Electrode materials are pivotal to advancing the deployment of photoelectrochemical (PEC) seawater splitting. Carbon materials hold great potential for modifying semiconductors to fabricate high-performance photocathodes, but are limited in seawater by the Ca2+ and Mg2+. Herein, a microwave-synthesized carbon dots (m-CDs) were demonstrated as electron donors in composite photocathode materials to enhance their performance for seawater splitting. The as-prepared m-CDs/CuBi2O4 photocathode exhibited a photocurrent density of 0.183 mA cm- 2 at 0.4 V vs. RHE in simulated seawater, which was outperforming the pristine CuBi2O4 (0.102 mA cm- 2) and hydrothermal-synthesized carbon dots (h-CDs) modified CuBi2O4 (0.106 mA cm- 2) samples. The structural characterization results show that the surface of m-CDs is rich in acidic groups. These functional groups will significantly increase the H+ concentration on the catalyst surface during the HER process, inhibit the rise of surface pH, thereby preventing Ca2+/Mg2+ from forming hydroxides and reducing the catalytic performance. This study not only presents a metal-free carbon material to enhance the photocathode performance for seawater splitting, but also offers a theoretical foundation for the rational design of carbon materials in this field.

Electrocatalytic seawater splitting is a promising technology for sustainable hydrogen production, but its practical application is hindered by the sluggish oxygen evolution reaction (OER) kinetics and corrosion from the chloride ions (Cl ). Here, a strategy of pre-modifying the anode with carbon dots (CDs) before growing nickel-iron layered double hydroxide (NiFe LDH) is reported to improve its activity and stability in seawater (B-CDs/ NiFe LDH). The introduced CDs can efficiently activate high-valent Fe sites and electrostatically repel Cl to protect the nickel foam substrate. Compared to post-modification of CDs, this strategy reduces CDs dosage by 80 %, while achieving comparable OER performance. The synthesized B-CDs/NiFe LDH exhibits an overpotential of 349 mV at 100 mA cm 2 under alkaline seawater conditions, with electrocatalytic stability over 150 h. This work not only presents a viable approach to the fabrication of noble metal-free anodes for stable seawater electrolysis, but also provides theoretical guidance for the subsequent design of such electrode materials.

Herein, we report a separation-free perylene diimide-based supramolecular photocatalyst, enabling the self-stratified co-production of hydrogen peroxide and benzaldehyde. Density functional theory (DFT) calculations confirm that the ATC-PDI exhibits a significantly enhanced molecular dipole moment and reduced exciton binding energy compared to pristine PTCDA. This structural modification not only induces asymmetric charge distribution within the it-conjugated framework but also creates localized oxygen adsorption sites, facilitating efficient separation and directional migration of photogenerated carriers to active sites. Consequently, charge recombination is drastically suppressed, and photocatalytic activity is substantially improved. Notably, the photocatalytic H2O2 production process is coupled with the selective oxidation of benzyl alcohol to benzaldehyde, thereby maximizing the atom economy and catalytic efficiency of the system. Under neutral conditions and simulated solar irradiation (180 W xenon lamp, AM 1.5G), the ATC-PDI catalyst achieves a remarkable H2O2 generation rate of 44.54 mmol center dot g-1 center dot h-1, accompanied by a benzaldehyde production rate of 42.14 mmol center dot g-1 center dot h-1. Mechanism investigations reveal that the dual-functional photocatalysis proceeds via concurrent radical and non-radical pathways, highlighting the versatility of the ATC-PDI system. This work presents an innovative molecular design paradigm for developing highly efficient separation-free photocatalysts for simultaneous H2O2 synthesis and selective organic transformations, opening new avenues for self-stratified chemical production.

Flexible Zn-air batteries (ZABs) are attractive for wearable electronics and low-altitude aerial platforms due to their high theoretical energy density, intrinsic safety, low cost and environmental friendliness. However, their practical application is still limited by the insufficient mechanical stability of gel electrolytes, limited transport behavior and inadequate temperature adaptability. In order to address these problems, a composite hydrogel electrolyte based on acrylamide (AM), polyacrylic acid (PAA) and carbon nanotubes (CNTs) was developed. In this system, AM forms a three-dimensional crosslinked network through polymerization by UV. PAA further enhances the network stability through chain entanglement and hydrogen bonding interactions. Besides, the CNTs mainly function as reinforcing diffusion behavior and help to stabilize the composite network and improve bulk-related transport and diffusion behavior of the hydrogel. The obtained hydrogel exhibits enhanced mechanical stretchability, with an elongation at break of 506

