Ultrathin hydrogen-substituted graphdiyne nanosheets containing pdclusters used for the degradation of environmental pollutants

With the rapid development of industry, agriculture, and urbanization, various organic pollutants have accumulated in natural water, posing a potential threat to both the ecological environment and human beings, and removing organic pollutants from water is an urgent priority. Piezoelectric techniques, with the advantages of green, simple operation, and high efficiency, are highly sought after in the degradation of environmental organic pollutants. Moreover, combining piezoelectric techniques with advanced oxidation processes (AOPs), photocatalysis, or electrocatalysis can further effectively promote the efficient degradation of target pollutants. Therefore, a perspective is presented on the recent progress of piezoelectric techniques for the degradation of various organic pollutants from aqueous solutions. The classification of various piezoelectric materials, as well as modification strategies for improving piezocatalysis, are first systematically summarized. Furthermore, the latest research on piezocatalysis and its combination with other technologies, such as AOPs, photocatalysis, and electrocatalysis, in the degradation of environmental pollutants is discussed. The potential mechanisms of piezocatalysis are also analyzed in depth. Finally, the urgent challenges and future opportunities for piezoelectric techniques in the degradation of organic pollutants are provided.

The humans are leading a good life due to industrialization by utilizing the available natural resources such as fossil fuels, water, etc. The development of many new chemicals such as fertilizers helped to increase the food production; pesticides and herbicides in reducing the diseases, pests, and weeds in agriculture; and antibiotics in improving the life span of humans. At the same time, the wastes that are generated due to industrialization have led to environmental pollution (air, water, and soil pollution). The degradation of the pollutants is considered as a major task in reducing the environmental pollution. Microbial remediation is an alternative, natural, and cost-effective method of bioremediation for mitigating the environmental pollution. Bioremediation is a process of utilizing the live microorganisms (microbial remediation) and plants (phytoremediation) which degrade/convert the toxic pollutants into non-toxic compounds. This chapter reviews the microbial remediation, i.e., degradation of environmental pollutants by microorganisms, and mechanism and advantages of microbial remediation.

Design and synthesis of highly effective, hollow, erythrocyte-like g-C3N4 photocatalysts towards the degradation of environmental pollutants.

Review: 55 refs.

Porous framework materials for singlet oxygen generation

This review summarizes the utilization of supported noble metal nanoparticles (such as Au/TiO2, Au/ZrO2, Ag/AgCl) as efficient photo/sono-catalysts for the selective synthesis of chemicals and degradation of environmental pollutants. Supported noble metal nanoparticles could efficiently catalyze the conversion of solar energy into chemical energy. Under UV/visible light irradiation, important chemical transformations such as the oxidation of alcohols to carbonyl compounds, the oxidation of thiol to disulfide, the oxidation of benzene to phenol, and the reduction of nitroaromatic compounds to form aromatic azo compounds, are effectively achieved by supported noble metal nanoparticles. Under ultrasound irradiation, supported noble metal nanoparticles could efficiently catalyze the production of hydrogen from water. Moreover, various pollutants, including aldehydes, alcohols, acids, phenolic compounds, and dyes, can be effectively decomposed over supported noble metal nanoparticles under UV/visible light irradiation. Under ultrasound irradiation, pollutant molecules can also be completely degraded with supported noble metal nanoparticles as catalysts.

Chapter 15 - Advancement and modification in photoreactor used for degradation processes

Persistent Organic Pollutants (POPs) enter into the environment through various anthropogenic activities and cause air, water and soil pollution depending on their persistence in different matrices. POPs present in all the segments of environment are inherently toxic and accumulate in food products by atmospheric deposition from air, translocation in plants through contaminated soils and in seafood through polluted water. Moreover, the food products also get contaminated with POPs during the cooking processes including grilling and roasting. POPs settle down on soil and water surface through atmospheric fallout from air. The degradation of environmental pollutants has been achieved by different techniques such as photocatalysis and biodegradation. The separation and identification of degraded products as well as metabolites have been done preferably using liquid chromatographic techniques. Various pathways of degradation have also been suggested for degradation of different environmental pollutants. The review focuses on the application of latest chromatographic techniques for separation and identification of different degradation products of persistent organic pollutants and recent advancement in the areas of POPs analysis using liquid chromatographic techniques.

