Foams are dispersions of gas in a liquid, consisting of multiple closely packed air bubbles. The bulk elasticity of foams is positively correlated with surface elasticity and can be tuned by controlling surface mechanical properties. We studied surface rheology of air-water interfaces stabilized by hemp proteins and their complexes with pectin using small and large amplitude oscillatory shear or dilatation (i.e., SAOS/LAOS and SAOD/LAOD). These stabilizers produce air-water interfaces with a wide range of interfacial stiffness. Bulk rheology of foams formed with these stabilizers was studied using small and large amplitude oscillatory shear (SAOS and LAOS) and continuous shear rheological tests. Albumin-pectin complexes formed the stiffest air-water interfaces and the most stable foams, followed by globulin-pectin complexes and hemp globulins, while hemp albumin formed the weakest air-water interface and thus the most unstable foams. The relationship between surface rheology (Gi' and Ed') and bulk foam rheology (G') was explored and correlations between several parameters were observed both in the linear and nonlinear viscoelastic regimes. In the latter regime, the relationship between interfacial and bulk rheological properties is rarely studied, and for many systems not known. Finally, good agreement between experimental results for the bulk shear modulus in the linear regime and the prediction of a physical model was found, showing the broad applicability of this model across a wide range of stabilizers, and across systems (i.e., air-water and oil-water based). These insights allow for a more efficient control of bulk rheological properties of foam-based materials, both at small and large deformations, by tuning the (nonlinear) 2D rheology of their air-water interfaces.
The HLD-NAC (Hydrophilic-Lipophilic Difference - Net Average Curvature) equation of state is a powerful semi-empirical framework used to predict the phase behavior, solubilization, and interfacial properties of surfactant-oil-water (SOW) systems it is based on the assumption of a normalized curvature for an idealized microemulsion, represented as the coexistence of two fictitious phases: water droplets dispersed in oil and oil droplets dispersed in water. The characteristic sizes of these droplets are combined into two quantities: the net-curvature Hn and the average-curvature Ha. The microemulsion structure is more accurately described as a random surface separating oil and water domains. This representation can be effectively framed in terms of Gaussian random fields, for which expressions for the surface-averaged mean and Gaussian curvatures, 〈H〉 and 〈K〉, are available. On this basis, we demonstrate that 〈H〉 has the same functional form as the net curvature Hn in the NAC model. Furthermore, we show that the empirical HLD parameter corresponds to 〈H〉 normalized by the surfactant length, thereby enabling a direct prediction of the microemulsion composition at the emulsification failure from HLD. The resulting predictions show excellent agreement with experimental data. The possibility to evaluate the preferred mean and Gaussian curvature and compare it with the HLD equation of state opens the way to further in-depth analysis about the link between the film curvature and the parameters entering the HLD-NAC (viz. chemical structure of oil and surfactant, temperature and the ionic strength).
The engineering of the nanozyme interface is crucial for manipulating their catalytic efficacy, yet achieving this through chirality modulation still remains a significant challenge. In this work, a chirality-driven interface engineering strategy by constructing chiral L/D‑copper oxide hierarchical architectures (L/D-CuO) via a facile one-step wet-chemistry method using enantiomeric cysteine ligands. The resulting hierarchical architectures feature flower-like architectures, and more importantly exhibit intense and chiroptical activity, unambiguously confirming the successful creation of a tailored chiral interface. Steady-state kinetic analyses revealed that the engineered chiral interface significantly augmented the peroxidase-like (POD-like) activity. The L-CuO demonstrated a lower Michaelis-Menten constant (Km = 1.003 mM) and a higher maximal reaction rate (Vm = 0.0252 μM·s-1) compared to achiral CuO (Km = 1.38 mM, Vm = 0.0185 μM·s-1), indicating enhanced substrate affinity and catalytic efficiency at the interface. This augmented interfacial catalysis was effectively translated into potent antibacterial action. The L-CuO achieved a bacterial inhibition rate reaching 90.2% against E. coli and 93.1% against S. aureus, compared with only 59.3% for E. coli and 66.9% for S. aureus antibacterial efficacy for achiral CuO. In practical fruit preservation, the chiral hierarchical architectures effectively functioned as an interfacial antimicrobial coating, significantly preserving fruit quality by inhibiting surface microbial spoilage. This work highlights the profound impact of chirality-driven interface engineering on nanozyme functionality and provides a foundational strategy for designing advanced interfacial catalysts for antibacterial and other biomedical applications.