To overcome the limitations of traditional ORR electrocatalyst development, which relies heavily on empirical strategies and single-parameter regulation, an integrated framework combining AI, experimental validation, and theoretical analysis is established. A high-accuracy ridge regression model is developed based on 3375 data points collected from 135 publications, encompassing 4 categories and 24 features. The model enables reliable prediction of the ORR half-wave potential, achieving a test set R2 of 0.90 and an MSE of 0.002. Model analysis together with SHAP interpretation identifies total N content as the dominant descriptor governing ORR activity, while pyrolysis temperature is determined to be the key parameter controlling total N content. On this basis, a regulatory pathway is proposed: modulation of pyrolysis temperature -> variation in total N content -> regulating of half-wave potential. Experimental results demonstrate that every 100 degrees C increases in pyrolysis temperature decreases total N content by 1.7-2.0 at.% and reduces the half-wave potential by 90-130 mV. This regulatory influence is substantially stronger than that induced by adjusting the non-metallic precursor ratio or heating rate. Structural and morphological characterization confirms the successful synthesis of N-doped carbon nanotubes (CN-900). Density functional theory (DFT) calculations further reveal that N doping in CN-900 leads to an optimal reduction in the ORR reaction energy barrier of 0.30 eV. Zinc-air batteries employing CN-900 as the cathode deliver superior electrochemical performance, including an open-circuit voltage of 1.42 V and stable operation over 1200 cycles without noticeable degradation. The assembled battery stack successfully powers a small unmanned aerial vehicle (UAV), demonstrating a viable alternative to lithium-ion batteries for UAV applications. This study establishes an AI-guided paradigm for ORR electrocatalyst development, thereby promoting AI-driven materials design and facilitating the application of zinc-air batteries in the low-altitude economy.

Photocatalytic production of hydrogen peroxide (H2O2) for ballast water sterilization represents an emerging and environmentally benign approach to combat invasive aquatic species. Here, a novel antimony (Sb) and potassium (K) co-doped g-C3N4 (denoted as Cyano-Sb-Trz) was synthesized via a tandem hydrothermal-calcination strategy combined with a one-step molten salt method. Spatially separated redox active sites were constructed through metal doping and the introduction of cyano groups, which enhance the molecular dipole moment and suppress charge carrier recombination. Simultaneously, H2O2 and benzaldehyde (BAD) are produced via both radical pathway and non-radical pathway certified by density functional theory (DFT) calculations and free radical trapping experiments. Under AM 1.5 G irradiation, Cyano-Sb-Trz demonstrates high production rates of 50.1 mmol center dot g- 1 center dot h- 1 for H2O2 and 47.8 mmol center dot g- 1 center dot h- 1 for BAD. Furthermore, Cyano-Sb-Trz generated a cumulative H2O2 concentration of 52.4 mmol center dot L- 1 over 17 h, far beyond the minimum concentration threshold (29.4 mmol center dot L- 1) for practical water treatment applications. This work provides a new conceptual framework for the photocatalytic generation of H2O2.

In studies of the two-electron oxygen reduction reaction (2e- ORR) in seawater, phosphorus-doped carbon-based catalysts are considered highly promising materials. Unlike most catalysts, these materials exhibit enhanced 2eORR performance in chlorine-containing electrolytes. However, because phosphorus adopts diverse doping configurations in carbon materials (e.g., P-C, P-C=O, P-O), the mechanisms by which these configurations interact with Cl- and influence catalyst selectivity and activity remain unclear, hindering further improvements in performance. In this work, phosphorus-doped porous carbon (with P-O as the dominant structure) was synthesized by a liquid-phase method combined with one-step annealing, achieving a hydrogen peroxide (H2O2) production rate of 1.749 mol/g/h and a Faradaic efficiency of 93.77 % in 0.5 M NaCl solution. By integrating structural characterization, performance testing, Pearson Equation and theoretical calculations, this study clarifies the synergistic effect of P-O bond configuration, defect density, and specific surface area on H2O2 selectivity in a NaCl solution. This research provides theoretical support for the design of non-metallic catalysts resistant to Cl-poisoning and promotes the application of H2O2 production technology via seawater electrolysis in the field of marine environmental protection.

