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Chloronitrobenzenes are typical refractory aromatic halogenated nitroaromatic and high-toxic contaminants. The reduction process of chloronitrobenzenes cannot realize their mineralization, and the existence of chlorine group is detrimental to degradation through single chemical oxidation technology. Herein, the Au nanoparticles and graphitic carbon nitride co-modified TiO 2 nanotube arrays (Au/g-C 3 N 4 /TNAs) photoanodes were fabricated to degrade o -chloronitrobenzene (o -CNB) target pollutant in photoelectrocatalytic (PEC) system. The Au/g-C 3 N 4 /TNAs fabricated with 0.20 mM HAuCl 4 0.4 H 2 O (Au/g-C 3 N 4 /TNAs-0.20) had more superior optical and photoelectrochemical properties than other fabricated photoanodes. Au/g-C 3 N 4 /TNAs-0.20 photoanode increased dechlorination efficiency through reduction process, which was beneficial to o -CNB degradation and TOC removal. The coexistence of anions and humic acid inhibited the PEC degradation of o -CNB. The photogenerated electron, •O 2 −, hole and •OH participated in o -CNB degradation in PEC system. The degradation pathway of o -CNB was inferred through GC-MS spectra and DFT calculation. The acute toxicity and bioaccumulation factor of o -CNB were effectively reduced by PEC degradation. [Display omitted] • Au/g-C 3 N 4 /TNAs photoanodes were fabricated for PEC degradation of o -CNB. • The g-C 3 N 4 and Au nanoparticles improved photoelectrochemical properties of TNAs. • Au/g-C 3 N 4 /TNAs photoanode increased dechlorination and TOC removal rate of o -CNB. • Degradation pathways of o -CNB were proposed by GC-MS analysis and DFT calculation. • Overall toxicity of o -CNB was reduced after PEC degradation by Au/g-C 3 N 4 /TNA-0.20. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thiazolo[5,4- d ]thiazole (TzTz) is employed as the linkage to synthesize CMPs. • The TzTz-linked CMPs are thoroughly characterized. • TzTz-CMP-3 displays excellent photocatalytic activity for selective aerobic oxidation. • The photocatalytic properties of TzTz-linked CMPs could be tailored by molecular symmetry. • TzTz-CMP-3 with unprecedent activity is uncovered for the formation of sulfoxides. Developing selective formation of sulfoxides by aerobic oxidation of sulfides over highly efficient visible-light photocatalysts is an essential but challenging task. Herein, a conjugated microporous polymer (CMP) photocatalyst with the desired linkage thiazolo[5,4‑ d ]thiazole (TzTz) is presented to undertake this task. Remarkably, a catalyst-free solvothermal process afforded TzTz-CMP-3 from tetra(4-formylphenyl)-benzene and dithiooxamide. The photocatalytic activity of TzTz-CMP-3 is demonstrated with the blue light-powered selective formation of sulfoxides by aerobic oxidation of sulfides. A wide range of sulfoxides can be effectively formed by oxidation of sulfides with excellent product selectivities (up to 99 %) over the TzTz-CMP-3 photocatalyst. The more symmetric π-conjugated aromatic ring of TzTz-CMP-3 endows it with more favorable activity than the less symmetric ones. This work underscores the symmetry of building blocks for CMPs for selective photocatalytic formation of valuable organic molecules. [ABSTRACT FROM AUTHOR]

The selective aerobic oxidation of benzylamine by cooperative ARS-TNTs photocatalysis with TEMPO+BF 4 −. [Display omitted] • Anatase TNTs deliver outstanding photocatalytic activity. • ARS binds with TNTs through surface hydroxyl sites. • Electron transfer occurs smoothly between ARS-TNTs and TEMPO+BF 4 −. • With increased polarity, TEMPO+BF 4 − can increase cooperative photocatalysis. • Green light-driven selective aerobic oxidation of amines has been achieved. Visible light photocatalysis could offer an eco-friendly alternative for selective transformation of organic molecules. Herein, a cooperative system is created with alizarin red S (ARS), TiO 2 nanotubes (TNTs), and an extra redox mediator. The electron transfer between oxidatively quenched ARS-TNTs and the redox mediator is the key to secure cooperative photocatalysis. The selective aerobic oxidation of primary and secondary amines was constructed by cooperative photocatalysis of ARS-TNTs with 2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (TEMPO+BF 4 −) driven by green light. Specifically, the activity of anatase TNTs could reach about 2.2 times that of the P25 (Aeroxide P25) TiO 2 precursor. Due to increased polarity, TEMPO+BF 4 − serves more efficiently for electron transfer than (2,2,6,6-tetramethylpiperidin-1-yl)oxy (TEMPO), conferring above 1.5 times of activity that of TEMPO for the selective aerobic conversion of amines. This work features the potential of designing redox mediators in amplifying cooperative photocatalysis driven by visible light. [ABSTRACT FROM AUTHOR]