Resonant thermal capillary fluctuations (RTCFs) of bubble surfaces encode the mechanical response of fluid interfaces at the nanoscale, thereby providing direct access to their nanorheology. The presence of ions or surfactants is expected to modify the mechanical properties of the air/liquid interfaces in ways that are directly linked to bulk and interfacial rheology. Sessile air bubbles were immersed in aqueous solutions of controlled composition, including pure water, salt solutions, and surfactant solutions. Thermal oscillations of the bubble surface were probed through the deflection of an atomic force microscope (AFM) cantilever gently contacting the bubble apex. The resulting power spectral densities exhibited multiple resonance peaks corresponding to different vibrational modes of the bubble. By fitting these peaks, mode-specific resonance frequencies and damping coefficients were extracted. Measurements were performed as functions of salt or surfactant concentration to quantify how solution composition alters interfacial mechanical properties and thereby determine the associated rheological parameters. In salt solutions, the resonance frequency provides a direct measurement of the surface tension, while the damping coefficient determines the liquid viscosity. In surfactant solutions, the moduli obtained from damping coefficient measurements as a function of surfactant concentration agree with the expected Gibbs elasticity, a quantity generally inaccessible to conventional low-frequency techniques due to the dominant role of bulk surfactant diffusion. This methodology therefore establishes a high-resolution tool for investigating interfacial rheology at the nanoscale and at high frequencies.
Saliva is essential for oral lubrication and is influenced by interactions with foods, beverages and pharmaceuticals and their components. We hypothesize that increasing protein concentration increases protein adsorption and therefore reduces measured friction coefficient on the saliva coated tribopair. In this study, we employed our dynamic tribological protocol (DTP) to measure friction coefficient of model bovine serum albumin (BSA) solutions on ex vivo human whole saliva (HWS), saliva pellicle and proline-rich protein (PRP) components of the salivary film. This approach advances current methods that overlook saliva's complexity by testing on bare polydimethylsiloxane (PDMS) surfaces or using whole saliva. Quartz crystal microbalance with dissipation (QCM-D) monitored the mass and viscoelastic properties of these adsorbed layers. We find that BSA concentrations >5.4 mg/ml correlate with decreased friction coefficients across bare PDMS and PDMS coated with the salivary pellicle and PRP layers, suggesting increased protein adsorption. This contrasts with friction measured with whole saliva, which showed no significant difference between samples from 0.6 to 10.4 mg/ml BSA concentration. QCM-D revealed substantial changes in the mass and viscoelastic properties of the adsorbed layers, highlighting a concentration-dependent interaction between BSA and salivary proteins. These interactions suggest that BSA modifies the structural properties and enhances lubrication on the saliva pellicle, impacting oral processing of foods, beverages and pharmaceuticals. These findings expand understanding of salivary lubrication mechanisms and provide an enhanced method for investigating saliva-protein interactions. This offers insight into biophysical changes at oral surfaces during food and pharmaceutical intake, informing the design of products optimized for delivery, mouthfeel, and consumer satisfaction.
Precise control of motion is fundamental to living organisms, enabling the execution of complex behaviours. Although previous supramolecular colloidal motors driven by asymmetrically assembled FOF1-ATP synthase have achieved biomimetic motion, their homogeneous surface properties and random enzyme distribution hinder directional propulsion and complicate mechanistic analysis. Here, we present Janus rotary biomolecular motor-powered supramolecular (RBMS) colloidal motors fabricated via a controlled assembly approach. These motors feature a polyethylene glycol (PEG)-gold hemispherical shell on one hemisphere and chromatophore vesicles harboring FOF1-ATP synthase on the opposite hemisphere. This asymmetric architecture enables clear distinction of movement direction and integrates multiple functions, including directional motion, anti-biofouling capability, and on-demand ATP synthesis, storage, and release. A sustained and tunable transmembrane proton gradient, generated by a glucose oxidase (GOx)-catalyzed reaction, drives both self-propulsion and internal ATP production. The motors also exhibit positive chemotaxis and allow spatiotemporally controlled ATP release via photothermal effect of the gold layer. By combining directed motility with energy conversion and programmable cargo delivery, this system provides a versatile biomimetic platform for precision biomedical applications.
