H2O2 under visible-light irradiation (λ>420 nm, H2O2 productivity at 3.42 mmol gcat-1·h-1), outperforming the titania catalysts containing noble metals and the carbon nitride catalysts reported previously. Multiple studies demonstrate that the protons on the HTNT-CD are crucial for the production of H2O2 by efficiently accelerating the half reaction of molecular oxygen reduction to form H2O2, and effectively hindering H2O2 decomposition under the irradiation conditions. This HTNT-CD catalyst gives solar-to-H2O2 apparent energy conversion efficiency at 5.2%, which is even 4.9 times of that (1.06%) over the catalyst derived from commercial P25 and CDs. More importantly, the HTNT-CD is stable, giving high H2O2 productivity in the continuous recycle tests.
关键词： photocatalyst,carbon dots,TiO2 nanotubes,H2O2 synthesis
更新于2025-09-10 09:29:36
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Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from Industrial Soil with Solar and UV Light
摘要： The aim of the present study was to evaluate and compare the efficiencies of solar/UV based processes for polycyclic aromatic hydrocarbon (PAH) removal from soils with and without additives. This study provided some useful information to understand the remediation of PAH-contaminated soils by photocatalytic techniques. Soil samples were taken from an industrial area, and PAH removal processes were applied to the samples for 24 h in ambient air conditions. Also, UV experiments (UVA and UVC) were conducted in a specially designed apparatus. TiO2 and H2O2 were used as additives at the doses of 1%, 10%, and 20% of dry soil weight during ambient air experiments. Only 35% 12 PAH removal from soil was obtained in ambient air conditions. This value was calculated as 90% and 86% for UVA and UVC applications, respectively. Results indicated that the use of additives contributed to the photodegradation of PAHs under real conditions. The most efficient doses were 20% for TiO2 (89% PAH removal) and 1% for H2O2 (88% PAH removal). When the removal efficiencies were evaluated in terms of compounds, it was observed that the removal ratios were elevated for both lighter and heavier PAH compounds with the addition of additives. 3-ring and 4-ring PAH compounds were removed at higher ratios in comparison with 5-,6-ring ones for samples with and without additives.
关键词： UV,Ambient air,photodegradation,PAHs,H2O2,TiO2
更新于2025-09-10 09:29:36
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ZnO-CNT Nanostructures as Potential Materials for Non-Enzymatic H <sub/>2</sub> O <sub/>2</sub> Sensing
摘要： Hydrogen peroxide (H2O2) is widely used as an antibacterial, bleaching, decoloring, and oxidizing agent in various industrial fields. However, the exposure to and accumulation of high levels of H2O2 can cause oxidative stress to humans, leading to caducity and diseases due to its unstable and toxic nature. Moreover, H2O2 is a useful indicator for monitoring reactive oxygen species-related diseases in humans because it is generated as an intermediate product of many enzymatic reactions in normal aerobic metabolism. It is therefore essential to develop accurate and reliable methods of detecting H2O2 for industrial and biological purposes. Among the recently established methodologies, non-enzymatic amperometric detection of H2O2 has raised considerable attention owing to its high sensitivity, low cost, ease of operation, and quick response. To improve the electrochemical performance of this method, various redox mediators, especially noble-metal-containing substrates, have been used to fabricate chemically modified electrodes for the non-enzymatic amperometric detection of H2O2. Recently, we have reported many applications of metal oxide-decorated sp2-hybridized carbon nanostructures. Building on our previous studies, we describe herein the use of zinc oxide–carbon nanotubes (ZnO-CNT) for the preparation of modified electrodes exhibiting enhanced electrocatalytic activity for H2O2 reduction.
关键词： Amperometry,H2O2 reduction,ZnO nanoparticle,CNT,Biosensor
更新于2025-09-10 09:29:36
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UV-light intervened synthesis of imidazo fused quinazoline and its solvatochromism, antioxidant, antifungal and luminescence properties
摘要： The photochemical preparation of benzo[4,5]imidazo[2,1-b]quinazoline was assessed under the illumination of UV wavelength (>360 nm). The compound 3,4-dihydronaphthalen-1(2H)-one 1 with 1H-benzo[d]imidazol-2-amine 2 in the existence of KOH/DMF which lead to the aromatized compound 3. The notable remark of this reaction is that the UV irradiation (312 nm) plays a vital part in the formation of the compound, 3 in shorter duration (2h) which resulted in the reaction gave was higher yield (96%). Compound 3 was analyzed by H1, C13 NMR, and HRMS. Solvatochromism impacts of the compound 3 was computed with deference (DCM < methanol< DMF < DMSO). The compound, 3 was presented to invitro free radical screening utilizing DPPH strategy and furthermore H2O2 technique. The standard ascorbic acid has less IC50 value esteem than compound 3. Further, it was subjected to in vitro fungicidal action against two Aspergillus species (A. flavus & niger). The anti-fungal activity of compound 3 additionally demonstrated great action, when compared antifungal specialist Fluconazole.
