Photocatalytic degradation of ethylene in cold storage using the nanocomposite photocatalyst MIL101(Fe)-TiO2-rGO

The visible light photocatalytic degradation of ethylene using a polyvinyl alcohol film loaded with Ag2O-TiO2-Bi2WO6 heterojunction microspheres

Active packaging containing photocatalyst is generally used to solve the issues of loss and quality deterioration of fresh fruits. However, only ultraviolet (UV) light can activate these photo-catalysts in ethylene photo-degradation. To overcome this limitation, green synthesized silver nanoparticles (AgNPs) that inhibits ethylene gas production under visible light has been developed. In this study, spent green tea was mixed with deionized water at various ratios ranging from liquid to solid to obtain spent green tea extract (ex-SGT) having different concentrations used for synthesis of AgNPs. The results indicated that a good distribution of particles with a bandgap energy of 2.17 eV which was in the visible region for ethylene photo-degradation was successfully obtained with the synthesized AgNPs-60 (ex-SGT at the ratio of 60:1). The coated paper possessed an antibacterial activity and decreased the ethylene concentration in mango’s packaging. Based on the finding in this work, it appears that the coated paper could have potential to be used for novel packaging of fruits to delay their ripening so that their freshness can be maintained.

Green synthesis of nanosilver coating on paper for ripening delay of fruits under visible light

The photocatalytic degradation of ethylene is an efficient technology applied to the fruit ripening control. When photocatalytic reactions remove ethylene from the storage and transportation environment of fruits and vegetables, the respiration rate decreases, and the quality of food is preserved for a long time. It is well known that photocatalysis involves the photogeneration of electron-hole pairs (e−/h+) under light irradiation, separation, and migration of charges on the material surface, oxidation and reduction reactions involving electrons and holes pairs, and charge recombination on the catalyst surface. In this study, we report the syntheses, characterization, and evaluation of photocatalytic activity of the β-Ag2MoO4/g-C3N4 photocatalysts to degrade ethylene in the gas phase under UV-A irradiation. The effect of the β-Ag2MoO4:g-C3N4 ratio on reactive oxygen species (ROS) generation and increasing the electron/hole charge separation is evaluated in detail. Under UV-A illumination and the absence of water, superoxide radicals are most efficiently produced in hybrid samples containing a higher g-C3N4 percentage, but lower O2·− amount is formed in pure g-C3N4. The hybrid samples containing higher amounts of g-C3N4 are more efficient to degrade ethylene because of better e− and h+ charge separation and superoxide radicals’ formation, which participate in ethylene degradation. 

Evaluation of reactive oxygen species and photocatalytic degradation of ethylene using β-Ag2MoO4/g-C3N4 composites

Plastics, due to its low cost, light weight, and tunable mechanical strength, is one of the most commonly used materials in everyday life. However, massive production of plastics within the...

State of the Art in Photochemical Degradation of (micro)Plastics: From Fundamental Principles to Catalysts and Applications

Titanium mesh-supported TiO2 nano-film for the photocatalytic degradation of ethylene under a UV-LED

Transient liquid phase (TLP) bonding is a promising solution for high temperature (HT) electronic devices as high-quality bonds can be formed at a temperature much lower than the melting point of the resulted joint. In this work, Ag-rich Ag–Sn TLP bonding was evaluated as a potential die attach solution for HT (250 °C) electronic applications. The influence of varying the Ag content on the mechanical strength of the Ag–Sn TLP joint was investigated through room temperature (RT) and HT shear tests. The study was complemented with X-ray imaging of any void formation, and scanning electron microscope (SEM)/energy-dispersive X-ray spectroscopy (EDX) spectra for composition and morphology analysis. It is shown that the Ag-rich joint comprises Ag and Ag3Sn intermetallic compound (IMC), and no obvious void was observed. The shear strengths of the joints measured at both RT and 250 °C have satisfied the requirement for HT applications. In addition, the fractured surfaces after the shear test showed that the failure of Ag-rich joints occurred mostly in the Ag3Sn IMC region. Furthermore, the shear strength improved with increasing Ag content (up to 81.5 at.%) in the bond.

Guangxu Yan

Papers

Titanium mesh-supported TiO2 nano-film for the photocatalytic degradation of ethylene under a UV-LED

Ag–Sn Transient Liquid Phase Bonding for High Temperature Electronic Packaging: Effect of Ag Content