The nitrogen/oxygen self-doped porous biochar (NO/PBC) and NO/PBC supported CuFeO 2 (CuFeO 2 -NO/PBC) were prepared and mixed as cathode catalysts for gas diffusion electrode (GDE) fabrication. The fabricated GDE could realize H 2 O 2 electrogeneration and activate H 2 O 2 to produce active radicals through NO/PBC and CuFeO 2 , respectively. The GDE with the NO/PBC to CuFeO 2 -NO/PBC ratio of 1:1 (CuFeO 2 -NO/PBC-GDE-1.0) possessed more superior catalytic performance for tetracycline degradation in heterogeneous photo-electro-Fenton (hetero-PEF) system under visible light than other as-fabricated GDEs. The •OH was primary species, and •O 2 - was auxiliary species for hetero-PEF degradation of tetracycline through CuFeO 2 -NO/PBC-GDE-1.0. The electron on the cathode surface and photoinduced electron could accelerate Fe3+/ Fe2+ and Cu2+/ Cu+ redox cycle, promoting •OH/•O 2 - production and tetracycline degradation. The toxicity estimation of tetracycline and intermediates, TOC removal and Escherichia coli growth inhibition confirmed that the remission of overall toxicity, the inhibition of antibacterial property and the mineralization of tetracycline were achieved in hetero-PEF system. [Display omitted] • CuFeO 2 -NO/PBC was prepared by hydrothermal method using NO/PBC as a support. • CuFeO 2 -NO/PBC-GDE-1.0 was fabricated for the hetero-PEF degradation of tetracycline. • CuFeO 2 -NO/PBC-GDE-1.0 could generate and activate H 2 O 2 to produce active radicals • Cathode electron and photoinduced electron promoted regeneration of Fe2+ and Cu+. • Hetero-PEF system relieved the toxicity and antibacterial property of tetracycline. [ABSTRACT FROM AUTHOR]

The heterogeneous visible-light driven photo-electro-Fenton (H-VL-PEF) system was built to degrade tetracycline using nitrogen/oxygen biomass self-doped porous carbon (NO/PC) cathode catalyst coupling CuFeO 2 /biochar particle catalyst. The NO/PC possessed the H 2 O 2 selectivity of 85.3%, and the gas diffusion electrode with NO/PC as cathode catalyst (NO/PC-GDE) exhibited fine H 2 O 2 electrogeneration performance and stability. The generated electrons on CuFeO 2 /biochar by electrostatic induction and light excitation promoted Fe3+/ Fe2+ and Cu2+/ Cu+ redox cycle, which was beneficial for HO•/O 2 •- formation and tetracycline degradation. The introduction of CuFeO 2 /biochar catalyst and visible light could reduce energy consumption and promote tetracycline mineralization. The CuFeO 2 /biochar loads, initial pH and current density of H-VL-PEF system were optimized. The degradation pathway of tetracycline was speculated based on the intermediates identified by HPLC/MS. Escherichia coli growth inhibition experiments and toxicity prediction analysis demonstrated that the comprehensive toxicity of tetracycline was alleviated due to the catalytic degradation of H-VL-PEF system. [Display omitted] • Heterogeneous visible-light driven photo-electro-Fenton (H-VL-PEF) system was built. • Nitrogen/oxygen biomass self-doped porous carbon (NO/PC) had fine H 2 O 2 selectivity. • Cathode with NO/PC as electrocatalyst had good stability for H 2 O 2 generation. • H-VL-PEF system promoted regeneration of Fe2+ and Cu+ on CuFeO 2 /biochar catalyst. • The toxicity was alleviated after tetracycline was degraded in H-VL-PEF system. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuFeO2/NPC composites were prepared at no nitrogen sources and reductant. • CuFeO2/NPC can effectively activate PDS to degrade nimesulide. • The OH, SO4- and 1O2 were the main reactive species for nimesulide degradation. • Mechanism of PDS activated by CuFeO2/NPC was clarified in detail. • Degradation pathway was proposed combined with HPLC/MS spectra and DFT calculation. The nitrogen self-doped porous carbons (NPCs) were prepared using alfalfa as raw material by pyrolysis method without additional nitrogen sources at various pyrolysis temperatures. The NPC supported CuFeO 2 (CuFeO 2 /NPC) composites with large BET surface area (113.18 - 517.56 m2 g−1) were successfully prepared by hydrothermal method without reductant. The NPC prepared at 600 °C (NPC-600) supported CuFeO 2 (CuFeO 2 /NPC-600) possessed the highest catalytic performance for activating peroxydisulfate (PDS) to degrade nimesulide compared to other CuFeO 2 /NPC composites. The OH, SO 4 - and 1O 2 were the main reactive species for nimesulide degradation. The oxygen-containing functional groups, pyridinic N, graphitic N, and Fe3+/Fe2+ and Cu2+/Cu+ redox cycles were demonstrated to be extremely important in activating PDS to produce reactive species. The degradation pathway of nimesulide was proposed combined with the HPLC/MS spectra and DFT calculation, and the overall toxicity of nimesulide were effectively alleviated in CuFeO 2 /NPC-600+PDS system according to toxicity prediction. [ABSTRACT FROM AUTHOR]