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Highlights • The ATP/polymers composites were first prepared for solar steam generation. • It possesses a high evaporation efficiency of 85% under 1 sun irradiation. • It has advantages of cost-efficient, simple and scalable manufacture process. Abstract Solar steam generation has been attracting wide attention for boosting the evolution of solar-energy-harvesting technology. Here, we demonstrate the fabrication of a novel bilayer photothermal material based on attapulgite/poly acrylamide composite (APAC), which was prepared by the solution polymerization of acrylamide (AM) in the presence of attapulgite using N, N′-Methylene bisacrylamide (MBA) as a crosslinker, for efficient solar steam generation. The APAC shows better thermal stability with a decomposition temperature of 250 °C, good mechanical property with a compress strength of up to 125 KPa at 75% strain and a low apparent density (0.0191 g·cm−3) with abundant porosity accompanying with a low thermal conductivity (0.07 W m−1 K−1). To enhance the light absorption of APAC, a thin carbon layer was created on the surface of APAC via a facile flame treatment. Under our conditions, the bilayered APAC shows a high vapor rate of 1.2 kg m−2 h−1 under 1 sun illumination, equal to 85% solar-to-vapor efficiency. With the merits of cost-efficient, scalable manufacture, high solar energy conversion efficiency, the APAC may hold the great potential as high-performance photothermal materials for solar energy generation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Foam fluid with MQDs@SIL (0.005 wt%) showed the efficient plugging action. • The unique surface favored the adsorption of MQDs@SIL on the gas–liquid interface. • The enhanced oil recovery was 18.2% in the stage of foam fluid flooding. • MQDs@SIL provided unique recycling and reusing benefits. Nanoparticle-stabilized foam fluid provided excellent efficiency in tertiary oil recovery, and a more appealing technique is to exploit reusable low-dimensional nanomaterials, which can achieve better oil-displacement efficiency during the period of global decarbonization. Herein, the magnetic quantum dots (MQDs) were synthesized and then modified by a silane-coupling ionic liquid (SIL) to produce unique quantum dots MQDs@SIL. A series of characterizations and foaming measurements reveal that MQDs@SIL with an average surface grafting density of 1.01 functional chains nm−2 at an ultra-low concentration (0.005 wt%) demonstrated distinct foam stability and salt resistance capability, as well as a unique defoaming performance in a constant magnetic field for regulated foam performance at high temperature. The stretched-straight functional chains and adequate hydrophilic-hydrophobic surface of MQDs@SIL substantially favor the nonreversible adsorption of MQDs@SIL on the gas–liquid interface, leading to an increased surface elasticity, and thus an enhanced foam stability. MQDs@SIL-stabilized foam liquid demonstrated exceptional plugging performance and achieved an enhanced oil recovery of 18.2 % in the stage of foam fluid flooding, exceeding most nanoparticle-stabilized foam fluids ever reported. Furthermore, MQDs@SIL with the unique magnetic property provided unique recycling and reusing benefits, emphasizing their potential applications for enhanced oil recovery. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reduction of BrO 3 − by Fe(II) produced HO•, O 2 •− and reactive bromine species. • HO• and O 2 •− were generated from decomposition of BrO 3 − and its intermediates. • BrO 3 −/Fe(II) system can efficiently degrade organics with diverse structures. • Degradation products of carbamazepine were identified in BrO 3 −/Fe(II) system. • Effect of reaction conditions and water matrices was studied. Reduction of bromate (BrO 3 −) by various technologies has been extensively investigated, while the fate of oxygen and bromine atoms in BrO 3 − in these processes has been largely ignored. In this study, reduction of BrO 3 − by Fe(II) ions was investigated under various conditions via electron spin resonance (ESR), laser flash photolysis (LFP), probe of phenol and quenching experiments. It was found that reduction of BrO 3 − by Fe(II) ions produced HO•, O 2 •− and reactive bromine species (eg., Br• and Br 2 •−). HO• and O 2 •− were generated from release of one/two oxygen atoms in BrO 3 − and its reduction intermediates (BrO 2 − and BrO−) at one time, while Br• and Br 2 •− were generated from activation of hypobromous acid by Fe(II) and reactions of HO• with formed Br−. Due to the formation of these reactive species, the tested ten organic pollutants with diverse structures can be efficiently degraded, which including carbamazepine (CBZ), ibuprofen, phenol, benzoic acid, paracetamol, bisphenol a, 4-chlorophenol, oxcarbazepine, diclofenac and sulfamethoxazole. CBZ degradation intermediates by BrO 3 −/Fe(II) system were specially identified by liquid chromatography (LC)-mass spectrometry (MS), and three pathways of hydroxylation/nitrosylation, ring contraction-amine cleavage and bromination for CBZ degradation were proposed accordingly. This study might shed new fundamental insights to bromate reduction and its implication for transformation of co-existed organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reactive species in Cu-catalyzed persulfate activation are summarized. • Cu-catalyzed radical/nonradical persulfate activation pathways are elaborated. • Uncertainties on role of Cu-catalysts in persulfate activation are explicated. • Controversies over persulfate activation mechanism are discussed. Persulfate-based Advanced oxidation processes (AOPs) have gained a lot of attentions in organic decontamination in the past decades. Copper (Cu)/persulfate is an interesting coupling system due to its versatile activation pathways with formation of multiple radical and nonradical species. Thus, in the review, the generation mechanisms of various reactive species in Cu/persulfate system are analyzed and summarized. Firstly, the general activation mechanisms of Peroxydisulfate (PDS) and Peroxymonosulfate (PMS) catalyzed by Cu are summarized, and formation processes of four types of free radicals (SO 4 −, OH, SO 5 − and O 2 −) and three types of non-radicals (Cu(III), surface activated PDS/PMS and 1O 2) in the system are compared. Moreover, the role of copper ions and copper oxides in generation of these reactive species is discussed in details. Finally, the concluding remarks and perspectives for future research on Cu/persulfate AOPs are proposed. The review provides a comprehensive and deep insight into the formation and reaction mechanisms of radical and nonradical species, points out current controversies over reaction mechanisms involved in the Cu-persulfate-based AOPs, and proposes a guideline for future research and engineering application of persulfate. [ABSTRACT FROM AUTHOR]