As a fascinating conjugated polymer, graphitic carbon nitride (g-C3N4) has become a new research hotspot and drawn broad interdisciplinary attention as a metal-free and visible-light-responsive photocatalyst in the arena of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability, and “earth-abundant” nature. This critical review summarizes a panorama of the latest progress related to the design and construction of pristine g-C3N4 and g-C3N4-based nanocomposites, including (1) nanoarchitecture design of bare g-C3N4, such as hard and soft templating approaches, supramolecular preorganization assembly, exfoliation, and template-free synthesis routes, (2) functionalization of g-C3N4 at an atomic level (elemental doping) and molecular level (copolymerization), and (3) modification of g-C3N4 with well-matched energy levels of another semiconductor or a metal as a cocatalyst to form heterojunction nanostructures. The constructi...

Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability?

There is a special reason for reviewing this book at this time: it is the 50th edition of a compendium that is known and used frequently in most chemical and physical laboratories in many parts of the world. Surely, a publication that has been published for 56 years, withstanding the vagaries of science in this century, must have had something to offer. There is another reason: while the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice). I believe that the Handbook can be useful in those laboratories. One of the reasons, among others, is that the various basic items of information it offers may be helpful in new tests, either physical or chemical, which are continuously being published. The basic information may relate

Handbook of Chemistry and Physics

Sulfate radical-based advanced oxidation processes (SR-AOPs) employing heterogeneous catalysts to generate sulfate radical (SO4 −) from peroxymonosulfate (PMS) and persulfate (PS) have been extensively employed for organic contaminant removal in water. This article aims to provide a state–of–the–art review on the recent development in heterogeneous catalysts including single metal, mixed metal, and nonmetal carbon catalysts for organic contaminants removal, with particular focus on PMS activation. The hybrid heterogeneous catalyst/PMS systems integrated with other advanced oxidation technologies is also discussed. Several strategies for the identification of principal reactive radicals in SO4 −–oxidation systems are evaluated, namely (i) use of chemical probe or spin trapping agent coupled with analytical tools, and (ii) competitive kinetic approach using selective radical scavengers. The main challenges and mitigation strategies pertinent to the SR-AOPs are identified, which include (i) possible formation of oxyanions and disinfection byproducts, and (ii) dealing with sulfate produced and residual PMS. Potential future applications and research direction of SR-AOPs are proposed. These include (i) novel reactor design for heterogeneous catalytic system based on batch or continuous flow (e.g. completely mixed or plug flow) reactor configuration with catalyst recovery, and (ii) catalytic ceramic membrane incorporating SR-AOPs.

Generation of sulfate radical through heterogeneous catalysis for organic contaminants removal: Current development, challenges and prospects

Application of peroxymonosulfate and its activation methods for degradation of environmental organic pollutants: Review

Review of iron-free Fenton-like systems for activating H2O2 in advanced oxidation processes

Catalytic activation of peroxymonosulfate (PMS) to generate radicals has received considerable and increasing attention in environmental catalysis field. The development of highly efficient and environmentally friendly oxidation processes has been one of the most important and greatly challenging goals in PMS activation field. Herein, an effective and stable catalyst (ACFs-CoPc) was proposed for PMS activation by supporting cobalt phthalocyanine (CoPc) onto activated carbon fibers (ACFs) covalently. With the dye of Acid Red 1 (AR1) as probe compound, ACFs-CoPc could effectively activate PMS to eliminate AR1, and the catalytic activity of ACFs-CoPc was almost not impaired during ten successive runs without detectable cobalt leaching, indicating that ACFs-CoPc/PMS system was a pro-environmental and efficient oxidation system. A hybrid method that combines electron paramagnetic resonance (EPR) technology with different radical scavengers effect on PMS activation was employed for the investigation of active species during the catalytic reaction. It was found that both hydroxyl and sulfate radical (OH, SO4−) were generated; importantly, SO4− was speculated to serve as the dominant active species in the catalytic oxidation of AR1. Based on these results, a possible mechanism was proposed.