Ferulic acid (FA), a natural bioactive compound, faces severe limitations in health-promoting applications due to its poor water solubility and low bioavailability. Different from physical encapsulation of FA in hydrogels, this study develops sodium deoxycholate (NaDC)-FA supramolecular hydrogels through direct assembly of NaDC with FA. The prepared NaDC-FA hydrogels contain 20-80 mM FA, which are about 5-20 times FA amount in the saturated solution. Experimental studies of phase behavior, scanning electron microscopy, small-angle X-ray diffraction, fourier transform infrared and Raman spectra, together with computational simulation reveal that as FA concentration increases from 20 mM to 30 mM, the flexible nanofibers are gradually assembled into homogeneous hydrogel networks via the hydrophobic interaction and hydrogen bonding. Above 30 mM FA, high amount of FA promotes the formation of more rigid and densely packed networks in NaDC-FA hydrogels, where excessive FA-FA interactions disrupt the structural homogeneity of the hydrogels. The different microstructures of NaDC-FA hydrogels contribute to the appearance, melting temperature, and viscoelastic properties of the hydrogels as well as the transdermal permeation behavior of FA. The porcine skin permeation measurement suggests that the cumulative permeation amount of FA in NaDC-FA hydrogels with 50 mM FA is 7.1-fold relative to a saturated FA solution, indicating that the co-permeation of NaDC can reduce the free energy barrier for the transdermal permeation of FA. Moreover, bioactive FA loaded in NaDC-FA hydrogels achieves superior long-lasting free radical scavenging activity owing to the confined microenvironment of fibrous hydrogel networks.
The development of efficient, stable, and non-precious bifunctional electrocatalysts for overall water splitting is crucial for sustainable hydrogen production. Herein, we report the synthesis of a metal organic framework (MOF)-derived trimetallic CoFeCu catalyst anchored on a nickel-coated carbon nanotube scaffold (CoFeCu@Ni-CNT) via a facile solvothermal method. The outcome of an integrated electrocatalyst of CoFeCu@Ni-CNT exhibits exceptional activity for both the hydrogen and oxygen evolution reactions (HER and OER) in alkaline media. For the OER, it achieves a low overpotential of 220 mV at 10 mA cm-2, surpassing the performance of commercial RuO₂ (230 mV). For the HER, it requires an overpotential of only 49 mV, demonstrating performance approaching that of noble-metal benchmarks. Tafel analysis and electrochemical impedance spectroscopy confirm superior reaction kinetics and rapid charge transfer, attributed to the synergistic electronic modulation between Co, Fe, and Cu and the highly conductive Ni-CNT matrix. When employed in a two-electrode alkaline electrolyzer, the CoFeCu@Ni-CNT||CoFeCu@Ni-CNT configuration delivers a current density of 10 mA cm-2 at a low cell voltage of 1.51 V. Furthermore, the catalyst demonstrates outstanding long-term stability, maintaining its activity for over 24 h of continuous operation without degradation. This work provides a promising strategy for designing high-performance, durable electrocatalysts by engineering multi-metallic synergies on conductive hierarchical supports.
Permeation of viscous fluid in porous media has been attracted strenuous attention to comprehensively understand liquid-gas and liquid-liquid exchanges in a range of industrial fields as well as in nature. Precise prediction of immiscible-fluid displacement has not been made, however, even under viscous- and capillary- dominant or low Reynolds (Re) and capillary (Ca) number conditions, nevertheless localized interfacial events near the advancing flow fronts must be governing events within porous media with geometric anisotropy. Displacement of immiscible gas induced by viscous liquid is targeted by considering a geometry of a single-layer woven-fibrous porous medium in good wetting condition confined between flat and smooth parallel plates. Via experiments, fine controlled pressure reduction within the geometry induces viscous liquid permeation under designated pressure differences. Numerical simulation, validated by the present experiments, are also conducted by applying 'volume of fluid' and 'continuum surface force' methods to measure the velocity and pressure fields in well-reproduced permeation and resultant displacement of immiscible fluid. Twofold successive snap-off events in elongated immiscible fluid 'throat' trigger the formation of an isolated bubble, or void, entrapped in the inter-bundle region. Slight increment in Re and Ca, even though under Re ≪ 1 and Ca ≪ 1, results in only a single or no snap-off event due to the effect by the Young-Laplace pressure, leading to perfect displacement of the immiscible fluid sucked by their bulk downstream. Such sensitive reaction against Re and Ca is demonstrated to induce a drastic variation of macroscopic void fraction in the target geometry.
