Combining adsorption and photocatalysis as a synergistic technique has become a research trend since adsorption is a prerequisite for photocatalytic surface reactions. In this study, a Z-scheme heterojunction FeTiO 3 @Ag/Ag 2 O with local surface plasmon resonance (LSPR) effect was fabricated for the removal of dimethoate from water. Under visible light irradiation, dimethoate could be completely removed within 75 min in the presence of 0.3 g/L FeTiO 3 @Ag/Ag 2 O (with Ag 2 O percentage of 10 wt%). High removal efficiency of dimethoate was mainly attributed to the synergistic effect between the large specific surface area of the catalyst (160.695 m 2 /g), the formation of heterojunction of FeTiO 3 and Ag 2 O, and the LSPR effect of metal Ag, which reinforced the absorption of visible light and promoted the separation and transfer of the carriers. Radicals of O 2 − and OH were the main reactive groups triggered the photocatalytic degradation process of dimethoate. Density Functional Theory (DFT) calculations indicate that P S and P–S bonds in the dimethoate molecule were more susceptible to be attacked by reactive groups. The degradation pathways mainly include oxidation of P S bond and cleavage of P–S bond, and the toxicity of most intermediates was reduced when compared with the parent compound. This study exploited the role of adsorption and photocatalysis in the field of pollutant removal, and provides ideas for the preparation of bifunctional photocatalysts.
Lithium-ion batteries (LIBs) provide many benefits, but trace electrolyte leakage can cause serious safety risks such as thermal runaway. Although gas sensors offer a potential solution, the complexity of electrolyte solvents in LIBs makes it challenging to develop sensing materials capable of universally detecting multiple solvent molecules. Here, Ag@Ag2O-functionalized SnO2 nanoflowers were synthesized using a self-template pyrolysis strategy for the sensitive detection of both common solvent molecules and widely used electrolytes. These sensors, enhanced by abundant oxygen vacancies introduced by Ag@Ag2O functionalization, exhibit excellent sensitivity, particularly to dimethyl carbonate, with a response of 106–100 ppm, a low detection limit of 11.76 ppb, and rapid response/recovery times (28/55 s) at an operating temperature of 200 °C. The sensor performance was validated by density functional theory calculations, which corroborated the effectiveness of the sensing material. In simulated LIB leakage scenarios, such as puncture and electrolyte injection, the sensors demonstrated quick responses to various common electrolyte compositions, indicating their potential for practical applications. This study highlights an effective method for fabricating composite sensing materials and emphasizes the practical significance of our universal detection approach for practical monitoring of electrolyte leakage in energy storage devices.
Ahsan Nazir,Ameena Tur Rasool,Pengwei Huo,Muhammad Saqaf Jagirani
This research used a facile chemical precipitation-photoreduction technique to fabricate a plasmonic p-n heterojunction Ag@Ag 2 O-PbBiO 2 Br (A@AO-PB) photocatalysts. The resulting materials were evaluated using various characterization techniques. Levofloxacin (LEV; 100 ml, 20 mg/l) and tetracycline (TC; 100 ml, 20 mg/l) were successfully photodegraded by the optimized 10 min-A@AO-PB (50 mg) in 120 min under visible light, with efficient degradation rates of 80.6 % and 87.0 %, respectively. The increased absorption of visible light by local surface plasmon resonance (LSPR) of plasmonic Ag and the effective separation and transfer of photogenerated carriers could be the reasons for the increase in efficiency of A@AO-PB. Transient photocurrent response (TRP), electrochemical impedance spectroscopy (EIS), and photoluminescence (PL) studies have all confirmed that 10 min-A@AO-PB effectively separates and transfers photogenerated carriers. In addition, scavenger studies have shown that the dominant active species that participated in the removal of LEV and TC are h + and •O 2 − . To find intermediates, the potential photodegradation pathways of LEV and TC were also investigated through HPLC-MS. Thus, this work describes a new photocatalyst design and a desirable plasmonic photocatalyst with p-n heterojunction that can effectively degrade LEV and TC antibiotics when exposed to visible light.