Novel green activation processes and mechanism of peroxymonosulfate based on supported cobalt phthalocyanine catalyst

A novel metallophthalocyanine derivative, cobalt tetra (2,4-dichloro-1,3,5-triazine) aminophthalocyanine (Co-TDTAPc), was prepared and immobilized on cellulosic fiber by covalent bond to obtain a supported oxidation catalyst (Co-TDTAPc-F). Co-TDTAPc-F/H2O2 system based on phase-transfer catalytic oxidation for decomposing dyes, including acid, reactive, and direct dyes, has been investigated thoroughly. Compared to traditional adsorption technologies and advanced oxidation processes (AOPs) for dye treatment, Co-TDTAPc-F/H2O2 combines the advantages of both and is more efficient and more effective. Azo dyes such as C. I. Acid Red 1 (AR1) can be quickly adsorbed onto/into the fiber from aqueous solution and decomposed in situ simultaneously in the presence of Co-TDTAPc-F and H2O2. It has been found that the reaction process is not affected by the visible light. Furthermore, it turns the negative effect of NaCl normally observed in homogeneous catalysis into positive one. The catalytic reaction can proceed a...

Highly efficient decomposition of organic dyes by aqueous-fiber phase transfer and in situ catalytic oxidation using fiber-supported cobalt phthalocyanine.

Visible light-responsive photocatalysis has shown great potential for effluent treatment as an environmentally friendly method. Herein, the photocatalyst of graphitic carbon nitride (g-C3N4) coupled with zinc phthalocyanine (g-C3N4/ZnTcPc) was prepared by immobilizing zinc tetracarboxyphthalocyanine (ZnTcPc) onto g-C3N4 covalently. The spectral response region of g-C3N4 has been extended from 450 nm to more than 800 nm sensitized by ZnTcPc, which is well known for the red/near-IR (Q band) light absorption. Compared with pure g-C3N4 and ZnTcPc, g-C3N4/ZnTcPc presented a significantly enhanced photocatalytic activity for the degradation of rhodamine B (RhB) and 4-chlorophenol (4-CP) under visible irradiation. The photocatalytic activity of g-C3N4 has been improved by the coupled interaction with ZnTcPc over a wide pH range. Moreover, besides photogenerated hole, the presence of singlet oxygen (1O2), superoxide radical ( O2−) and hydroxyl radical ( OH) has been evidenced in the visible light-responsive catalytic system with g-C3N4/ZnTcPc, especially in alkaline condition. The possible photocatalytic degradation pathway of RhB has been proposed according to the results of ultra-performance liquid chromatography and high-definition mass spectrometry (UPLC Synapt G2-S HDMS). This synergistic photocatalytic process will provide useful insights to make full use of solar light for future application to eliminate recalcitrant organic pollutants.

Synergistic photocatalytic properties and mechanism of g-C3N4 coupled with zinc phthalocyanine catalyst under visible light irradiation

Efficient removal of dyes using heterogeneous Fenton catalysts based on activated carbon fibers with enhanced activity

https://www.rsc.org/suppdata/GC/b9/b917233e/b917233e.pdf

Wenxing Chen

Papers

Novel green activation processes and mechanism of peroxymonosulfate based on supported cobalt phthalocyanine catalyst

Highly efficient decomposition of organic dyes by aqueous-fiber phase transfer and in situ catalytic oxidation using fiber-supported cobalt phthalocyanine.

Synergistic photocatalytic properties and mechanism of g-C3N4 coupled with zinc phthalocyanine catalyst under visible light irradiation

Efficient removal of dyes using heterogeneous Fenton catalysts based on activated carbon fibers with enhanced activity

Platinum-nanoparticle-loaded bismuth oxide: an efficient plasmonic photocatalyst active under visible light