Search Results (209)

We report a galvanic replacement-driven strategy for the in situ growth of highly uniform one-dimensional (1D) Cu@CuO-X (X = Ag, Bi) nanobelts directly on aluminum foils. Unlike conventional multi-step coating or hard-template replication strategies, the formation of these heterostructured nanobelts is governed by a spontaneous interfacial galvanic replacement process between Cu and the introduced metal species, ensuring in situ growth and intimate interfacial integration. Comprehensive SEM, TEM, XRD, and XPS characterizations confirm the successful formation of Cu@CuO-Ag and Cu@CuO-Bi architectures, where Bi predominantly exists in the oxidized Bi³⁺ state, forming Bi₂O₃-like surface species. Benefiting from their 1D anisotropic framework and controllable heterointerfaces, this work underscores the distinctiveness and versatility of the self-templated galvanic replacement strategy for the design of multifunctional nanomaterials. Full article

Porous Ti-6Al-4V foams are excellent materials due to their low density, high specific strength, and excellent biocompatibility. This study investigates the fabrication of open-cell Ti-6Al-4V foams using the replica impregnation method with polyurethane templates of varying pore sizes (20, 25, and 30 ppi) and sintering temperatures (1170 °C, 1200 °C, 1250 °C, and 1280 °C). The effects of these parameters on microstructural evolution, phase composition, and mechanical properties were examined. Microstructural analysis showed that optimum densification occurred at 1250 °C. However, at 1280 °C, excessive grain growth and pore coarsening were observed. XRD, SEM, and EDS analyses confirmed that α-Ti was the matrix phase, while titanium carbide formed in situ as a result of the carbon residues released from the decomposed polyurethane template. With the development of the TiC phase and enhanced interparticle bonding due to sintering, the compressive strength progressively increased up to 1250 °C. At 1280 °C, strength decreased due to excessive TiC growth, causing brittleness and pore coarsening, reducing structural integrity. Maximum compressive strength of 40.2 MPa and elastic modulus of 858.9 MPa were achieved at 1250 °C with balanced TiC dispersion and pore structure. Max density of 1.234 g/cm³ was obtained at 1250 °C. Gibson-Ashby analysis and the fracture surfaces confirmed the brittle behavior of the foams, which is attributed to the presence of TiC particles and microcracks in the structure. The study concludes that 1250 °C provides an ideal balance between densification and structural integrity, offering valuable insights for biomedical and structural applications. Full article

The development of oil–water separation materials that combine high separation efficiency, robust mechanical properties, and environmental degradability remains a significant challenge. This study presents a novel degradable and superhydrophobic porous material fabricated via a multi-step process. A porous foam was first synthesized from degradable poly(ε-caprolactone-co-2-ethylhexyl acrylate) using a high internal phase emulsion templating technique. The foam was subsequently modified through in situ silica (SiO₂) deposition via a sol–gel process, followed by grafting with hydrophobic hexadecyltrimethoxysilane (HDTMS) to produce the final oil–water separation porous materials. Various characterization results showed that the optimized material featured a hierarchical pore structure in micro scales and the porosity of the foam remained ~90% even after the 2-step modification. Mechanical tests indicate that the modified material exhibited significantly enhanced compressive strength and the water contact angle measurements revealed a superhydrophobic surface with a value of approximately 156°. The prepared material demonstrated excellent oil/water separation performance with notable absorption capacities ranging from 4.11 to 4.90 g/g for oils with different viscosity. Additionally, the porous material exhibited exceptional cyclic stability, maintaining over 90% absorption capacity after 10 absorption-desorption cycles. Moreover, the prepared material achieved a mass loss of approximately 30% within the first 3 days under alkaline hydrolysis conditions (pH 12, 25 °C), which further escalated to ~70% degradation within four weeks. The current work establishes a feasible strategy for developing sustainable, high-performance oil–water separation materials through rational structural design and surface engineering. Full article

In this study, a rough-surfaced LiFePO₄ (RS-LFP) cathode material with a well-defined porous architecture was successfully synthesized via a scalable, template-assisted spray drying method. The resulting RS-LFP exhibited a high specific surface area of 41.2 m² g⁻¹, significantly enhancing electrode–electrolyte contact. This tailored microstructure, combined with an in-situ-formed carbon network, reduced the charge-transfer resistance and facilitated efficient ion/electron transport. Consequently, the RS-LFP demonstrated outstanding electrochemical performance, including a high initial capacity of ~140 mAh g⁻¹ at 0.2 C, excellent cycling stability with over 95% capacity retention after 30 cycles, and superior rate capability. The RS-LFP also exhibited a remarkable capacity recovery of ~99% when the current returned to 0.2 C. These findings highlight that engineering porous architectures through template-assisted spray drying is a promising and scalable strategy for developing high-performance phosphate-based cathodes for advanced energy storage applications. Full article

