The development of simple, cost-effective, and reliable sensing strategies for perfluorooctanoic acid (PFOA) is imperative for environmental safety. In this work, a novel label-and probe-free electrochemical sensor is constructed by integrating a highly redox-active ternary FeCoNi Prussian blue analogues (PBAs) core with a molecularly imprinted polypyrrole (mPPy) shell. The ternary FeCoNi PBAs core acts as a robust internal signal reporter, exhibiting more intense and well-defined intrinsic redox activity compared to its binary (FeCo-, FeNi-PBAs) counterparts, owing to synergistic mixed-valence interactions and richer redox chemistry. The conformal mPPy shell plays a triple role: (1) enhancing the overall conductivity, (2) protecting the PBAs core against dissolution, and (3) enabling the specific capture of PFOA. The binding of insulating and hydrophobic PFOA molecules within the imprinted cavities impedes electron/ion transfer to the PBAs core, causing a measurable decrease in its oxidation peak current. This allows for the quantitative determination of PFOA without requiring any external labels or probes. The sensor achieves a wide linear range (1.0 pM-5.0 nM), a low detection limit (0.031 pM), excellent selectivity, satisfactory reproducibility (RSD < 1.57%) and long-term stability (drift<1.28% after 30 days), good reusability (similar to 96.8% signal retention after five regeneration cycles), and reliable performance in actual environmental water matrices. The study not only delivers a high-performance PFOA sensor but also highlights the advantage of ternary PBAs for building sensitive, direct signaltransduction platforms targeting non-electroactive pollutants.

Diverse water treatment technologies are widely applied to manage water quality, with ubiquitous hydraulic energy remaining. Emerging hydraulic pressure–electricity conversion, along with its in situ utilization, provides a promising strategy for addressing common challenges in water treatment, which is convenient, efficient, and practical. This innovative concept has garnered extensive interest and has achieved exciting progress over the past decade. Piezoelectricity, which induces charges via mechanical deformation, serves as a direct hydraulic energy harvesting mechanism to achieve force–electricity conversion, opening new avenues for innovating traditional water treatment technology while compensating for its shortcomings. However, such in situ hydraulic–electricity coupling is still in its early evolutionary stage and requires thorough investigation to determine future development directions. With this in mind, we discuss hydraulic piezoelectricity as a means of addressing common challenges in water treatment technologies, with a focus on representative membrane fouling, catalytic reactions, and sludge dewatering. Then, we further explore other emerging hydraulic-based technologies, such as hydrovoltaics, solid–liquid triboelectricity, and other energy methods, such as thermal energy, to expand the paradigm and scenarios of in situ electricity advancements in the water treatment process.

The underdeveloped CO2 photo-reduction solid-gas mode still relies on precious metals to produce CH4. Finetuned ingenious structure and morphology with nonprecious metal can enable better performance with lower cost. We have synthesized and modified a TiO2 with a three-stage cavity and a three-shelled layer, loaded with In2S3 flakes only on the outermost layer. The porous hollow multi-shelled structure can give a sequence of gas diffusion from inside to outside or vice versa. Due to the confinement effect, products generated by the core can only be transferred from the inside to the outside in a unidirectional manner. The In2S3/TiO2 catalysts exhibited high performance comparable to that of conventional noble metal catalysts (e.g., Au-Ag-Pt), with a selectivity of up to 98.28 % for CH4 and a rate of 296.87 mu mol & sdot;g-1 & sdot;h-1 without using any co-catalyst or sacrificial agent. Systematic fundamental characterization, as well as in situ characterization and DFT calculations show that homo-junctions consisting of two crystalline phases of TiO2 contribute to the production of more *Hads and *CO. Desorbed CO can be captured and catalyzed by the outer shell In2S3/TiO2 S-scheme heterojunction during diffusion for methanation via formaldehyde intermediate. A series of photoelectrochemical characterizations also confirms that the In2S3/TiO2 hetero-junction improves light absorption and charge separation efficiency. This work provides insight into the future rational design of hollow semiconductors for artificial photosynthesis systems and selective solar fuel production.