The persistent residues of tetracycline antibiotics in the environment poses serious ecological risks and health threats. This study proposes an active remediation strategy that integrates band-gap engineering and micro/nanoscale dynamics. Highly efficient photocatalytic micromotors were constructed by precisely engineering the heterojunction type in metal oxide semiconductors and systematically investigating their performance and mechanism for tetracycline degradation. Two micromotors were fabricated with completely different morphologies based on CuO-Co3O4 type-II and CdO-Co3O4 S-scheme heterojunctions using a facile template-free wet chemical method, followed by a hydrothermal process. Microstructural characterization confirmed the construction of the heterojunctions, where CdO-Co3O4 and the S-scheme heterojunction exhibited optimal photoinduced charge separation efficiency. Under the cooperative drive of visible light and low-concentration hydrogen peroxide, this S-scheme heterojunction micromotor demonstrated self-propulsion (speed >420 μm/s) and up to 99.1% degradation of tetracycline within 60 min. The degradation rate constant was 1.5 times and 311.2 times higher than that of the type-II heterojunction micromotor and their static counterpart, respectively. The S-scheme heterojunction effectively preserved the strong redox capabilities of its components and primarily generated reactive oxygen species, such as superoxide radicals. More importantly, the autonomous motion of the micromotor significantly enhanced fluid mixing and interfacial mass transfer, which led to a pronounced motion-enhanced catalysis effect. Additionally, the heterostructured micromotor was stable during five repetitions of tetracycline photodegradation. Our work offers a feasible strategy to integrate self-propelled micromotors with heterojunction photocatalysis and establishes a new design paradigm for the rapid degradation of pollutants in complex environmental systems.
The environmental mobility of As and Sb, which are hazardous to ecosystems and human health, depends on their oxidation state and interactions with mineral surfaces. Although boehmite (γ-AlOOH) is commonly used to adsorb oxyanionic contaminants, the relationships among its synthesis conditions, surface structure, and oxidation-state-dependent As and Sb adsorption mechanisms remain poorly understood. We hypothesized that hydrothermal synthesis conditions can be tuned to produce hierarchical mesoporous boehmite with optimized surface properties and that metalloid oxidation state governs adsorption mechanisms on this well-defined mineral surface. We optimized a one-pot hydrothermal method for synthesizing boehmite by systematically varying the pH, temperature, aging time, and aluminum concentrations, forming a plate-stacked spherical morphology with a high surface area and large pore volume. Adsorption isotherms revealed maximum As(III), As(V), and Sb(V) sorption capacities at pH 5/9 of 59.5/66.4, 38.1/13.5, and 54.6/16.0 mg/g, respectively. In contrast, the Sb(III) uptake (13 mg/g) was lowest at pH 5 but increased markedly at pH 9 because valentinite (Sb2O3) precipitated. Synchrotron-based spectroscopic analyses demonstrated that As(III/V) and Sb(V) form inner-sphere complexes with surface hydroxyl groups, whereas Sb(III) interacts mainly through weaker outer-sphere associations with negligible Al coordination. Molecular-scale structural interpretation further revealed that As(III) and As(V) form bidentate binuclear corner-sharing complexes on the boehmite surface, whereas Sb(V) forms both bidentate edge- and corner-sharing geometries. Therefore, metalloid adsorption was governed by oxidation-state-dependent surface complexation mechanisms, highlighting that efficiently removing As and Sb requires solution conditions tailored to each species. This study provides mechanistic insights into redox-dependent metalloid adsorption and demonstrates hydrothermally engineered boehmite as a high-capacity adsorbent among pristine aluminum oxyhydroxides without post-modification for metalloid remediation in complex aqueous systems.