A PAM–PAA hydrogel electrolyte integrates electrolyte retention, Zn interfacial regulation and mechanical adaptability, enabling flexible Zn–air batteries with stable high-current operation.

Photocatalytic water splitting for clean energy production holds significant practical potential in addressing the global energy crisis. However, the oxygen evolution reaction (OER) remains the primary bottleneck in overall efficiency due to its kinetically sluggish and complex four-electron transfer process. Bi4Ti3O12 theoretically meets the reaction conditions of OER because of its high valence band value and unique layered structure formed by alternately stacking perovskite layers [Bi2Ti3O10](2-) and bismuth oxide layers [Bi2O2](2)(+). However, its application in OER is limited due to its unsatisfactory charge distribution, poor separation efficiency, and low selectivity for O-2. Therefore, the Ag-Bi4Ti3O12 composite photocatalyst was prepared by photodeposition. The Schottky barrier between the n-type semiconductor Bi4Ti3O12 and the noble metal Ag can be used as an effective charge transfer channel. This can alter the surface charge distribution and space charge separation efficiency of Bi4Ti3O12, prevent the selective generation of hydroxyl radicals, further enhance its product selectivity to O-2, and raise Bi4Ti3O12's OER efficiency. The results show that the OER rate of Bi4Ti3O12 after Ag loading is obviously improved, which is about twice that of unmodified Bi4Ti3O12. The research results of this work will provide research ideas for the design of efficient OER catalysts.

An S-scheme heterojunction NiFe-MOF/Bi4O5Br2 (NFM/BOB) photocatalytic material was successfully synthesized via a hydrothermal method. The interfacial electric field (IEF) between the two components effectively facilitates the separation and transfer of photogenerated charge carriers. Through synergy with peroxymonosulfate (PMS), the NFM/BOB-3 %/PMS system maintained consistently high degradation efficiency across a wide pH range (pH=1 similar to 13), overcoming the strong pH dependency inherent in conventional catalytic systems. Furthermore, the synergistic coefficient between NFM/BOB-3 % and PMS was calculated as 2.96, confirming that their synergistic interaction significantly enhances degradation efficiency. A 10 h continuous-flow degradation experiment demonstrated stable degradation efficiency consistently maintained at approximately 95 %, validating both the high catalytic performance and robust stability of NFM/BOB-3 %. Electrochemical tests and work function calculations, the electron transfer mechanism between NiFe-MOF and Bi4O5Br2 was confirmed. Quenching experiments identified the primary reactive species in the order: O-1(2) > h(+)> OH > O-2(-) > SO4-. This study provides valuable insights for antibiotic remediation in complex aquatic environments.

Anatase TiO2 (A-TiO2) is regarded as one of the best photocatalysts for hydrogen production technology. However, it presents a formidable challenge for application in seawater splitting process, because of the poisoning effect induced by Cl-oxidation. Herein, a simple strategy of incorporating microcrystalline cellulose (MCC) into the photocatalytic seawater splitting system is proposed to address this issue. The addition of MCC can prevent the Cl- oxidation, inducing the Pt/A-TiO2 photocatalyst to exhibit a superior stability and a higher H2 production rate of 113.5 mu mol g- 1 h- 1. In contrast, without MCC, it only exhibits an H2 evolution rate of 36.2 mu mol g- 1 h- 1 and experiences an obvious decline to 16.6 mu mol g- 1 h- 1 during the subsequent cycle experiments. These findings demonstrate the feasibility to protect photocatalyst from Cl- oxidation corrosion by applying MCC, which is expected to achieve a stable photocatalytic hydrogen production in seawater.

Deactivating the concentration of marine microorganisms is suitable and proper for ballast water treatment. In here, a promising strategy has been presented to create massive oxygen vacancies synergistic with metallic Bi nanoparticles on ZnWO4 for inactivating marine bacteria in seawater, demonstrating that the paramount incorporation of metallic Bi nanoparticles and 2BZWO (Bi/ZnWO4) samples exhibits superior photocatalytic sterilization, in which the sterilization efficiency of 2BZWO is 2.83 times that of pure ZnWO4. The co-incorporation of metallic Bi nanoparticles and oxygen vacancies significantly enhanced the absorption of visible light and enrichment of the photogenerated electrons, promoting the separation of charge carriers. Moreover, first-principles calculations demonstrate that the coeffect of metallic Bi nanoparticles and oxygen vacancies guided the reconfiguration of the active sites and electrons flowing direction. Results from this study provide a creative strategy on controllable Bi/ZnWO4 synthesis to manipulate the photocatalytic inactivation of marine bacteria.