Precise control over nanostructured scaffolds, such as hollow multi-shelled structures engineered to incorporate both homo- and heterojunctions, has been far less frequently mimicked. This study developed a sacrificial template method to synthesize hollow TiO2 microspheres with a controlled number of shells and a closed, thin exterior shell. The rutile/anatase phases within the TiO2 scaffold were regulated to form an optimized homojunction, followed by the in-situ growth of In2S3 nanoplates to construct a heterojunction. Detailed investigations illustrated that the coupling of homo- and heterojunctions established a type-Ⅱ configuration with well-aligned band-edge levels. Furthermore, the increased charge carrier density, rapid charge migration kinetics, and large electrochemically active surface area collectively contributed to outstanding photoelectrochemical (PEC) performance. As a result, the final composite served as an effective matrix to fabricate a PEC sensing platform for cell assays, with a limit of detection of 117 mL-1 (S/N = 3). A novel strategy was proposed for evaluating epidermal growth factor receptor (EGFR) on the surface of different cell lines, further achieving actual applications in drug screening and physiological monitoring. This study not only explores PEC substrates by precisely engineering hollow architecture and energy band configurations, but also develops promising strategies for cytosensing and protein subtype assessment.

In biomedical diagnostics, endogenous oxygen-mediated electrochemiluminescence (ECL) systems hold promise for avoiding toxic exogenous coreactants but are limited by sluggish oxygen reduction reaction (ORR) kinetics, a long-standing, cross-disciplinary challenge hindering ECL progress toward ultrasensitivity and sustainability. Herein, Pt-Ni alloy coral-like nanoclusters are prepared by tuning Pt/Ni precursor ratio and glucose template concentration. Acid etching created a thin Pt skin overlying the residual Pt-Ni core, introducing >1.78% interfacial compressive strain. This hierarchical architecture, synergizing ligand and strain effects, enables a four-electron ORR (49.56 mV dec(-1) Tafel slope) that outperforms commercial Pt/C. Theoretical calculations confirmed that this design modulates electron distribution, downshifting the d-band center and weakening oxygen adsorption energy, thereby boosting ORR activity. Using dissolved oxygen as the coreactant, this Pt-based catalyst sensitizes the ECL emission of graphitic carbon nitride nanoplates by 14.5-fold while maintaining stability for >10 min, affording an ECL platform for breast cancer diagnosis via HER2 proteins and BT-474 cells. It can discriminate HER2-positive samples from negative ones, monitor HER2 expression across different cell lines, and dynamically track expression changes. This work not only overcomes ORR bottlenecks but also enables high-performance, eco-friendly ECL catalysts, further advancing the clinical translation of endogenous oxygen-mediated ECL in precision oncology.

An anatase/TiO2(B) homojunction loaded with Au nanoparticles was synthesized, achieving a C2H6 yield rate of 170 mu mol g-1 h-1 in a flow photoreactor. The homojunction reduces TiO2(B)'s strong oxidative ability, offering a more moderate environment for methane dehydrogenation, while Au aids in charge mitigation and methyl radical coupling. The catalyst highlights homojunction engineering and a ternary synergistic effect in photocatalytic CH4 coupling.

Electrocatalytic nitrate reduction sustainably produces ammonia and alleviates water pollution, yet is still challenging due to the kinetic mismatch and hydrogen evolution competition. Cu/Cu 2 O heterojunction is proven effective to break the rate-determining NO 3 − -to-NO 2 − step for efficient NH 3 conversion, while it is unstable due to electrochemical reconstruction. Here we report a programmable pulsed electrolysis strategy to achieve reliable Cu/Cu 2 O structure, where Cu is oxidized to CuO during oxidation pulse, then regenerating Cu/Cu 2 O upon reduction. Alloying with Ni further modulates hydrogen adsorption, which transfers from Ni/Ni(OH) 2 to N-containing intermediates on Cu/Cu 2 O, promoting NH 3 formation with a high NO 3 − -to-NH 3 Faraday efficiency (88.0±1.6 %, pH 12) and NH 3 yield rate (583.6±2.4 μmol cm −2  h −1 ) under optimal pulsed conditions. This work provides new insights to in situ electrochemically regulate catalysts for NO 3 − -to-NH 3 conversion.

Research and development of efficient and practical new wastewater treatment technologies, particularly for the efficient removal of persistent toxic and hazardous pollutants, has become a cutting-edge and high-priority issue in the field of environmental science. Photocatalysis, as an emerging advanced oxidation technology, offers advantages such as mild reaction conditions, utilization of solar energy, wide applicability, and absence of secondary pollution, making it highly promising for wastewater treatment applications. The key to photocatalysis lies in catalyst design, and hollow multistage materials represent a special structure with great potential in the field of photocatalysis. In this study, hollow multishell layers of titanium dioxide with varying numbers of layers were synthesized using a sequential template method, and Z-scheme heterostructured composite catalysts with different CuInS2@3S-TiO2 ratios were modified and prepared using a hydrothermal method. A photocatalytic system dominated by the photoanode was constructed for the degradation of levofloxacin (LEV), and a series of degradation parameters were optimized to investigate the degradation mechanism of the system. Experimental results confirmed the pathways of electron transfer through XPS, Mott-Schottky, and other tests. It was also confirmed that the heterostructure composed of CuInS2@3S-TiO2 extended the light absorption range, enhanced the photocurrent density, and promoted the separation of photogenerated electrons and holes. The photovoltaic electrodes also demonstrated good cycling stability during practical use. Quenching experiments confirmed the active substance species and dominant active species. Control experiments further confirmed the advantages of the structure and the rationality of the system design. The combination of structural engineering and heterojunction design in this study achieved regulation of both degradation efficiency and mineralization efficiency. Additionally, the possible catalytic mechanisms for achieving cascade reactions at the spatial interface were explored. The results showed that the degradation efficiency of LEV by CuInS2(5%)@3S-TiO2 could reach 93.7% within 40 minutes under the optimized conditions of 7.5 mA·cm−2, unadjusted pH (5.5), and 25 ℃.