Featuring both piezoelectric and photocatalytic properties, 2D Bi4Ti3O12 (BIT) offers high potential for uranium(VI) (U(VI)) remediation by efficiently suppressing photogenerated electron-hole recombination. However, its practical efficiency is severely limited by the low piezoelectric coefficient, insufficient active sites, and large bandgap. Herein, a series of alkaline-earth metals (ca, Sr, Ba, etc.) were, for the first time, introduced as A-site dopants in BIT to systematically investigate their piezo-photoelectric performance. Through combined theoretical and experimental verification, Ba-doping proved to be optimal for enhancing the piezo-photocatalysis of BIT. Accordingly, Ba-doped Bi4Ti3O12 (BBIT-x) catalysts with varying doping concentrations (x = 0.3, 0.5, 1.0, 2.0, 3.0) were synthesized for piezo-photocatalytic U(VI) removal. U(VI) capture experiments show that BBIT-0.5 possesses a superior U(VI) removal of 93.2% within 120 min under piezo-photocatalysis, far exceeding the 55.8% achieved by pristine BIT. Its kinetic rate constant is 3.5 times that of BIT, and 84.6 and 5.6 times those of the individual piezo-catalytic and photocatalytic modes, respectively. Mechanistic studies reveal that the superior U(VI) removal performance originates from the Ba-doping-induced synergistic effect, which promotes the generation of abundant electron-hole pairs via a narrowed bandgap, accelerates charge carrier separation through an enhanced built-in electric field, strengthens U(VI) capture by enriched oxygen vacancy sites, and enables the release of active sites upon the formation of uranyl deposits (i.e., UO2, (UO2)O2·4H2O) with electrons as the catalytic shuttle. Overall, this work deepens our understanding of the rational design of piezo-photocatalysts and offers mechanistic insight into nuclide pollution remediation.
Titanium dioxide (TiO2)-based conductive coatings are promising for aerospace, marine, and energy applications because of their environmental friendliness and low cost. However, yet their practical use is hindered by high photogenerated charge recombination and poor visible-light response. Although constructing triphasic heterostructures can enhance performance, their high-temperature instability remains a critical barrier. Herein, a synergistic strategy combining Co/Ni co-doping and graphene compositing is used: lattice stress caused by ionic radius differences generates a pinning effect that stabilize the anatase/brookite/rutile triphasic heterostructure, while chemical bonding with graphene constructs multilevel conductive pathways (Ti-O-C, Co-O-C, Ni-O-C). The built-in electric field at the triphasic heterointerfaces drives directional charge separation, and the highly conductive graphene network enables efficient carrier migration from the lattice to the interface, synergistically enhancing conductivity and establishing a dual charge transport mechanism. Structural characterization and theoretical calculations confirm that this strategy effectively stabilizes the multiphase structure and constructs multilevel conductive pathways. The resulting CN-T/G coating exhibits a low resistivity of 0.23 Ω · cm (a 79.6% reduction), a protection efficiency of 91.25%, super-hydrophobicity (water contact angle of 159.25°), and photocatalytic self-cleaning ability. This work provides a feasible design strategy for creating efficient, stable, and multifunctional TiO2-based conductive materials.
The development of efficient electrocatalysts capable of stable operation at ampere-level current densities is essential for industrial water electrolysis. Herein, based on the triple synergistic strategy of "hydrogen spillover-interfacial microenvironment regulation-wettability management", platinum‑tin (PtSn) nano-alloy modified with dahlia-like cobalt hydroxide fluoride (Co(OH)F) grown on nickel foam (NF), denoted as PtSn/Co(OH)F/NF, was fabricated via hydrothermal and electrochemical deposition techniques. Toward hydrogen evolution reaction (HER), the hydrogen spillover effect is driven by a Gibbs free energy of hydrogen adsorption (ΔGH) gradient between PtSn alloy and Co(OH)F carrier, leading to a significant increase in the active surface area at low platinum loadings. Additionally, tin (Sn) alloying accelerates water splitting kinetics by modulating the d-band center of platinum (Pt). For the oxygen evolution reaction (OER), the nanoneedle-induced tip effect enhances local electric fields, promoting hydroxide ion (OH-) enrichment and transport within the electrical double layer. Furthermore, the hierarchical "nanoneedle-nanoribbon-microflower" structure creates superhydrophilic and gas-repellent surface, facilitating rapid bubble release and mass transfer under high current densities. Thus, PtSn/Co(OH)F/NF delivered an overpotential of 15 ± 2 mV at 10 mA cm-2, and merely 212 ± 1 mV and 378 ± 2 mV to achieve 1 A cm-2 for HER and OER, respectively. Notably, cell voltages of only 1.47 and 1.68 V are required to achieve 10 and 500 mA cm-2, with an operational stability of 240 h. The hydrogen spillover mechanism was confirmed via density functional theory (DFT) calculation. This rational design strategy yields low-Pt electrocatalysts with optimized morphology and high intrinsic activity, offering a promising route for green energy applications.
