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• A novel electrified membrane was fabricated to remove and degrade organic pollutants. • Sequential anodic oxidation and cathodic electro-Fenton was created in a Janus membrane. • Organic pollutants were first directly oxidized on the Ti 4 O 7 anode. • The cathodic ·OH further enhanced the mineralization of organic pollutants. • The reagent-free electrified membrane is competitive and universal in pollutant removal. Electrified membrane technologies have recently demonstrated high potential in tackling water pollution, yet their practical applications are challenged by relying on large precursor doses. Here, we developed a Janus porous membrane (JPEM) with synergic direct oxidation by Magnéli phase Ti 4 O 7 anode and electro-Fenton reactions by CuFe 2 O 4 cathode. Organic pollutants were first directly oxidized on the Ti 4 O 7 anode, where the extracted electrons from pollutants were transported to the cathode for electro-Fenton production of hydroxyl radical (·OH). The cathodic ·OH further enhanced the mineralization of organic pollutant degradation intermediates. With the sequential anodic and cathodic oxidation processes, the reagent-free JPEM showed competitive performance in rapid degradation (removal rate of 0.417 mg L−1 s−1) and mineralization (68.7 % decrease in TOC) of sulfamethoxazole. The JPEM system displayed general performance to remove phenol, carbamazepine, and perfluorooctanoic acid. The JPEM runs solely on electricity and oxygen that is comparable to that of PEM relies on large precursor doses and, therefore, operation friendly and environmental sustainability. The high pollutant removal and mineralization achieved by rational design of the reaction processes sheds light on a new approach for constructing an efficient electrified membrane. [Display omitted] [ABSTRACT FROM AUTHOR]

Activating metal ion‐doped oxides as visible‐light‐responsive photocatalysts requires intricate structural and electronic engineering, a task with inherent challenges. In this study, we employed a solid (template)‐molten (dopants) reaction to synthesize Bi‐ and Rh‐codoped SrTiO3 (SrTiO3 : Bi,Rh) particles. Our investigation reveals that SrTiO3 : Bi,Rh manifests as single‐crystalline particles in a core (undoped)/shell (doped) structure. Furthermore, it exhibits a well‐stabilized Rh3+ energy state for visible‐light response without introducing undesirable trapping states. This precisely engineered structure and electronic configuration promoted the generation of high‐concentration and long‐lived free electrons, as well as facilitated their transfer to cocatalysts for H2 evolution. Impressively, SrTiO3 : Bi,Rh achieved an exceptional apparent quantum yield (AQY) of 18.9 % at 420 nm, setting a new benchmark among Rh‐doped‐based SrTiO3 materials. Furthermore, when integrated into an all‐solid‐state Z‐Scheme system with Mo‐doped BiVO4 and reduced graphene oxide, SrTiO3 : Bi,Rh enabled water splitting with an AQY of 7.1 % at 420 nm. This work underscores the significance of simultaneous structural and electronic engineering and introduces the solid‐molten reaction as a viable approach for this purpose. [ABSTRACT FROM AUTHOR]

Nanomaterial hydrophobicity plays a critical role in interfacial phenomena ranging from biological toxicity to chemical reactions. However, it is difficult to figure out the high‐resolution surface hydrophobicity at the nanoscale. Herein, a chemical force microscopy is demonstrated to profile in situ hydrophobicity images with the nanoscale resolution, exhibiting order‐of‐magnitude gain than the traditional methods. This method is utilized to rapidly recognize the spatial fine structure hydrophobicity on Au, graphite, mica, and graphene oxides (GO), enabling the recognition of complicated substances and structures. It is found that the hydrophobicity of GO is opaque and is independent of stacking thickness, which is entirely different from the original graphene. Especially, the regions of wrinkles/edges are first proved to be generally less attractive to the hydrophobic probe than flat areas. This method is used to observe the dynamic evolution of GO hydrophobicity in different aqueous conditions, and is capable of detecting local oxidation variation during interfacial reactions. [ABSTRACT FROM AUTHOR]