General strategies for metal aerogel synthesis, including single-metal, transition-metal doped, multi-metal-doped, and nano-metal-doped carbon aerogel are described. In addition, the latest applications of several of the above-mentioned metal aerogels in electrocatalytic CO2 reduction are discussed. Finally, considering the possibility of future applications of electrocatalytic CO2 reduction technology, a vision for industrialization and directions that can be optimized are proposed.

The energy-induced peroxydisulfate (PDS) activation is a green and effective approach for pollutant degradation, while the huge energy consumption would significantly increase the cost of wastewater treatment. In this study, by taking carbon nanotubes (CNTs) membrane as the light to heat (LTH) conversion materials, we developed a photothermal PDS activation process for degradation of organic contaminants in a flow-by reactor, with hydroxyl radicals (•OH) and sulfate radicals (SO4•-) as the main reactive species. This system has excellent in-situ LTH conversion performance and heat transfer ability. As a result, various pollutants are degraded with an efficiency higher than 90%. More importantly, the LTH device exhibits satisfying stability and could be used for pollutant (i.e., methyl orange (MO)) removal under solar irradiation. In addition, some important factors (i.e., irradiation distance, residence time, solution pH, and PDS dosage) that might significantly influence the removal efficiency of pollutants are optimized. This work provides a novel perspective for the activation of PDS via CNTs as photothermal materials for pollutant degradation with a flow-by reactor.

Designing metal-metal oxide heteronanostructures with synergistic and superior activities (unattainable in the case of a single entity) is of great interest for a wide range of technological applications. Traditional synthetic strategies typically require reducing agents, stabilizing ligands, or high temperature reductive treatment to produce oxide-supported metals. Herein, a facile noble metal deposition strategy is developed to produce silver, gold, and platinum nanocrystals on the surface of hollow mesoporous cerium oxide nanospheres without any pretreatment. Unlike the galvanic replacement reaction, the developed protocol employs the innate reductive potential of CeO2 to produce a high density of ultrafine noble metal nanocrystals homogeneously immobilized onto the surface of CeO2 nanospheres. The multienzyme-like activities (i.e., superoxide dismutase-like and catalase-like) of CeO2@metal nanostructures, originating from CeO2 and metal nanoparticles, were effectively utilized for anti-inflammatory therapies in two in vivo models. This oxygen vacancy-mediated reduction strategy can be generalized to produce diverse metal-metal oxide nanostructures for a wide range of applications.

Currently, the excessive consumption of fossil fuels is accompanied by massive emissions of CO2 , leading to severe energy shortages and intensified global warming. It is of great significance to develop and use renewable clean energy while reducing the concentration of CO2 in the atmosphere. Photocatalytic technology is a promising strategy for carbon dioxide conversion. Clearly, the achievement of the above goals largely depends on the design and construction of catalysts. This review is mainly focused on the application of 2D materials for photocatalytic CO2 reduction. The contribution of synthetic strategies to their structure and performance is emphasized. Finally, the current challenges, and prospects of 2D materials for photoreduction of CO2 with high efficiency, even for practical applications are discussed. It is hoped that this review can provide some guidance for the rational design, controllable synthesis of 2D materials, and their application for efficient photocatalytic CO2 reduction.

