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Burning lignocellulosic biomass wastes in an outdoor atmosphere has placed heavy burden on ecological environment and increased risk on human health. Converting solid agricultural wastes into functional materials is a research hotspot. In this study, N-doped and CoO-loaded carbocatalyst (CoO-N/BC) was successfully synthesized from the cotton stalk biomass via a simple synthesis process of impregnation and carbonization. Compared with cotton stalk biomass derived pristine biochar, the CoO-N/BC possessed a higher specific surface area (466.631 m2 g-1 vs 286.684 m2 g-1) as well as a better catalytic performance in the activation of peroxymonosulfate (PMS) for CIP degradation. The superior catalytic efficiency was ascribed to the directional flow of electrons on the well-organized carbon network of CoO-N/BC, which accelerated electron migration and improved electron conduction ability. Based on the results of radical quenching experiment and electron paramagnetic resonance (EPR), both radical and non-radical process conjointly led to the stepwise decomposition of CIP, and singlet oxygen (1O2) mediated non-radical pathway was discovered to play a dominant role. Besides, the carbon-bridge mediated non-radical pathway was proved to accelerate this degradation process through the experiments of prolong the time of adding CIP at different time intervals. Nitrogen doped sites and CoO active sites as well as defects formed in sp2-hybridized carbon network were supposed to be the active sites for PMS. Furthermore, EIS and LSV were employed to confirm the electron transfer mediated non-radical process of reaction system. This work provides a modified strategy for the disposition of lignocellulosic biomass wastes and illuminates the underlying mechanism of heterogeneous catalysis by CoO-N/BC.

In this study, visible light (VL) was adopted for permanganate (PM) activation without additional catalyst, where sulfamethazine (SMT) was selected as the probe compound. Experiment results showed that the VL/PM system can effectively degrade SMT through pseudo-first-order reaction kinetics. Influencing factors including PM dosage, solution pH, humid acid (HA) and coexisting anions (CO32-, SO42-, Cl- and NO3-) which affect SMT photo-degradation were also examined. Pyrophosphate (PP) had an inhibitory effect on SMT degradation due to the complexation of PP with Mn (III). Electron spin resonance (ESR) spectrometry and UV-Vis spectrophotometer proved that VL can activate PM to generate ·O2- and Mn (III) reactive species. Furthermore, based on the active site prediction, intermediates identification and Density Functional Theory (DFT) calculation, two main degradation pathways involving SMT molecular rearrangement and cleavage of S-N bond were proposed. Moreover, the energy barriers of the two degradation pathways were also calculated. This study offers a novel approach for aqueous SMT removal and deepens our understanding of the degradation mechanism of SMT through DFT calculation, which hopes to shed light on the future development of VL/PM treatment.

Pharmaceuticals and personal care products (PPCPs) are a large class of emerging contaminants. Here, we develop a 2D/2D Mo2C/g-C3N4 Van der Waals (VDW) heterojunction photocatalyst for typical PPCPs degradation. The 2D Mo2C shows unique electronic transport properties and allows the integration with other 2D materials for fabricating intriguing 2D interface. The Mo2C strongly coordinates with g-C3N4 to endow the ordered in-plane electron migration in g-C3N4 nanosheets and the VDW forces induce the electrons transfer within interlayers, building an internal electric field and stimulating the photogenerated charge kinetics. In addition, Mo2C can ameliorate the light absorption capacity and trap electrons to elongate the lifetimes of charge carriers. This synergy between VDW heterojunction and 2D structure engineering contributes to the superior photocatalytic activity for tetracycline degradation. Advanced characterizations, charge density based on density function theory calculations and the absence of charge transfer between layers confirm the VDW interactions between the individual components. This work provides a highly efficient and green strategy for typical PPCPs removal, and sheds lights on the construction of 2D/2D VDW heterojunction photocatalysts.