To address the challenges of low solar energy utilization efficiency and rapid recombination of photogenerated charge carriers in photocatalytic hydrogen evolution, this study successfully constructed a composite photocatalyst of ZnIn₂S₄ (ZIS) supported on N-doped hollow carbon spheres (N-HCS), denoted as ZIS/N-HCS, via a combination of template etching and in situ growth strategies. Characterization results demonstrate that this hollow structure possesses a high specific surface area (48.41 m²/g) and a narrowed bandgap (2.41 eV), achieve broad-spectrum light absorption, thereby enabling the catalyst to generate a local hot spot temperature of 136 °C under AM1.5G conditions. The optimized ZIS/N-HCS-0.30 sample exhibited a significantly enhanced photocurrent response (8.26 μA cm⁻²) and improved charge separation efficiency. When evaluated at a set solution temperature of 20 °C, the material exhibited a photocatalytic hydrogen evolution rate of 17.03 mmol g⁻¹·h⁻¹, which is 7.06 times higher than that of pure ZIS. Furthermore, it demonstrated excellent cycling stability. This work elucidates the synergistic role of the hollow photothermal structure in enhancing solar energy utilization and catalytic reaction kinetics, providing a new strategy for designing efficient solar-driven hydrogen production systems. Full article

Tin-based materials have emerged as promising anode candidates for advanced lithium-ion batteries (LIBs) due to their high theoretical capacity (e.g., 994 mAh·g⁻¹ for Li₄.₄Sn), moderate operating potential, and natural abundance. However, Tin-based materials suffer from severe volume expansion (>300%) and rapid capacity decay during cycling. To mitigate these challenges, a composite composed of tin-based materials and porous carbon (PC), i.e., SnO₂/SnS₂@PC, was prepared by calcining a mixture of SnO₂, petroleum asphalt and calcium carbonate at high temperature, where petroleum asphalt acted as the carbon and sulfur resource, and calcium carbonate acted as a pore-forming template. The prepared SnO₂/SnS₂@PC composite had a specific surface area of 190 m²·g⁻¹ with total pore volume 0.386 cm³·g⁻¹, and delivered an initial specific capacity of 1431 mAh·g⁻¹ and retained 722 mAh·g⁻¹ at 100th cycle at 0.2 A·g⁻¹, which is nearly three folds that of the actual capacity (~260 mAh·g⁻¹) of commercial graphite. The novelty of this work lies in that the abundant sulfur element in petroleum asphalt was fully utilized to react in situ with nano SnO₂ to generate SnS₂ and form a composite with high specific capacity and good structural stability, along with greatly reducing the emission of the harmful element sulfur into the atmosphere. Full article

In this study, patch-structured C₈/CHO template microspheres were successfully synthesized through in situ reduction and sol–gel reactions, providing a reusable platform for subsequent modifications. Based on these templates, temperature-responsive PW₁₂O₄₀³⁻-PILs/PNIPAM Janus nanosheets were prepared via sequential Schiff-base coupling and ATRP. Structural characterizations (XRD, SEM, TEM, FTIR, and TGA) confirmed successful functionalization and nanosheet formation. The PNIPAM moiety endowed the nanosheets with temperature responsiveness, while the incorporation of polymerized ionic liquids and phosphotungstate anions further enhanced amphiphilicity and dispersion stability. When applied as particulate emulsifiers in water/toluene systems, the Janus nanosheets formed stable Pickering emulsions at elevated temperatures and underwent reversible emulsification–demulsification upon temperature cycling. These findings demonstrate the potential of PW₁₂O₄₀³⁻-PILs/PNIPAM Janus nanosheets as smart emulsifiers for responsive separation and formulation technologies. Full article

This study introduces nitrogen- and silicon-containing carbon quantum dots (N,Si-CQDs), synthesized hydrothermally from the sustainable bioresource stinging nettle (Urtica dioica L.), as chemically active supports for Pt, Pd, and Pt₃Pd₁ electrocatalysts. The N,Si-CQDs were characterized by a high concentration of N/O surface functionalities and the presence of biogenic Si. A significant finding is that, with this support, biogenic Si acts as a nucleation template: Pd forms in situ as orthorhombic Pd₉Si₂ nanorods alongside spherical particles, whereas Pt predominantly develops as cubic/quasi-cubic crystals. This templating process promotes faceted (cubic) Pt₃Pd₁ alloy nanoparticles with robust interfacial contact with the support and a log-normal size distribution (14.2 ± 4.3 nm) on N,Si-CQDs (4.7 ± 1.4 nm). This configuration enhanced the electrochemically active surface area to 181 m² gPt⁻¹, significantly exceeding those of commercial Pt₁Pd₁/XC-72 (27.7 m² gPt⁻¹) and monometallic Pt/N,Si-CQDs (14.3 m² gPt⁻¹). Consequently, the catalyst demonstrated superior methanol oxidation performance, evidenced by a low onset potential (0.17 V), approximately 10-fold higher mass activity compared to Pt₁Pd₁/XC-72, and 53% activity retention after a 16 h accelerated durability test. The enhanced performance is attributed to the strong nanoparticle anchoring by N,Si-CQDs, the bifunctional/ligand effects of the Pt–Pd alloy that improve CO tolerance, and the templating role of biogenic Si. Full article

