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With PhI as catalyst and mCPBA as oxidant, a novel and efficient catalytic procedure has been developed for the acetoxyselenylation and formyloxyselenylation of alkenes. In this protocol, PhI is first oxidized into hypervalent iodine intermediate, which promotes the cleavage of Se-Se bond in diselenides. The in situ generated electrophilic selenium species then reacts with alkenes, affording 2-acetoxy-1-selenides and 2-formyloxy-1-selenides in high regioselectivity and good yields. [ABSTRACT FROM AUTHOR]

Using potassium iodide as a catalyst andm-chloroperbenzoic acid as an oxidant, an efficient catalytic procedure has been developed for the azidoselenenylation of alkenes with sodium azide and diselenides, and a series of corresponding β-azidoselenides, most of which are new compounds, have been prepared in moderate to good yields under mild reaction conditions. This in situ generation of the electrophilic selenenylating reagents with addition to alkenes is a stereospecificantiaddition, which occurs with a Markovnikov orientation. [ABSTRACT FROM AUTHOR]

In the presence of NH4I as catalyst and m-chloroperbenzoic acid as oxidant, the Se-Se bond cleavage of diselenides undergoes smoothly. The in situ generated reactive electrophilic Se species reacts with alkenes quickly, and a series of β-hydroxy selenides are prepared in good yields. This new catalytic method for synthesis of β-hydroxy selenides is a stereospecific anti addition, which occurs with a Markovnikov orientation. [ABSTRACT FROM AUTHOR]

For the low concentration and intractable VOCs and CO 2 , plasma-coupled catalysis has superior advantages and development potential to deal with them. However, there are critical issues such as efficiency to be further improved and unclear coupling mechanism to reveal. In this review, various types of catalysts are categorized and evaluated by exploring their enhancement effect in plasma-catalytic system to indicate their synergistic excellence and application limitation. Besides, the detailed research of synergistic mechanism between plasma and catalysis is given more attention, which is rapidly progressing due to the development of in-situ experimental techniques and kinetic analysis approach. In our view, the future direction of plasma catalysis is to reveal the synergistic mechanism more deeply for efficiency improvement with efficient catalysts, and pave the way for practical application. [Display omitted] • The theoretical basis of plasma-coupled catalytic conversion of VOCs and CO 2 was introduced. • Enhancement of conversion efficiency by classified catalysts was discussed and evaluated. • Recent advances in in-situ experiments to investigate the synergistic mechanism were reviewed. • Prospects and challenges of plasma-coupled catalysis in VOCs removal and CO 2 conversion were pointed out. [ABSTRACT FROM AUTHOR]

• CO 3 2− enhanced catalytic activity and stability of Co 3 O 4 for PMS activation. • Faster catalysis occurred when solution pH exceeded but approached pH PZC of Co 3 O 4. • The dominated reactive species switched from •OH/SO 4 •− to 1O 2 after adding CO 3 2-. • CO 3 2− drove the catalytically active center migrating from Co(II) to Co(III). • Co(III) and CO 3 2−/OH- were electron and proton acceptors to promote 1O 2 evolution. Transition-metal catalysts (TMCs) for peroxymonosulfate (PMS) activation suffer from low stability (i.e. severe metal leakage and poor reusability) when maintaining high activity in water decontamination. An innovative carbonate (CO 3 2−)-mediated method to synchronously enhance the catalytic activity and stability of TMCs was developed herein. In a model PMS/Co 3 O 4 nanowire system for bisphenol A (BPA) degradation, the first-order kinetic constant and total organic carbon removal ratio were increased by 202.27% and 71.32% upon adding CO 3 2−, respectively. Meanwhile, the cobalt release amount was significantly reduced from 4.90 to 0.03 mg/L, and the number of reuse with high efficiency (>90% of BPA removal within 10 min) was augmented from 1 to 3 times. The CO 3 2− buffered pH decline to repress metal leakage, and promoted Co(III) reduction into Co(II) to avoid the over-oxidation of catalyst. Under the driving of CO 3 2−, the dominated reactive species were switched from •OH/SO 4 •- to 1O 2 accompanying the migration of catalytic center from Co(II) to Co(III). The Co(III) and CO 3 2−/OH- acted as electron and proton acceptors, respectively, to accelerate PMS decomposition into SO 5 •- and subsequent generation of vast 1O 2. This work proposes a green way to construct novel 1O 2 -based catalytic systems with excellent activity and stability for pollution remediation. [ABSTRACT FROM AUTHOR]