Growth of Ag/g-C_(3)N_(4) nanocomposites on nickel foam to enhance photocatalytic degradation of formaldehyde under visible light

Formaldehyde is a pollutant that significantly affects the indoor air quality.However,conventional remediation approaches can be challenging to deal with low-concentration formaldehyde in an indoor environment.In this study,Photocatalysts of Ag/graphitic carbon nitride(g-C_(3)N_(4))/Ni with 3D reticulated coral structure were prepared by thermal polymerization and liquid phase photo-deposition,using nickel foam(NF)as the carrier.Experiments demonstrated that when the Ag concentration was 3%,and the relative humidity was 60%,the Ni/Ag/g-C_(3)N_(4)showed the maximum degradation rate of formaldehyde at 90.19%under visible light irradiation,and the formaldehyde concentration after degradation was lower than the Hygienic standard stated by the Chinese Government.The porous structure of Ni/Ag/g-C_(3)N_(4)and the formation of Schottky junctions promoted the Adsorption efficiency and degradation of formaldehyde,while the nickel foam carrier effectively promoted the desorption of degradation products.Meanwhile,the degradation rate was only reduced by3.4%after 16 recycles,the three-dimensional porous structure extended the lifetime of the photocatalyst.This study provides a new strategy for the degradation of indoor formaldehyde at low concentrations.

Natural siderite derivatives activated peroxydisulfate toward oxidation of organic contaminant: A green soil remediation strategy

Natural siderite(FeCO_(3)),simulated synthetic siderite and nZVI/FeCO_(3) composite were used as green and easily available iron-based catalysts in peroxydisulfate activation for remediating 2-chlorophenol as the target contaminant and this technique can effectively degrade organic pollutants in the soil.The key reaction parameters such as catalysts dosage,oxidant concentration and pH,were investigated to evaluate the catalytic performance of different materials in catalytic systems.The buffering property of natural soil conduced satisfactory degradation performance in a wide pH range(3-10).Both the main non-radical of ^(1)O_(2) and free radicals of SO_(4)^(-) and OH·were evidenced by quenching experiment and electron paramagnetic resonance.The reduction of nZVI on FFC surface not only has the advantage for electronic transfer to promote the circulation of Fe(Ⅲ)to Fe(Ⅱ),but also can directly dechlorinate.Furthermore,the intermediates were comprehensively analyzed by GC-MS and a potential removal mechanism of three oxidant system for 2-CP soil degradation was obtained.Briefly,this research provides a new perspective for organic contaminate soil treatment using natural siderite or simulated synthetic siderite as efficient and environmental catalytic material.