Enhanced degradation of organic pollutants over Cu-doped LaAlO3 perovskite through heterogeneous Fenton-like reactions

Nanotechnology is the science of nanoparticles, particles with dimensions of 10−9 m. Due to its huge surface area-to-mass ratio, nanoparticles exhibit excellent properties, and can be applied in many important fields such as catalytic industrial processes, biomedicine, energy production and storage, electronics, and environmental pollution control. The environmental pollution prevention can be achieved by remediation or pollutants’ degradation or sensing. This chapter will focus on the nanotechnological approach for pollution control via degradation of pollutants. Degradation of harmful organic pollutants is a chemical, physical, or a biological break of a complex pollutant structure to simpler non-or-less hazard components. Nanomaterials can act as efficient sorbents and powerful chemical/photochemical catalysts for degradation of such dangerous pollutants in wastewater and environment through accelerating the degradation rate by reducing the energy required for it and, therefore, preventing or minimizing the released pollutants. Nanometallic oxides, such as nanoiron oxide, nanotitania, and their composites, are the most common examples for the nanosorbents/catalysts used for the degradation process. In this chapter, an updated survey concerning the physical adsorption and chemical/photochemical degradation of organic compounds by using nanosimple or mixed oxides and their composites will be presented.

Heavy industrialization, specifically in the developing countries, has generated several unwanted environmental pollution. A variety of toxic organic compounds is produced in chemical and petroleum industries, which have resulted in collectively hazardous effects on the environment that needs immediate attention for remediation. Degradation of these pollutants has been tried through the various mechanism, out of which photocatalytic degradation seems to be one of the most promising approaches to reduce environmental pollution specifically in waste water treatment. Photocatalytic degradation has potential for the effective decomposition of organic pollutants due to efficiency to convert light energy into chemical energy. Additionally, the photocatalytic oxidation process is an advanced technique as it offers high degradation and effective mineralization at moderate temperature and specific radiation wavelength. Among various known photocatalysts, TiO2 is regarded as the one of the potential photocatalysts because of its hydrophilic property, high reactivity, reduced toxicity, chemical stability and lower costs. Therefore, the present chapter focuses on the role of TiO2 as the photocatalyst for the degradation of organic pollutants. The general mechanism of degradation of organic pollutants along with properties of TiO2 as the photocatalyst, existing mechanism of degradation via TiO2 was explained. The possible approaches to enhance degradation via TiO2 nanoparticle along with existing bottlenecks have been also discussed.

Research status and progress in degradation of organic pollutants via hydrogen evolution reaction and oxygen evolution reaction in wastewater electrochemical treatment

Rationally designed MoS2/protonated g-C3N4 nanosheet composites as photocatalysts with an excellent synergistic effect toward photocatalytic degradation of organic pollutants

Plasmonics for environmental remediation and pollutant degradation

Nitric oxide (NOx, including NO and NO2) is one of the most dangerous environmental toxins and pollutants, which mainly originates from vehicle exhaust and industrial emission. The development of sensitive NOx gas sensors is quite urgent for human health and the environment. Up to now, it still remains a great challenge to develop a NOx gas sensor, which can satisfy multiple application demands for sensing performance (such as high response, low detection temperature, and limit). In this work, ultrathin In2O3 nanosheets with uniform mesopores were successfully synthesized through a facile two-step synthetic method. This is a success due to not only the formation of two-dimensional (2D) nanosheets with an ultrathin thickness of 3.7 nm based on a nonlayered compound but also the template-free construction of uniform mesopores in ultrathin nanosheets. The sensors based on the as-obtained mesoporous In2O3 ultrathin nanosheets exhibit an ultrahigh response (Rg/Ra = 213) and a short response time (ca. 4 s) toward 10 ppm NOx, and a quite low detection limit (10 ppb NOx) under a relatively low operating temperature (120 °C), which well satisfies multiple application demands. The excellent sensing performance should be mainly attributed to the unique structural advantages of mesopores and 2D ultrathin nanosheets.