The demands for green production of hydrogen peroxide have triggered extensive studies in the photocatalytic synthesis, but most photocatalysts suffer from rapid charge recombination and poor 2e− oxygen reduction reaction (ORR) selectivity. Here, a novel composite photocatalyst of cyano‐rich graphitic carbon nitride g‐C3N4 is fabricated in a facile manner by sodium chloride‐assisted calcination on dicyandiamide. The obtained photocatalysts exhibit superior activity (7.01 mm h−1 under λ ≥ 420 nm, 16.05 mm h−1 under simulated sun conditions) for H2O2 production and 93% selectivity for 2e− ORR, much higher than that of the state‐of‐the‐art photocatalyst. The porous g‐C3N4 with Na dopants and cyano groups simultaneously optimize two limiting steps of the photocatalytic 2e− ORR: photoactivity, and selectivity. The cyano groups can adjust the band structure of g‐C3N4 to achieve high activity. They also serve as oxygen adsorption sites, in which local charge polarization facilitates O2 adsorption and protonation. With the aid of Na+, the O2 is reduced to produce more superoxide radicals as the intermediate products for H2O2 synthesis. This work provides a facile approach to simultaneously tune photocatalytic activity and 2e− ORR selectivity for boosting H2O2 production, and then paves the way for the practical application of g‐C3N4 in environmental remediation and energy supply. [ABSTRACT FROM AUTHOR]

The demands for efficient and robust heterogeneous hydrogenation catalysts have triggered extensive research to optimize the structures of metal catalytic centers, but the potential of support construction for enhanced hydrogenation performance has been overlooked. This study introduces a hierarchically ordered porous poly(2,6‐diaminopyridine) (PDAP) as a Pd nanoparticle support for hydrogenation removal of recalcitrant pollutants in water purification. The PDAP support acts as a sorbent and microreactor to enhance the proximity of targeted water pollutants and reactive hydrogen atom species, achieving unprecedently high water purification efficiency. The PDAP support also acts as a catalyst in mediating peroxide‐activation for oxidative destruction of Pd poisons (e.g., reduced sulfur), achieving in situ regeneration of poisoned Pd catalysis centers. The high activity and in situ regenerativity achieved by rational construction of the support structure sheds light on a new approach for designing efficient and robust heterogeneous hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

• We report the quantum yield (QY) spectrum of PPRIs from black carbon (BC). • PPRIs QYs from BC are highly dependent on pyrolysis temperature and size. • BC from different biomasses display unexpected small variation in PPRIs QYs. • Optical and surface redox characteristics of BC determines PPRIs QYs. Black carbon (BC) is ubiquitous in sunlit waters and atomosphere. Recent studies revealed that under sunlight irradiation BC is photoactive on producing photochemically produced reactive intermediates (PPRIs), a group of key species in accelerating earth's surface biogeochemical processes and pollutant dynamics. Nevertheless, reported PPRIs productions from BC exhibit large inconsistency and the intrinsic capacities of BC in producing PPRIs remain poorly characterized. This work provided a wavelength-dependent quantum yields (QYs) assessment of four environmentally-relevant PPRIs (excited triplet state BC (3BC*), singlet oxygen (1O 2), hydrogen peroxide (H 2 O 2), and hydroxyl radical (·OH)) from various BC. The QYs of all investigated PPRIs exhibit high dependence on incident light wavelength. For instance, the QYs of 1O 2 dramatically decreased from 4.4% to 0.4% with light wavelength increasing from 375 to 490 nm and decreased to 0 above 490 nm. Suprisingly, PPRIs QYs only varied by 2.0–2.5-fold among BC prepared from different biomasses (i.e., pine needle, shell, straw, and wood), while the pyrolysis temperature and size of BC demonstrate higher impacts on the PPRIs QYs by up to 30.3- and 7.1-fold variations, respectively. Analyses on the physicochemical properties of BC demonstrate that QYs of 3BC* and 1O 2 were linked to the optical properties of BC, while the QYs of H 2 O 2 and ·OH were determined by multiple factors including the surface redox characteristics. Further, PPRIs productions from BC follow similar paths and efficiencies compared to those from natural organic matter. The revealed QYs of BC-derived PPRIs establish a key basis for evaluating PPRIs-mediated element cycles and pollutant transformation in natural waters, which are becoming increasingly important in the context of higher BC input from more frequent wildfires and artificial sources. [Display omitted] [ABSTRACT FROM AUTHOR]

