Fine-tuning the interfacial electron-transfer pathway to regulate the d-orbital occupancy of catalytic center atoms remains a challenge in constructing high-performance photocatalysts for N2 fixation. Herein, an Au-induced interfacial electron-transfer reversal strategy is established by constructing a core-shell Au NPs@MoS2 cocatalyst on an aluminum-based porphyrin metal-organic framework, Al-PMOF(Fe). Both experimental and theoretical results confirm that the embedded Au nanoparticles act as interfacial electronic mediators rather than independent active sites, thereby reversing the intrinsic electron-transfer direction between Al-PMOF(Fe) and MoS2 and increasing the electron density of Mo 4d orbitals. This process modulates the Mo 4d orbital occupancy and generates electron-rich Mo sites, thereby enhancing electron injection into the π* antibonding orbitals of adsorbed N2 and promoting N2 activation. Consequently, the optimized catalyst achieves an NH3 production rate of 183.3 μmol gcat.−1 h−1 and an apparent quantum efficiency of 0.38% at 420 nm. This work highlights the significance of manipulating the d-orbital electron occupancy of catalytic center atoms through interfacial electron-transfer reversal for the rational design of efficient photocatalysts for N2 fixation.

Peroxymonosulfate (PMS)-based advanced oxidation represents a promising route for aqueous micropollutant degradation, yet its efficiency hinges on developing robust activation strategies. Herein, we demonstrate that strategic cobalt doping into BaTiO3 lattice creates a highly efficient photocatalyst for PMS activation under simulated solar illumination. XANES and EXAFS analysis demonstrated that Co ions occupy octahedral Ti4+ sites with mixed +2/+3 valence states, forming integrated Co-O-Ti/Ba coordination within the perovskite framework. This atomic-level engineering modulates the electronic structure, extends visible-light absorption, and dramatically enhances charge carrier separation and migration. The optimized 3.5%Co-BTO catalyst exhibits exceptional activity, achieving 95.3% CBZ degradation within 10 min, with a rate constant 9.1 times greater than pristine BTO. Mechanistic investigations reveal that singlet oxygen (1O2) serves as the dominant reactive species, while DFT calculations illustrate that Co doping introduces mid-gap states near the Fermi level, facilitating electron transfer and strengthening PMS adsorption. The established Co2+/Co3+ redox cycle enables sustained PMS activation. Toxicity evaluation confirms effective detoxification of the parent pollutant. This work provides fundamental insights into the rational design of ferroelectric perovskite catalysts for synergistic photocatalysis-PMS processes, advancing the frontier of catalytic water purification technologies.

Fine-tuning the chemical microenvironment of catalytic center atoms to achieve efficient N2 adsorption and activation remains a challenge in the development of high-performance photocatalysts for N2 fixation. Herein, a pathway for fine-tuning the chemical microenvironment of catalytic center atoms to enable efficient N2 adsorption and activation was established by bridging Au nanoclusters (Au NCs) and Zr-O clusters of a Zr-based porphyrin metal-organic framework (PCN-221(Fe)) using p-aminobenzoic acid. Both experimental and theoretical results confirm that this strategy facilitates electron transfer from the 3d orbitals of the Fe atoms to the Au nanoclusters, increasing the unoccupied states in the 3d orbitals and effectively promoting N2 adsorption. In addition, the porphyrin unit with high photosensitivity can generate electrons under light excitation and inject them into the Fe-N-N* sites, thereby promoting N2 activation. Consequently, the optimized catalyst achieved a favorable activity toward NH3 production with a rate of 150.9 mu mol g- 1 h- 1, and an apparent quantum efficiency (AQE) of 0.27% at 520 nm. This work underscores the significance of manipulating the d-orbital electron structure of catalytic center atoms at the molecular level for the rational design of efficient photocatalysts for N2 fixation.