关键词： solvatochromism,DPPH,UV radiation,anti-fungal,H2O2,antioxidant,Imidazo[2,1-b]quinazoline
更新于2025-09-10 09:29:36
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Applying facilely synthesized CuO/CeO <sub/>2</sub> photocatalyst to accelerate methylene blue degradation in hypersaline wastewater
摘要： Textile and dye effluents have strong color, unstable pH and COD, a lot of inorganic salt, and high biotoxicity. It is difficult and inefficient to remove dyes from high‐saline wastewater by traditional methods. In this study, a simple synthetic CuO/CeO2 photocatalyst is used to achieve high efficiency photodegradation of methylene blue in high salt wastewater. The p‐type CuO/n‐type CeO2 heterojunction photocatalyst is synthesized by a modified hydrothermal‐calcination method. The XRD and XPS reveal the successful synthesis of CuO/CeO2 composite. The SEM and TEM images show that the sample consists of large amounts of well‐dispersed CuO nanosphere loading on the CeO2 layers. DRS exhibits the absorption band (about 510 nm) and the band gap energy (2.43 eV) of the CuO/CeO2 composite. Compared with pure CuO, CeO2, and TiO2 (P25), the prepared CuO/CeO2 can increase the mineralization rate of MB by 18.19%~33.74%. More than 80% of MB can be effectively removed in the wastewater containing 5~80 g/L NaCl with a wide pH value range of 2.11~9.02, and the degradation processes follow the pseudofirst‐order reaction kinetics. Active species trapping experiments confirm that the degradation of methylene blue is mainly attributed to hydroxyl radical; besides, O2?? and hole (h+) also play important roles. Chlorine ions have dual effects in photocatalytic reactions. This work could provide a new approach to construct new heterojunction photocatalysts and a deeper insight for the treatment of hypersaline dye wastewater.
关键词： methylene blue,dye wastewater,hypersaline,UV/H2O2,CuO/CeO2,photocatalysis
更新于2025-09-10 09:29:36
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Removal of Carbofuran in aqueous solution by using UV-irradiation/hydrogen peroxide
摘要： Pesticide residues in natural water are one of the biggest environmental problems. carbofuran is an insecticide widely used in agricultural activities and it is easily biodegradable. Although this compound has a relatively short lifetime in soils and its persistence in the environment varies from one to several weeks. For this reason, the elimination of carbofuran residual from contaminated waters using suitable technique is of environmental interest. The aim of this study to investigate the synergetic effect of UV and UV with hydrogen peroxide on the degradation of carbofuran in aqueous solution. 50 mgL-1 aqueous solutions of carbofuran (CBF) were prepared. The solutions were exposed to various UV irradiation times. The irradiation time varied from (15-240 min). Hydrogen peroxide was set at 4.8 mM as a minimum concentration level. To follow the degradation percent, formaldehyde concentration, and to identify the intermediates by-products, GC-MS, IC, and UV-Visible spectrophotometer were used. The pH, total acidity, and dissolved oxygen values were determined before and after treatment with UV irradiation with/without hydrogen peroxide. Depending on the results obtained the mechanism pathway (degradation) was suggested. The complete removal of carbofuran in aqueous solution took place at 180 min in the presence of H2O2.
关键词： advanced oxidation processes (AOP’s),hydrogen peroxide effect,Carbofuran,UV/H2O2
更新于2025-09-10 09:29:36
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Precise Micropatterning of a Porous Poly(Ionic Liquid) via Maskless Photolithography for High-Performance Non-Enzymatic H2O2 Sensing
摘要： Porous poly(ionic liquid)s (PILs) recently have been actively serving as a multifunctional, interdisciplinary materials platform in quite a few research areas, including separation, catalysis, actuator, sensor, and energy storage, just to name a few. In this context, the capability to photo-pattern PIL microstructures in a porous state on a substrate is still missing but is a crucial step for their real industrial usage. Here, we developed a method for in situ rapid patterning of porous PIL microstructures via a maskless photolithography approach coupled with a simple electrostatic complexation treatment. This breakthrough enables designs of miniaturized sensors. As exemplified in this work, upon loading Pt nanoparticles into porous PIL microstructures, the hybrid sensor showed outstanding performance, bearing both a high sensitivity and a wide detection range.
关键词： nanoparticles,maskless photolithography,poly(ionic liquid),H2O2 sensors,porous microstructures
更新于2025-09-10 09:29:36