• Soil-water interface (SWI) was an unrecognized hotspot for PPRI photoproduction. • Photochemical •OH production at SWI was enhanced by one order of magnitude. • Nationwide surveys demonstrated SWI as ubiquitous PPRI hotspot in wetlands. • Elevated SWI PPRI production accelerated nutrient and pollutant transformation. Photochemically produced reactive intermediates (PPRIs) formed by sunlight-irradiation of natural photosensitizers play critical roles in accelerating biogeochemical cycles on earth surface. Existing PPRI studies mostly focus on bulk phase reactions (e.g., bulk water), with PPRI processes at the environmental interfaces largely unexplored. Here, we report the wetland soil-water interface (SWI) as a widespread but previously unappreciated hotspot for PPRI productions. Massive productions of four important PPRI species (i.e., triplet-state excited organic matter (3OM*), singlet oxygen (1O 2), hydrogen peroxide (H 2 O 2), and hydroxyl radical (•OH)) were observed at the SWI. All four PPRI species exhibited higher productions at the SWI than those in bulk water, where •OH production was largely elevated by up to one order of magnitude. The enhanced PPRI productions at the SWI were caused by intensified photon absorption and vibrant Fe-mediated redox processes, where the light absorption by less- or non-photoactive soil substances partially offset the enhancement on PPRI productions. Nationwide wetland investigations demonstrate that the SWI was a ubiquitous hotspot for PPRI productions. Simulations on PPRIs-mediated reactions suggest that the enhanced PPRI productions could greatly affect the kinetics and transformation pathways of nutrients and pollutants. Given that the SWI also acts a hotspot for nutrient and pollutant accumulation, incorporating the SWI enhanced PPRI productions into biogeochemical process assessments is pivotal for advancing our understandings on the element cycles and pollutant dynamics in wetlands. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalytic oxygen reduction is a promising strategy to generate H 2 O 2 in a low-energy input and more sustainable way. Despite great progress have made in photocatalyst design, the rate-limiting step that poor accessibility of the O 2 to photocatalysts in water remains unexplored. Here, we design a solid-liquid-air triphasic interface over a melamine foam to boost the interfacial O 2 transportation. A Wenzel-Cassie state coexists in a hydrophobic interface and form a tubular confined space with a thickness of 100 µm, which allows the O 2 directly transferred to the photocatalyst from the air, greatly boost the formation of H 2 O 2. In addition, a tubular confined microenvironment formed on the surface greatly enhances oxygen diffusion, and suppressed the unwanted decomposition of H 2 O 2. This surface microenvironment engineering resulted in a 10-fold enhancement in the photosynthesis H 2 O 2 compared to the traditional solid-liquid diphase system, pinpointing the necessary O 2 mass diffusion for photocatalytic H 2 O 2 generation. [Display omitted] • A solid-liquid-air triphasic interface with tubular confined structure is fabricated. • The Wenzel-Cassie state coexists in a hydrophobic interface as a tubular confined space. • A gas diffusion layer is consisted of a loose skeleton and interconnected network. • Triphasic interface enhances O 2 diffusion, and suppressed the decomposition of H 2 O 2. • Photocatalytic H 2 O 2 at a triphasic interface is 10-fold enhanced over at diphase system. [ABSTRACT FROM AUTHOR]

The PDAP support also acts as a catalyst in mediating peroxide-activation for oxidative destruction of Pd poisons. Keywords: hydrogenation; in situ regeneration; microreactors; support construction EN hydrogenation in situ regeneration microreactors support construction 1 1 1 05/28/21 20210526 NES 210526 In article number 2100971, Chiheng Chu and co-workers introduce hierarchically ordered porous poly(2,6-diaminopyridine) (PDAP) as a Pd nanoparticle support for hydrogenation removal of recalcitrant pollutants in water purification. Heterogeneous Hydrogenation Catalysts: Constructing the Support as a Microreactor and Regenerator for Highly Active and In Situ Regenerative Hydrogenation Catalyst (Adv. Funct. [Extracted from the article]