Bismuth tungstate (Bi2WO6) was well known for its low price, nontoxicity and stability in the removal of organic pollutions. However, poor visible light absorption and fast carrier recombination led to its moderate activity. Therefore, a Z-scheme photocatalyst constructed by Bi2WO6 nanosheets, graphene oxide (GO) and silver bromide (AgBr) nanoparticles was successfully prepared. Previous reports suggested that Z-scheme structure based on Bi2WO6 nanosheets could obtain more active sites. And characterization results clarified that the addition of AgBr brought broadened visible light response range, inducing more photocarrier generation. Meanwhile, the optimized Z-scheme composite 15%AgBr/5GO/Bi2WO6 (15A/5G/BW) possessed accelerated interfacial charge separation and transfer, which was resulted from excellent electron conductivity in GO. As a result, 15A/5G/BW exhibited superior photocatalytic activities for tetracycline hydrochloride (TC). The highest degradation efficiency could reach 84% under visible light illumination, and the kinetic constant was 0.0515 min−1 which was approximately 4.60 and 3.16 times higher than that of AgBr and Bi2WO6, respectively. Furthermore, liquid chromatography-mass spectrometry (LC-MS) and trapping experiments revealed possible TC degradation pathways and main active radicals during photocatalysis process. A facial strategy for rational design of ternary photocatalyst towards the degradation of refractory antibiotics was proposed.

Pyrogenic carbonaceous materials (PCM) with diverse surface functionalities are recently described as efficient, heterogeneous, nonmetallic mediators or catalysts, and show excellent performances in the degradation of organic contaminants. Herein, surface functionalities considered to be responsible for the reactivity of PCM are overviewed. It is shown that chemical surface functionalities of PCM can mediate the production of reactive species from oxygen, peroxides, persulfate, ozone for contaminants elimination, including oxygen functionalities, nitrogen functionalities, sulfur functionalities, and persistent free radicals. The possible generation processes of various reactive species promoted or inhibited by surface functionalities and the underlying reaction mechanisms of the further organic transformations are also summarized. The reaction mechanisms of electron transfer, addition and hydrogen abstraction are established. Furthermore, the applications of PCM mediators in aquatic environment, soil and atmosphere are presented to highlight the bright application prospects, and future prospects for the organic contaminant degradation mediated via PCM are proposed.

The growing concerns over the environmental toxicity of sulfonamides (SNs) require immediate action to establish efficient and sustainable processes to address this issue. Adsorption, photodegradation and Fenton/Fenton-like reactions are the most applied processes to remove SNs. However, the adsorption behavior, degradation mechanisms and toxicity of intermediates need further investigation to guide engineering applications. The review focuses on the recent progress and challenges on adsorption, photodegradation and Fenton/Fenton-like techniques for SNs removal. In addition, influences of solution pH and matrix components on adsorption mechanisms are discussed. In particular, the degradation pathway of SNs and toxicity assessment of their intermediates are also analyzed. Finally, conclusions and research gaps in this field are briefly proposed. Publications on this topic have grown exponentially over the last decade. This review provides a unique and comprehensive environmental perspective, as well as the latest knowledge on SNs adsorption and reactive removal by different technologies.

Since the global energy demand and consumption increased sharply, photocatalytic water splitting becomes a promising solution to provide continuous and sustainable energy resources. However, exploring photocatalysts that could meet energy needs and put into industrial manufacture remains a challenging task. Metal-organic frameworks (MOFs), as a class of porous crystalline materials with tailorable structure and ultrahigh surface area, are regarded as an ideal candidate for photocatalysis application. Recently, their peculiar employment in photocatalytic water splitting aroused tremendous interests. Although this topic still in early stage, recent advanced experiments results have certified its potential for future application. This review starts with the fundamentals of photocatalytic water splitting, and subsequently summarizes and exemplifies recent developments of MOFs based- and derived-photocatalysts for water splitting, including water-splitting half reaction and overall water splitting. Particularly, two strategies to enhance photocatalytic performance of MOFs are specific emphasized, namely functional modification and surface or pore decoration. Finally, this review identifies the scarcities of MOFs based- and derived-photocatalysts and proposes pertinent suggestions for further improvement, whilst highlights a green future for photocatalytic water splitting.

Objective. To discuss the effect of systematic follow-up home visits on the healthy behavior of patients after interventional treatment of arteriosclerosis obliterans (ASO). Methods. A total of 100 patients discharged from hospital after the interventional treatment of ASO were randomly divided into an observation group and a control group, each group having 50 members. The members of each group were given professional discharge instructions; the control group received follow-up telephone calls, while the observation group had systematic follow-up home visits which were recorded in detail; a comparison and an analysis of the healthy behaviors of the members in the two groups were made after one year of follow-up. Results. The healthy behavior of the observation group members was obviously better than that of the control group members. (There were significant differences in life attitudes, disease knowledge, awareness of risk factors, enthusiasm for exercise, and timely medicine use) The X2 values ...