Rational design of interfacial chemical bonds is crucial for reducing charge transfer barriers in heterojunction photocatalytic materials, yet this remains a challenge. Herein, we report a novel CQD/In2S3 heterojunction with interfacial In–O bonds, fabricated via an in-situ reaction between biomass-derived carbon quantum dots (CQDs) and sulfur-vacancy-rich In2S3 nanosheets. Experiments and density functional theory (DFT) calculations confirm the formation of In–O bonds between oxygen atoms on the CQD surface and coordinatively unsaturated indium sites in In2S3, which provide fast channels for interfacial electron transfer. In addition, an ohmic contact is formed between CQDs and In2S3, and the resulting internal electric field drives the transfer of photogenerated electrons toward CQDs. As a result, the optimized catalyst exhibits a prolonged carrier lifetime of 1627.0 ps, as revealed by femtosecond transient absorption (fs-TA) spectroscopy, thereby promoting the efficient generation of superoxide radicals and holes. Consequently, the catalyst achieves a tetracycline (TC) removal efficiency of 81.5% within 60 min, with a kinetic rate constant of 0.107 L mg−1 min−1, outperforming defective In2S3 by a factor of 2.1. Based on theoretical and experimental findings, three possible TC removal pathways are proposed. This work provides an effective interface engineering strategy for the design of metal sulfide-based heterojunctions and enables the high-value utilization of waste biomass in photocatalytic materials.

Solar-driven interfacial evaporation technology for saline water desalination, with advantages such as environmental friendliness and low cost, is of great significance for alleviating global water scarcity. However, salt scaling on the evaporator surface can reduce the evaporation rate and seriously threaten the system stability. Here, a sustainable inverted cone-shaped solar evaporator was fabricated using Ulva prolifera and sodium alginate as raw materials, achieving the synergy of efficient freshwater production and salt recovery. Under 1 sun irradiation, the fully marine biomass-based evaporator exhibited evaporation rates of 3.37 kg center dot m- 2 center dot h- 1 and 3.02 kg center dot m- 2 center dot h- 1 for 3.5 wt% and 10 wt% NaCl solutions, respectively, with no significant decay after 5 cycles. The unique 3D inverted-cone structure combined with the concentration gradient-induced Marangoni convection (verified by COMSOL simulation) promoted the saline radial transport and directional crystallization, enabling a salt collection rate of 3.13 kg center dot m- 2 center dot day- 1 in 10 wt% NaCl. Furthermore, laboratory and outdoor performance tests using simulated seawater and real seawater demonstrated its application potential. This study provides a novel strategy for efficient seawater desalination and resource utilization.

Titania mesocrystals of rod-like shape (TR), assembled from crystallographically-oriented nanocrystals, have attracted particular attention in the field of photocatalysis, but their preparation is highly dependent on used surfactants and/or templates. In this study, a new method of titania mesocrystals' synthesis has been proposed by solvothermal reaction, without participation of any morphology-control agents. A mechanism of their formation, involving crystal nucleation, growth, and oriented arrangement (along the (101) direction) has been established. It has been found that an increase in reaction temperature accelerates growth and nucleation of grains, whereas prolonged reaction promotes their elongation. This specific morphology results in high photocatalytic activity under UV irradiation towards both oxidation and reduction reactions, including oxidative decomposition of antibiotics, hydrogen evolution and carbon dioxide reduction. Additionally, surface modification of titania mesocrystals with only 2 wt% of noble metal (NM: palladium, platinum, gold, silver and copper) causes a significant increase in photocatalytic performance under UV/vis, depending mostly on the formed Schottky barrier high (SBH), and thus the activity increases in the following order: Ag/TR < Au/TR < Pd/TR < Pt/TR. However, in the case of oxidative degradation of tetracycline under vis and carbon monoxide formation under UV, Ag/TR and Cu/TR exhibit the best performance, which could be caused by their mixed-oxidation state, and thus the complex mechanism of their action. Interestingly, the selectivity of CO2 reduction depends on the kind of NM, and thus CO is mainly formed on Ag/TR sample, whereas CH4 on Pd/TR. Moreover, finite-difference time-domain (FDTD) simulations reveal that NM nanoparticles (NPs) induce strong localized electromagnetic (light) field enhancement at the NM-titania interface, with E-field intensities reaching up to 500 x at plasmonic hotspots. While the global scattering cross-section of the titania micro-tubular structure dominates over absorption, the simulations demonstrate that small NPs (20 nm) efficiently convert this scattered light into localized absorption, creating intense near-field enhancement. This plasmonic focusing effect could explain the observed photocatalytic activity enhancement, as the concentrated light fields promote an efficient generation of charge carriers and interfacial electron transfer.