Accurate identification of antioxidants is crucial for health assessment and food safety, yet conventional analytical methods often suffer from limited portability and operational efficiency. Herein, we propose an integrated microfluidic colorimetric sensor array based on a mixed-valence cerium metal-organic framework (MVCM) for the sensitive and patterned identification of six key antioxidant biomarkers. The MVCM exhibits exceptional oxidase-like activity, with density functional theory (DFT) calculations revealing that its catalytic prowess stems from a narrow bandgap (0.63 eV) and optimized adsorption energy for H2O2 and O2. The obtained MVCM can oxidate the 3,3',5,5'-tetramethylbenzidine (TMB) into oxTMB with blue color. By exploiting the differential inhibitory effects of biothiols and phenolic molecules on the MVCM-TMB system, a high-dimensional Red-Green-Blue (RGB) colorimetric fingerprint database was established. Integrated with machine learning-assisted principal component analysis (PCA), the sensor array achieved 100% classification accuracy for the six antioxidants within a linear range of 4-32 μM and maintained robust discrimination performance in complex binary and ternary mixture systems. This platform was further translated into a portable polydimethylsiloxane (PDMS)-glass microfluidic chip combined with smartphone imaging, enabling reliable assessment of antioxidant profiles in real samples. Overall, this work provides a low-cost, instrument-free, and non-invasive paradigm for point-of-care testing (POCT) and personalized oxidative stress monitoring.
The electrocatalytic carbon dioxide reduction reaction (CO2RR) is a highly promising strategy toward carbon neutrality. However, for its practical implementation, it is imperative to develop novel electrocatalysts that are structurally simple, cost-effective, and capable of delivering high current densities. Metal-organic frameworks (MOFs) are promising platforms due to their structural diversity and tunable functionality, but their practical catalytic performance is often hampered by low electrochemical activity and an insufficient number of intrinsic active sites. To address these challenges, this study employed a post-synthetic strategy by controlling the exposure of specific crystal facets to create a high concentration of molybdenum vacancies in hybrid zeolitic imidazolate frameworks (HZIF-Mo). The resulting defective MOF catalyst exhibits exceptional activity and selectivity in the CO2RR, achieving a maximum CO Faradaic efficiency of 86.5% in a flow cell and maintaining above 80% even at high current densities up to 500 mA cm-2. In situ infrared spectroscopy and Density Functional Theory (DFT) calculations revealed that the introduced Mo vacancies downshift the d-band center of metal nodes, weaken the adsorption of *CO and enhance the stabilization of the *COOH intermediate, thereby significantly improving CO selectivity. This work thus establishes a viable synthetic paradigm for high-performance defective MOF electrocatalysts and provides fundamental atomic-level insight into the vacancy-enhanced CO2RR mechanism.
TpPa-COF has arisen much attention as a semiconductor for photocatalytic hydrogen evolution reaction (HER), but the inefficient separation of photoelectrons and holes restricts its wide application. The metal-doped MoS2 nanoparticles are excellent conductive materials, which can accelerate the transfer of photoelectrons. In this case, a series of photocatalysts were constructed by in-situ growth of MMo6-S (M = Cu or Ni) nanoparticles on Tp-COF using Anderson-type polyoxometallates (POMs) as the metal source through a simple reflux method. The photocatalytic hydrogen evolution rate of CuMo6-S-TP-20 and NiMo6-S-TP-20 reached 13.33 and 7.24 mmol g-1 h-1 respectively without Pt as co-catalyst, resulting in 14.5-fold and 7.9-fold enhancements than pure TpPa-COF (0.92 mmol g-1 h-1). The ultra-small CuMo6-S nanoparticles with a diameter of 4.9 ± 0.4 nm are uniformly distributed on TpPa-COF, which can expose more active sites for photocatalytic HER. XPS and UPS analysis results reveal that there is a metallic 1T-MoS2 in ultra-small CuMo6-S nanoparticles. These metallic 1T-MoS2 can be able to form a Schottky heterojunction with TpPa-COF. Meanwhile, CuMo6-S-TP-20 has the most obvious photothermal effect, which can promote the rapid transfer of photogenerated electrons to improve the reaction activity. This research provides a new platform to explore novel co-catalysts for Tp-COFs to enhance the performance of photocatalytic HER.