Simultaneous treatment of CO2 and H2S by photocatalytic technology is of great significance in mitigating the greenhouse effect and environmental hazards, while producing valuable solar fuels at the same time. In this study, well‐defined CdS/TiO2:Cu hollow spheres with highly dispersed heterointerfaces are successfully constructed for photoreduction of CO2 in presence of in situ generated H2S. Benefiting from the consumption of photo‐generated holes (h+) and large production of protons by H2S decomposition, the generation rates of CO (781.3 µmol·g−1∙h−1, accounting for 94.9 v/v% of CO2 reduction products) and H2 (5875.1 µmol·g−1∙h−1) increased significantly, which are 1.4 and 68.9 times higher than that of the system without H2S, respectively. Moreover, the remediation of photocorroded CdS by H2S prolonged the service life of the heterojunction, and maintained a CO generation rate of 96.8% after 4 cycles with or without H2S. Notably, as a potential syngas production strategy, by adjusting the initial concentration of Na2S, the ratio of CO and H2 is controlled from 1.07 to 7.21 to fulfill the demands of different chemical synthesis. This strategy opens up a new horizon for the combination of energy photocatalysis and environmental photocatalysis, which has great research and application prospects.

Nanozymes are nanomaterials with enzyme-like activities, which have been developed for inflammatory disease therapy by reactive oxygen species (ROS) scavenging. The application of nanozymes in ulcerative colitis (UC) treatment not only inherits the merits of small molecular antioxidants (e.g., 5-aminosalicylic acid) to scavenge ROS but also achieves catalytic recycle instead of stoichiometric consumption. However, current therapies usually ignore the repair of mucosa, the first line of defense, whose damage increases the risk of infections. Herein, a multifunctional nanozyme hydrogel is designed and verified both as an ROS scavenger and a mucosal healing enhancer for UC therapy. The chitosan-coated CeO2 nanozyme (CCNZ) not only possesses excellent ROS-scavenging ability but also exhibits satisfactory antibacterial capacity. After gelation with alginate, the optimized CCNZ1:Alg1.5 nanozyme hydrogel exhibits multiple functions, including inflamed site targeting, supporting cell growth, ROS scavenging, and antibacterial activity, which alleviates UC better than a clinical medication 5-aminosalicylic acid by even a single-dose treatment. This study reveals that a nanozyme providing mucosal healing is promising for UC therapy with excellent potential for clinical application and enriches the nanozyme research of treatment for diseases.

In order to overcome the sluggish kinetics of the redox conversion between Fe3+ and Fe2+ in Fenton process, we established a novel electro-Fenton system based on GO-Fe3O4 cathode and tannic acid (TA) for the efficient degradation of p-nitrophenol (PNP). Under the optimal degradation parameters (including the initial PNP concentration of 20 mg L-1, pH = 5, current density of 30 mA cm(-2) and feeding ratio of PNP: TA = 1:2), the TA reinforced GO-Fe3O4 electro-Fenton system exhibited the removal rate of PNP over 90.1 +/- 0.2%, the COD removal rate of 69.5 +/- 0.84% and satisfactory reusability (with the removal rate of -80% after 5 recycles). The excellent degradation performance of the proposed TA reinforced GO-Fe3O4 electro-Fenton system was partly attributed to the optimized morphology (with the particle size of Fe3O4 reduced to tens of nanometers, pore size decreased by -80% and pore volume increased by 24.3 times) and larger specific surface area (increased by 72.7 times) after compositing GO with Fe3O4 , which exposed more active sites. In return, the electron transfer process, the two-electron oxygen reduction reaction (ORR) and the degradation efficiency were promoted in the cooperation of GO and Fe3O4 . Moreover, the incorporated TA would form a TA-Fe(III) complex to promote the reduction reaction from Fe3+ to Fe2+, which strengthened the self-circulation of Fe2+ and Fe3+ and indirectly enhanced the conversion of H2O2 to ROS to decompose PNP into smaller organic fragments or mineralize into CO2, H2O, NO2- or NO3-, etc. Obviously, the incorporation of TA provided a promising strategy to improve the electro-Fenton efficiency and realize the efficient removal of PNP in wastewater.

By employing a conjugated amine-functionalized dicarboxylic ligand (H2L = 2,2'-diamino-4,4'-stilbenedicarboxylic acid, H2SDCA-NH2), we have successfully synthesized and characterized a porous and visible light responsive zirconium metal-organic framework ([Zr6O4(OH)4(L)6]·8DMF, denoted as Zr-SDCA-NH2). This Zr-MOF showed good chemical stability and broad visible light absorption with an absorption edge at about 600 nm. When used as a photocatalyst, Zr-SDCA-NH2 exhibits visible-light activity for CO2 reduction with a formate formation rate of 96.2 μmol h-1 mmolMOF-1, which is higher than the series of reported amine-functionalized Zr-MOFs. Mott-Schottky measurements, photoluminescence study and photocatalytic experiments demonstrated that the Zr6 oxo cluster through the LMCT process and the organic ligand both contributed to the CO2 photoreduction. This study indicates that the combination of amino groups and highly conjugated molecules is a feasible and simple strategy to extend light absorption of the organic ligand, which is beneficial for designing a visible light responsive MOF photocatalyst.