The dynamic regulation of electronic structures of catalysts at interfaces is essential for enhancing solid-liquid heterogeneous catalytic reactions. Here, we report a plasmon-mediated continuous electron transfer strategy to trigger in situ surface reconstruction of Ni1-x Cu x layered double hydroxide (Ni1-x Cu x LDH) for efficient ammonia oxidation reaction (AOR). By electrostatically assembling Au nanoparticles (Au NPs) onto Ni1-x Cu x LDH nanosheets, we establish a heterointerface that enables spontaneous electron transfer from LDH to Au NPs. Under 540 nm light irradiation, localized surface plasmon resonance excitation of Au NPs generates hot holes that act as dynamic electron acceptors, continuously extracting electrons from the LDH support. This process lowers the potential required for surface reconstruction into the active gamma-Ni1-x Cu x OOH species. As a result, the Au-Ni1-x Cu x LDH catalyst achieves an onset potential of only 1.38 V at 5 mA cm-2 and a Tafel slope of 45.27 mV dec-1 under illumination, significantly outperforming pristine LDH and dark conditions. The photoelectrochemical analyses further confirm that LSPR-induced hot holes promote the formation of high-valence Ni species, enhancing AOR kinetics and N2 selectivity. This work establishes plasmon-mediated surface reconstruction as a viable route for designing adaptive, energy-efficient electrocatalysts for ammonia oxidation and beyond.

The persistent presence of tetracycline (TC) in aquatic environments demands advanced oxidation processes capable of efficiently degrading this micropollutant. Although peroxymonosulfate (PMS)-based catalysis shows promise in this regard, its practical efficiency is limited by sluggish activation kinetics and rapid charge recombination, necessitating the development of high-performance catalysts. Herein, we present a strategically engineered cobalt-doped tubular carbon nitride (Co-TCN) that integrates morphological control with atomic-level doping to achieve enhanced photocatalytic PMS activation. The unique tubular architecture of TCN improves light harvesting and facilitates mass transfer, while atomically dispersed cobalt species, confirmed by XAS and XPS, act as efficient electron traps and active sites for PMS activation. This synergistic design yields a catalyst with an increased specific surface area, significantly suppressed charge recombination, and accelerated electron transfer. Under visible light, the optimized 1.1%Co-TCN/PMS system achieved a TC degradation rate constant of 15.87 x 10-2 (mg L-1)-1min-1, which was 15.6-fold higher than that of PMS alone and demonstrates remarkable performance across various antibiotics. Mechanistic investigations reveal a catalytic cycle involving Co2+/Co3+ redox pairs, generating both radical species (SO4(center dot)-, (OH)-O-center dot, (center dot)O2-) and non-radical species (1O2). Furthermore, toxicity assessment confirmed the effective detoxification of TC during the degradation process. This work establishes a novel strategy for designing cost-effective, non-precious-metal-based photocatalysts through concurrent structural and electronic modulation, offering a promising approach for sustainable water treatment.