Addressing the issues of hazardous organisms and their facilitated diffusion is crucial for ensuring the long-term viability of maritime industries and safeguarding marine ecosystems. In this study, a p-n heterostructure scheme of CuBi2O4@CeO2 photocatalysts was established by a facile wet chemical in-situ deposition for marine bacteria inactivation, experimental results demonstrate that the introduction of CeO2 enhances overall bacterial sterilization efficacy, 15%CuBi2O4@CeO2 exhibits the priority sterilization efficiency about 3.3, and 2.8 times to pure CeO2 and pure CuBi2O4, respectively, and the inactivation effects of center dot OH is superior to the other mainstream active species. Moreover, incorporating CeO2 film on the surface of CuBi2O4 contributes to the selectively production of active species, shorten the electron transfer distance, and improves light response efficiency which derive from the innovative heterostructure design, a rational connection bridge between CeO2 and CuBi2O4 based on the band structure positioning, facilitates faster separation and transfer of photo-generated carriers while simultaneously suppressing charge carriers recombination. This paper offers an methodology and construction of harmless heterostructure photocatalysts for ballast water treatment and fosters a deeper understanding of the underlying photocatalytic mechanisms.

Understanding and leveraging non-reactive species in natural environments to modulate the active centers of geminal-atom catalysts (GACs) is crucial for enhancing their catalytic performance. Here, we develop a two-coordinated copper geminal-atom catalyst and reveal that the ubiquitous yet inert carbonate ions (CO3 2-) in seawater dynamically reorganize the coordination environment of active copper sites, thereby enhancing photo-Fenton reactivity. Control experiments, in situ spectroscopy and theoretical modeling demonstrate that CO3 2- induces reversible coordination transformations that modulate the electronic structure and facilitate interfacial charge transfer, resulting in a 17-fold increase in hydroxyl radical production. This effect enables efficient degradation of diverse marine pollutants, including effective Chlorella decomposition under natural sunlight. Life-cycle and technoeconomic assessments further demonstrate the environmental benefits and economic feasibility of this approach. Overall, this work establishes a generalizable strategy for active geminal-atom catalysts via environmentally abundant species, offering mechanistic insights and scalable pathways toward large-scale and sustainable aquatic pollution remediation.

The rapid elimination of antibiotics across the entire pH represents a pressing environmental challenge. In this work, an S-type heterojunction named CoFe-LDH/Bi4O5Br2 was synthesized using a straightforward hydro- thermal method. The results revealed that the CoFe-LDH/Bi4O5Br2-3 % (CFL/BOB-3 %), when synergized with 0.3 g/L peroxymonosulfate (PMS), could effectively degrade 80 % of a high-concentration (70 ppm) tetracycline solution (TC) within just 10 min. Moreover, the system maintained a relatively stable degradation rate across the pH range of 1 to 13, signifying the system's robust resilience to pH fluctuations and its suitability for use across the entire pH range. Subsequently, the degradation rate of TC stabilized at approximately 96 % for 10 h during the flow degradation experiment, signifying the catalyst's exceptional stability. Additionally, quenching experiments revealed that the main active species were high-valent metal-oxo species (HVMSs) and 1O2. Further investigations revealed that the enhancement in performance could be ascribed to the swift separation and S-type transfer of photogenerated carriers caused by the interfacial electric field (IEF). The study could inspire the further design of S-type photocatalysts with giant IEF for PMS activation.

The inherent electron-hole recombination, low light-absorption capacity and poor selectivity of photocatalysts hinder the production efficiency of hydrogen peroxide (H2O2), necessitating the development of a catalyst with high catalytic activity. In this study, a supramolecular self-assembly method was employed to prepare 4-aminobenzonitrile-modified carbon nitride (Abz-CN). The incorporation of the cyano group rendered the charge distribution of Abz-CN inhomogeneous, leading to an increased dipole moment. This enhancement facilitated the separation and migration of photoinduced carriers. Additionally, density functional theory (DFT) calculations revealed that Abz-CN had a higher propensity for oxygen adsorption and the formation of *OOH intermediates compared to carbon nitride (BCN). The H2O2 generation rate of Abz-CN reached 3866 mu mol & sdot;g(- 1)& sdot;h(- 1 )(under a 180 W xenon lamp, lambda > 400 nm), which was 5.2 times that of BCN. Furthermore, the mechanism of Abz-CN followed a sequential two-step single-electron oxygen reduction process. This study showcases an innovative approach for bolstering the efficiency of photocatalytic H2O2 generation.