Surface-enhanced Raman spectroscopy (SERS) enables ultra-sensitive molecular detection and has broad analytical and biomedical applications; recent advances focus on high-performance substrates and innovative detection strategies. However, achieving controllable and reproducible substrate fabrication—particularly using natural templates such as hair—remains challenging, limiting SERS application in trace analysis and on-site detection. This study developed a single-hair in situ SERS platform using a natural hair template. Confinement within hair cuticle grooves and capillary-evaporation assembly enables dense arrangement of cetyltrimethylammonium bromide-coated Au nanorods and polyvinylpyrrolidone-coated Au nanoparticles, forming uniform plasmonic nanoarrays. Spectroscopy and microscopy analyses confirmed the regular alignment of nanostructures along the hair axis with denser packing at the edges. The platform detected crystal violet at 10⁻⁹ M, yielding clear signals, negligible background, and stable peaks after repeated washing. For p-phenylenediamine, enhancement was observed down to 10⁻⁶ M. On the platform, a concentration-dependent response appeared within 10⁻³–10⁻⁵ M, with spatial Raman imaging along the hair axis. Capillary-evaporation coupling and interfacial wettability facilitated solute enrichment from larger to smaller gap hotspots, improving signal-to-noise ratio and reproducibility. This portable, low-cost, and scalable method supports rapid on-site screening in complex matrixes, offering a general strategy for hotspot engineering and programmable assembly on natural templates. Full article

The development of single-crystal Ni-rich layered cathode materials (SC-NCMs) is regarded as an effective strategy to address the mechanical failure issues commonly associated with polycrystalline counterparts. However, the industrial production of SC-NCM faces challenges such as lengthy processing steps, high manufacturing costs, and inconsistent product quality. In this study, we innovatively propose a metal/organic framework (MOF)-mediated one-step synthesis strategy to achieve controllable structural preparation and in situ Nb⁵⁺ doping in SC-NCM. Using a Ni–Co–Mn-based MOF as both precursor and self-template, we precisely regulated the thermal treatment pathway to guide the nucleation and oriented growth of high-density SC-NCM particles. Simultaneously, Nb⁵⁺ was pre-anchored within the MOF framework, enabling atomic-level homogeneous doping into the transition metal layers during crystal growth. Exceptional electrochemical performance is revealed in the in situ Nb-doped SC-NCM, with an initial discharge capacity reaching 176 mAh/g at a 1C rate and a remarkable capacity retention of 86.36% maintained after 200 cycles. This study paves a versatile and innovative pathway for the design of high-stability, high-energy-density cathode materials via a MOF-mediated synthesis strategy, enabling precise manipulation of both morphology and chemical composition. Full article

Titanium dioxide (TiO₂), owing to its excellent photocatalytic performance and environmental friendliness, holds great potential in the remediation of water pollution. In this study, we introduce a green and facile strategy to fabricate TiO₂-based hybrid aerogels, in which the peptide FQFQFIFK first self-assembles into peptide nanofibers (PNFs), followed by in situ biomineralization of TiO₂ on the PNFs. The TiO₂-loaded PNFs are then combined with graphene oxide (GO) via π–π interactions and integrated with microcrystalline cellulose (MCC) to construct a stable three-dimensional (3D) porous framework. The resulting GO/MCC/PNFs-TiO₂ aerogels exhibit high porosity, low density, and good mechanical stability. Photocatalytic experiments show that the aerogels efficiently degrade various organic dyes (methylene blue, rhodamine B, crystal violet, and Orange II) and antibiotics (e.g., tetracycline) under visible-light irradiation, achieving final degradation efficiencies higher than 90%. The excellent performance is attributed to the synergistic effect of the ordered interface provided by the PNF template, the stabilization and uniform dispersion facilitated by GO, and the mechanically robust 3D scaffold constructed by MCC. This work provides an efficient and sustainable strategy for designing functional hybrid aerogels and lays a foundation for their application in water treatment and environmental remediation. Full article