The climate crisis and global pollution urgently require cheap and sustainable methods to produce materials and clean ecosystems, such as photocatalysis that uses solar energy. Nonetheless, actual photocatalysts are limited by poor light absorption, low redox ability, high cost, and low efficiency. Here, we review the photocatalysis using carbon quantum dot (CQDs)-based nanomaterials, focusing on their synthesis, co-catalysts, single photocatalysts, and heterostructures through coordination of inorganic and organic semiconductors. They have low preparation cost, ultra-low ecological toxicity, favorable dispersibility, unique optical properties, and photoinduced charge transfer properties. Discovered in 2004, they have been applied in photocatalytic degradation of various organic pollutants, carbon dioxide reduction, hydrogen evolution, photocatalytic sterilization, organic synthesis, and hydrogen peroxide production. We compare the top-down and bottom-up preparation strategies for CQDs, presenting their recent applications in wastewater treatment, sterilization, degradation of gaseous pollutants, and the production of valuable chemicals. Lastly, with the emergence of defective CQDs, these materials appear promising for photocatalytic remediation technologies and the production of useful chemicals.

A Ni/N–C catalyst coupled with a water-electrode DBD plasma reactor enables efficient CH 4 –CO 2 reforming, promoting selective CO and H 2 production through plasma–catalyst synergy.

The liquid-phase approach is the primary route for producing carbon quantum dots (CQDs), but its complicated purification process and low product yield restrict the large-scale production and application of CQDs. In this work, CQD powder was generated via a facile one-step pyrolysis reaction using glucose and boric acid as precursors without the need for solvents. Notably, the product yield of the CQD powder reaches 76.0 %, exceeding that of most previously reported results. This approach is green and efficient, as it eliminates the need for sophisticated instrumentation, hazardous chemicals, and tedious purification procedures. X-ray photoelectron spectroscopy (XPS) reveals that the surface of the CQDs contains abundant B, O, and other functional groups, which improve their dispersion stability while suppressing the fluorescence quenching induced by particle aggregation. The CQDs show green fluorescence in solid powder and blue-green fluorescence in solution (quantum yield = 15.9 %), both of which exhibit excitation-dependent emission behavior. The synthesized CQD powder exhibits favorable compatibility with polyvinyl alcohol (PVA)-based hydrogels, allowing for the formulation of a stable CQD/PVA fluorescent ink. This hydrogel-based ink possesses favorable rheological properties, allowing precise patterning on polyethylene terephthalate (PET) substrates via 3D printing technology. This capability highlights its promising potential for direct ink writing and anti-counterfeiting applications. This work offers a sustainable and effective approach for the large-scale preparation of CQDs, highlighting the high-value utilization of CQDs in creating fluorescent anticounterfeiting inks.

Hydrogel-based solar interfacial evaporation for seawater desalination is limited by inadequate evaporation rates and inefficient light harvesting, particularly under non-perpendicular illumination. Herein, This study introduces a peony-like single-layer graphene oxide (SLGO)/polyvinyl alcohol (PVA) 3D hydrogel evaporator (GPH) featuring a geometric light-trapping architecture. By exploiting synergistic edge curvature gradients and surface aperiodic wrinkles, the GPH induces multiple internal reflections to effectively manipulate the optical path, thereby overcoming the light absorption limitations of conventional evaporators under oblique incidence. Beyond optical management, precisely tuning the SLGO/PVA ratio optimizes the polymer network's hydrogen bonding, which elevates the intermediate/free water ratio to 0.78 and drastically reduces the water evaporation enthalpy to 1248 J g-1 (cf. 2450 J g-1 for bulk water). Consequently, an exceptional evaporation rate of 2.761 kg m-2 h-1 (20% enhancement over conventional homogeneous hydrogels) and energy efficiency of 91.61% are achieved under 1-sun intensity. Crucially, the hierarchical 3D porous architecture facilitates rapid water replenishment and efficient ion diffusion, endowing the evaporator with robust salt-rejection capabilities. Moreover, the GPH demonstrates outstanding mechanical robustness, with a high fracture strain of 800% in uniaxial tensile tests, indicating its resilience and potential for practical application. This work presents a promising pathway for efficient, reliable seawater desalination and offers a novel perspective for next-generation interfacial solar evaporation technologies.