Solar-driven valorization of renewable biomass derivatives under anaerobic conditions offers a sustainable route for the co-production of valuable chemicals and clean energy, yet the efficiency remains insufficient. Here, we report the rational design of a noble-metal-free NiSe2/ZnIn2S4 (NiSe2/ZIS) heterojunction photocatalyst for efficient anaerobic dehydrogenation of benzyl alcohol (BA) to benzaldehyde (BAD) coupled with stoichiometric H2 evolution under visible light. Benefitting from the layered structure, NiSe2 nanoparticles are well dispersed onto ultrathin ZIS nanosheets, forming a Schottky junction with strong interfacial electronic coupling. The large work function and metal-like conductivity of NiSe2 enable efficient extraction of photogenerated electrons from ZIS, while Se sites effectively promote H2 formation. As a result, the optimized NiSe2/ZIS photocatalyst delivers a high BAD production rate of 8363.2 μmol g-1 h-1 with simultaneous stoichiometric H2 evolution, approximately 4 times that of pristine ZIS, along with excellent selectivity and stability. This work demonstrates an effective strategy for coupling biomass-derived alcohol upgrading with clean hydrogen production and provides valuable insights into the design of efficient Schottky junction photocatalysts for sustainable solar-driven organic transformations.
Cobalt disulfide (CoS2), noted for its high theoretical specific capacity, is considered a promising anode material for sodium-ion batteries. However, the cycling and rate capabilities are limited by sluggish charge transfer kinetics and poor structural stability. To address these challenges, heterojunction engineering has been identified as a viable solution. In this study, hollow nanocubic crystalline-amorphous CoS2/NC@MoS2 heterostructures have been fabricated using template-guided strategy and stepwise sulfidation approach. This design effectively establishes an interfacial built-in electric field activated by crystalline CoS2 and amorphous MoS2. Furthermore, the unique hollow heterostructure combines the benefits of highly conductive crystalline frameworks and amorphous phases rich in active sites, thereby synergistically enhancing electrochemical kinetics and structural integrity. As anticipated, the CoS2/NC@MoS2 anode achieves a reversible capacity of 427 mAh g-1 at 0.5 A g-1, demonstrates superior rate performance with 299.5 mAh g-1 at 10 A g-1, and exhibits exceptional cycling stability, retaining 301.9 mAh g-1 after 2000 cycles at 2 A g-1. This work establishes an effective paradigm for designing high-performance heterostructured anodes through precise control of crystallinity and interface engineering, offering new insights into the development of advanced SIBs materials.
Cellulose-based hydrogels hold great promise as electrolytes for aqueous Zinc-ion batteries (ZIBs), yet their performance is hindered by chain aggregation, overly strong Zn2+-cellulose coordination that slows ion transport, and parasitic reactions triggered by free water and sulfate species. Here, we design a multifunctional cellulose nanofiber (CNF) hydrogel electrolyte incorporating copper hybrid cluster Cu4I4(L)4 (L = 3-Fluoropyridine (3-FPy)) to address these intrinsic limitations. Strong interactions between the clusters and cellulose chains prevent molecular aggregation and introduce additional crosslinking, reorganizing the network into a more continuous and uniform 3D architecture. Unexpectedly, the hydrogel develops a sandwiched structure consisting of dense outer layers that homogenize Zn2+ flux and shield the anode from free water, and a porous intermediate layer that serves as an electrolyte reservoir to facilitate long-range ion migration. The clusters exhibit weaker affinity toward Zn2+ than cellulose, mitigating excessive Zn2+-polymer coordination and enabling faster ion movement. Their spatially polarized charge distribution also provides sequential Zn2+ hopping sites, further promoting directional ion transport. Meanwhile, strong binding with H2O and SO42- converts free water into bound water and immobilizes anions, thereby suppressing H2O- and SO42--driven parasitic reactions. Benefiting from this cooperative regulation of microstructure, ion coordination, and water chemistry, the CNF@Cu4I4(L)4 hydrogel exhibits high ionic conductivity, stable Zn plating/stripping, and effectively suppressed side reactions. As a result, Zn anodes achieve a long-term cycling stability up to 1200 h, and capacity retention of 99.5% over 2000 cycles for Zn||Polyaniline full cells. This work establishes a robust strategy for engineering cluster-modified hydrogels toward safe, durable, and high-performance aqueous ZIBs.