Addressing the challenge of sulfonated lignite (SL) removal from oilfield wastewater, this study introduces a novel hierarchical MgFe-layered double hydroxide (LDH) adsorbent. The material was fabricated via in situ co-precipitation, utilizing a template formed by the NaCl-induced co-assembly of oleylaminopropyl betaine (OAPB) and sodium dodecyl sulfate (SLS) into zwitterionic, anionic, shear-responsive viscoelastic gels. This gel-templating approach yielded an LDH structure featuring a hierarchical pore network spanning 1–80 nm and a notably high specific surface area of 199.82 m²/g, as characterized by SEM and BET. The resulting MgFe-LDH demonstrated exceptional efficacy, achieving a SL removal efficiency exceeding 96% and a maximum adsorption capacity of 90.68 mg/g at neutral pH. Adsorption kinetics were best described by a pseudo-second-order model (R² > 0.99), with intra-particle diffusion identified as the rate-determining step. Equilibrium adsorption data conformed to the Langmuir isotherm, signifying monolayer uptake. Thermodynamic analysis confirmed the process was spontaneous (ΔG < 0) and exothermic (ΔH = −20.09 kJ/mol), driven primarily by electrostatic interactions and ion exchange. The adsorbent exhibited robust recyclability, maintaining over 79% of its initial capacity after three adsorption–desorption cycles. This gel-directed synthesis presents a sustainable pathway for developing high-performance adsorbents targeting complex contaminants in oilfield effluents. Full article

Ice nucleation temperatures and associated ice growth rates are critical parameters in defining the initial ice morphology template, which governs dry layer resistance during sublimation and therefore impacts primary drying kinetics and overall process time. In this study, we developed a through-vial impedance spectroscopy (TVIS) method to determine both ice nucleation temperature and average ice growth rate, from which future estimation of average ice crystal size may be possible. Whereas previous TVIS applications were limited to solutions containing simple, uncharged solutes such as sugars, our adapted approach enables the analysis of conductive solutions (5% sucrose with 0%, 0.26%, and 0.55% NaCl), covering osmolarities below and above isotonicity. We established that the real part capacitance at low and high frequencies—either side of the dielectric relaxation of ice—provides the following: (i) a temperature-sensitive parameter for detecting the onset of ice formation, and (ii) a temperature-insensitive parameter for determining the end of the ice growth phase (unaffected by temperature changes in the frozen solution). This expanded capability demonstrates the potential of TVIS as a process analytical technology (PAT) for non-invasive, in situ monitoring of freezing dynamics in pharmaceutical freeze-drying. Full article

Graphitic carbon nitride (g-C₃N₄)-based materials hold significant promise for environmental remediation, particularly water purification, owing to their unique electronic structure, metal-free composition, and robust chemical stability. However, powdered g-C₃N₄ faces challenges such as particle aggregation, poor recyclability, and limited exposure of active sites. Structuring g-C₃N₄ into hydrogels or aerogels—three-dimensional porous networks offering high surface area, rapid mass transport, and tunable porosity—represents a transformative solution. This review comprehensively examines recent advances in g-C₃N₄-based gels, covering synthesis strategies such as crosslinking (physical/chemical), in situ polymerization, and the sol–gel and template method. Modification approaches including chemical composition and structural engineering are systematically categorized to elucidate their roles in optimizing catalytic activity, stability, and multifunctionality. Special emphasis is placed on environmental applications, including the removal of emerging contaminants and heavy metal ions, as well as solar-driven interfacial evaporation for desalination. Throughout, the critical interplay between gel structure/composition and performance is evaluated to establish design principles for next-generation materials. Finally, this review identifies current challenges regarding scalable synthesis, long-term stability, in-depth mechanistic understanding, and performance in complex real wastewater matrices. This work aims to provide valuable insights and guidance for advancing g-C₃N₄-based hydrogel and aerogel technologies in environmental applications. Full article

Metal–organic frameworks (MOFs) have become a hot topic in various research fields nowadays. And MOF-derived metal oxides prepared by the sacrificial template method have been widely applied as catalysts for pollutant removal. Accordingly, we prepared a series of MOF-derived MnO_x catalysts with diverse morphologies (rod-like, flower-like, slab-like) via the pyrolysis of MOF precursors, and the as-prepared MnO_x catalysts demonstrated superior performance compared to the one prepared using the co-precipitation method. MnO_x-II, with a flower-like structure, exhibited excellent activity for formaldehyde (HCHO) catalytic ozonation at room temperature, reaching complete HCHO conversion at O₃/HCHO of 1.5 and more than 90% CO₂ selectivity at an O₃/HCHO ratio of 2.5. On the basis of various characterization methods, it was clarified that the enhanced catalytic performance of MnO_x-II benefited from its larger BET surface area, abundant oxygen vacancies, better redox ability at lower temperature, and more Lewis acid sites. The H₂O resistance and stability tests were also conducted. Furthermore, DFT calculations substantiated the enhanced adsorption of HCHO and O₃ on oxygen vacancies, while in–situ DRIFTS measurements elucidated the degradation pathway of HCHO during catalytic ozonation through detected intermediates. Full article