Hydrogen production via photocatalytic water splitting offers a sustainable pathway to address global energy and environmental challenges. Among various photocatalysts, metal–organic frameworks (MOFs) have emerged as highly promising platforms owing to their structural tunability, well-defined porosity, and modular integration of light-harvesting and catalytic functionalities. However, precise identification of active sites at the atomic level and a clear understanding of structure–performance relationships remain significant challenges. This review critically examines recent advances in MOF-based systems, with a focus on elucidating structure–performance correlations and strategies to overcome thermodynamic and kinetic limitations. Key approaches, including linker engineering, node modulation, heterostructure construction and the development of conductive MOF derivatives are discussed. Furthermore, advanced characterization techniques are presented to elucidate charge carrier dynamics and underlying reaction pathways. Finally, remaining challenges related to overall water splitting, long-term stability, scalability, and standardized evaluation protocols are outlined, along with future research directions.

Precisely modulating the synergistic effect of N-2 reduction and H2O oxidation reactions at the molecular level for photocatalytic N-2 fixation remains a challenge. Herein, MnOx and Pt nanoparticles (NPs) were decorated onto amine-functionalized metal organic framework NM-Fe {NH2-MIL-101(Fe)}, attempting to promote photoredox reactions simultaneously. Benefiting from the synergy of redox reactions, the optimized Pt@NM-Fe/MnOx exhibits an NH3 production rate of ca. 340 mu mol g(-1) h(-1), which is 4.5 times that of NM-Fe, along with an apparent quantum efficiency (AQE) of 0.33% at 420 nm. N-15 isotope labeling experiments demonstrates that the N in the nitrogen reduction reaction (NRR) originated exclusively from N-2. The performance improvement can be attributed to the spatial synergy of N-2 reduction and H2O oxidation reactions on the Pt@NM-Fe/MnOx composite photocatalyst. More specifically, MnOx acts as the H2O oxidation site by capturing holes to generate H+, while NM-Fe serves as the N-2 reduction center by accepting electrons. MnOx captures holes to oxidize H2O into H+, while Pt NPs activate the generated H+ into *H for photocatalytic N-2 fixation. Density functional theory calculations indicate that the breakage of the O-H bond in the H2O oxidation process is synchronized with the formation of *NNH in N-2 reduction, lowering the energy barrier. The present work demonstrates a synergistic integration strategy that overcomes the kinetic mismatch between the two half-reactions through precise spatial modulation of functional sites.

Lead (Pb), a highly toxic heavy metal, readily migrates and accumulates in water and soil, posing severe threats to the ecological environment and human health. Efficient removal of Pb(II) ions is thus critical for environmental pollution control. Herein, a novel ternary biomimetic composite sponge (MoS2-PVA-SA, MPS) with an interpenetrating porous network structure was innovatively fabricated by integrating molybdenum disulfide (MoS2) nanosheets into an organic polymer matrix via freeze-drying combined with chemical crosslinking. The MPS sponge exhibits ultrafast Pb(II) adsorption following pseudo-second-order kinetics, with a remarkable maximum adsorption capacity of 1586.03 mg & sdot;g-1, significantly outperforming most reported MoS2-based adsorbents. Mechanistic studies reveal that the strong chemical affinity between soft-base sulfur atoms on MoS2 surfaces and soft-acid Pb(II) cations, together with synergistic interactions from active groups in sodium alginate (SA), jointly contribute to the superior Pb(II) removal efficiency. Meanwhile, the flexible polyvinyl alcohol (PVA) crosslinking network endows the composite sponge with excellent mechanical strength and durability, maintaining structural integrity and adsorption performance during repeated use. Featuring facile synthesis, exceptional adsorption capacity, and good reusability, the MPS composite sponge demonstrates great promise as a high-efficiency adsorbent for practical remediation of lead-contaminated water.