Compared to conventional aqueous metal-air batteries, seawater batteries provide a promising strategy for the sustainable energy conversion and storage systems. However, the intricate ionic environment of seawater, in particular, Cl significantly restraint the oxygen reduction reaction (ORR) activity of the catalysts. Herein, mesoporous carbon materials with abundant oxygen-containing functional groups were simply fabricated as the cost-effective catalysts from the biowaste Ginkgo biloba, exhibiting prominent stability and ORR activity with a 4e path selectivity up to 92 % in seawater electrolyte. Structure characterization and ORR experimental results indicated the ORR performance was significantly modulated by the C-O-C in carbon matrix, and the synergistic of C-O-C and N-containing configuration may further enhance the dissociation of O-O of *OOH, resulting in an optimized 4e path selectivity. Additionally, the Ginkgo biloba derived catalysts displayed an overpotential of 580 mV for at 10 mA/cm2 more negative than that of the previously reported commercial Ir/C in seawater electrolyte. This study highlights the synthesis of sustainable and cost-effective catalysts for seawater batteries, offering a strategy for designing metal-free catalysts of seawater battery, and promoting the advancement of sustainable energy conversion and storage technologies.

To address the issue of high electron–hole recombination rate in conventional catalysts used for the photocatalytic treatment of ballast water, this work designed and synthesized a Bi2Sn2O7/BiOCl heterojunction photocatalyst via a simple hydrothermal method. After 30 min of simulated sunlight irradiation, it exhibited outstanding inactivation efficiency against marine bacteria. The Bi2Sn2O7/BiOCl-0.6 heterojunction achieved an inactivation efficiency of up to 92

Understanding and leveraging non-reactive species in natural environments to modulate the active centers of geminal-atom catalysts (GACs) is crucial for enhancing their catalytic performance. In this study, we present a two-coordinated geminal Cu atomic catalyst and, for the first time, uncover the mechanism by which dynamic metal second coordination shell and non-reactive species boost its photo-Fenton activity. This breakthrough enables the efficient removal of pollutants such as marine microorganisms, oils, and microplastics. Through experimental studies, operando X-ray absorption spectroscopy, and theoretical analyses, we demonstrate that the dynamic coordination environment promotes synergistic dual-atom interactions, and the second coordination shell influences the significant orbital overlap between the central metal and the delocalized ligand orbitals, enabling direct electron transfer. Additionally, the dynamic coordination of GACs induces a local spin transition, which lowers the reaction barrier through spin-crossover at the active site. This, in turn, reduces the spin-flip barrier for forming the singlet-state *OOH and OH-, thereby accelerating spin non-conservation reactions. The interactions between CO32- ions and adjacent Cu sites significantly alter the electronic structure of the catalytic centers. These modifications enhance charge transfer kinetics, leading to a remarkable 17-fold increase in hydroxyl radical production. This innovative approach—utilizing non-reactive species to amplify the photo-Fenton activity of Cu GACs—offers a constructive solution for environmental remediation in complex matrices and provides valuable guidance for designing high-performance catalysts tailored to challenging environmental conditions.

Producing hydrogen from solar energy and seawater via photoelectrochemical (PEC) technology is an attractive approach for sustainable energy conversion. However, there are still huge challenges due to the unfavorable chlorine evolution reaction (CER). Herein, a strategy was proposed to inhibit the CER via constructing an S, N codoped carbon dots (S, N-CDs) splicing layer (SNCL) on a TiO2 nanoarray (NA) photoanode. The produced SNCL 5/TiO2 NA photoanode obtained a CER faradaic efficiency (FE) of 35.6 %, far below that of the original TiO2 NA sample (88.3 %). Moreover, it can maintain its photocurrent density, exhibiting a corrosion resistance under seawater conditions. Further enhancing the sulfur content within SNCL, the FE (CER) could be further reduced to merely 19.5 %. Meticulous characterization and simulation reveal that the SNCL can isolate Cl ions and the TiO2 NA catalyst, giving rise to inhibition of the harmful CER. This work not only provides a potential anode material for PEC seawater splitting, but also offers a directive for developing PEC catalysts with CER-inhibiting performance in subsequent research.