Simultaneous arsenic (As3+/5+) and mercury (Hg2+) removal in complex mining environments is challenging due to wide pH and temperature fluctuations and the presence of abundant coexisting ions. In this work, a structurally robust FeC-NF@CeO2 adsorbent was developed through Fe3+ incorporation and the loading of CeO2 nano-active particles, enabling efficient As3+/5+/ Hg2+ co-removal. The developed FeC-NF@CeO2 exhibited enhanced structural integrity, stable CeO2 anchoring, and favorable interfacial affinity, leading to preferential adsorption of As3+/5+and Hg2+ toward multiple toxic heavy metals. The maximum adsorption capacities for As3+/5+ and Hg2+ reached 49.02 and 167.95 mg/g, respectively. The adsorbent maintained excellent removal performance at an initial As3+/5+ and Hg2+ concentration of 2 mg/L, achieving minimum residual concentrations of 0.3 and 0.7 μg/L, respectively, with negligible interference from common coexisting anions and cations. Furthermore, FeC-NF@CeO2 maintained stable arsenic and mercury removal efficiencies over repeated adsorption-desorption cycles. Mechanistic investigations revealed that adsorption was primarily occurred through ligand exchange between surface hydroxyl groups and metal ions, while density functional theory (DFT) calculations demonstrated stronger charge transfer interactions for arsenic species with adsorption energy 2.5 times higher than that of mercury species on the FeC-NF@CeO2 surface. Overall, FeC-NF@CeO2 represents a promising adsorbent for the efficient remediation of arsenic- and mercury-contaminated groundwater under chemically complex environment conditions.

Sluggish kinetics of overall water splitting and high costs of sacrificial agent-dependent H2 evolution have severely restricted the scale application of light-driven hydrogen production technology. The value-added oxidation of benzyl alcohol (BA) has emerged as an ideal candidate to circumvent the aforementioned obstacles. However, developing highly active photocatalysts is pivotal for efficient catalytic photo-redox. Herein, carbon (C)-heteroatoms were doped into the CdS lattice, and Au-cocatalyst was subsequently decorated to prepare the Au-decorated, C-doped CdS for achieving exceptional co-production of benzaldehyde (31.29 mmol·g-1·h-1) and H2 (24.37 mmol·g-1·h-1), delivering an apparent quantum efficiency of 5.08% under 420 nm-photoirradiation. Density functional theory calculations revealed that the C-heteroatoms, leveraging their intrinsic electron-trapping effect, could rapidly accumulate photoexcited electrons from CdS, thereby acting as active sites for H2 evolution. In contrast, the Au nanococatalyst, benefiting from its strong surface plasmon resonance effect, injected resonant electrons into CdS and served as the active center for BA oxidation. Experimental results provided direct evidences to validate the theoretical conclusions, while H isotope tracing further verified the synergy of the collaborative reaction process. This study proposes a dual-mechanism strategy for improving the redox photoactivity of CdS photocatalysts by integrating heteroatom-doping and surface metal cocatalysis.

Discovered in 1939, the traditional anthraquinone method has been utilized to manufacture over 95% of the valuable chemical hydrogen peroxide (H2O2) industrially, resulting in high energy consumption and the generation of hazardous secondary by-products. Calling for the photocatalysis processes, it has been demonstrated that the sluggish kinetics of the oxygen reduction reaction (ORR), water oxidation reaction (WOR), and severe electron-hole pairs recombination make the non-sacrificial H2O2 photoproduction challenging. To overcome these challenges, covalent organic frameworks (COFs), a well-known carbon-based material, have been considered one of the most powerful photocatalytic feedstocks for non-sacrificial H2O2 photosynthesis, especially in natural seawater. Herein, we summarize the recent advances made in COF catalysts, preparation strategies, and their application for H2O2 photosynthesis in pure water and natural seawater. The relevant content of theoretical simulations, structural characterizations, future prospects, and limitations is also discussed elaborately and critically. We anticipate that this review will furnish insight into current progress and inspire the progress of next-generation photocatalytic materials for sustainable and non-sacrificial H2O2 photoproduction, especially in seawater as a natural source.