Transpiration-Inspired Fabric Dressing for Acceleration Healing of Wound Infected with Biofilm

In chronic wound management, efficacious handling of exudate and bacterial infections stands as a paramount challenge. Here a novel biomimetic fabric, inspired by the natural transpiration mechanisms in plants, is introduced. Uniquely, the fabric combines a commercial polyethylene terephthalate (PET) fabric with asymmetrically grown 1D rutile titanium dioxide (TiO2) micro/nanostructures, emulating critical plant features: hierarchically porous networks and hydrophilic water conduction channels. This structure endows the fabric with exceptional antigravity wicking-evaporation performance, evidenced by a 780% one-way transport capability and a 0.75 g h-1 water evaporation rate, which significantly surpasses that of conventional moisture-wicking textiles. Moreover, the incorporated 1D rutile TiO2 micro/nanostructures present solar-light induced antibacterial activity, crucial for disrupting and eradicating wound biofilms. The biomimetic transpiration fabric is employed to drain exudate and eradicate biofilms in Staphylococcus aureus (S. aureus)-infected wounds, demonstrating a much faster infection eradication capability compared to clinically common ciprofloxacin irrigation. These findings illuminate the path for developing high-performance, textile-based wound dressings, offering efficient clinical platforms to combat biofilms associated with chronic wounds.

Urease-Powered Black TiO2 Micromotors for Photothermal Therapy of Bladder Cancer

Urease-powered nano/micromotors can move at physiological urea concentrations, making them useful for biomedical applications, such as treating bladder cancer. However, their movement in biological environments is still challenging. Herein, Janus micromotors based on black TiO2 with urease asymmetric catalytic coating were designed to take benefit of the optical properties of black TiO2 under near-infrared light and the movement capability in simulated bladder environments (urea). The black TiO2 microspheres were half-coated with a thin layer of Au, and l-Cysteine was utilized to attach the urease enzyme to the Au surface using its thiol group. Biocatalytic hydrolysis of urea through urease at biologically relevant concentrations provided the driving force for micromotors. A variety of parameters, such as urea fuel concentration, viscosity, and ionic character of the environment, were used to investigate how micromotors moved in different concentrations of urea in water, PBS, NaCl, and urine. The results indicate that micromotors are propelled through ionic self-diffusiophoresis caused by urea enzymatic catalysis. Due to their low toxicity and in vitro anticancer effect, micromotors are effective agents for photothermal therapy, which can help kill bladder cancer cells. These promising results suggest that biocompatible micromotors hold great potential for improving cancer treatment and facilitating diagnosis.

Constructing 3D hierarchical TiO2 microspheres with enhanced mass diffusion for efficient glucose photoreforming under modulated reaction conditions

Three-dimensional (3D) TiO2 hierarchical microspheres (THMs) were successfully prepared via a facial template-free hydrothermal approach. The possible growth mechanism of THM was also investigated by TiCl4 concentration-, time-, and temperature-dependent experiments. The results indicate that the formation of an urchin-like hierarchical structure may follow a "nucleation-dissolution and recrystallization-assembly" process. THM was employed for photoreforming under various catalyst and glucose concentrations, solvent compositions, and pH values. The H2 production rate, glucose conversion, arabinose and formic acid selectivity reached 9.44 mmol gcat.-1h-1, 86.35%, 11.32%, and 46.87%, respectively, under the modulated condition with Pt as cocatalyst; this is attributed to the enhanced mass diffusion caused by the 3D hierarchical morphology as well as the interaction between unsaturated Ti atoms (or oxygen vacancies) in THM and the hydroxyl oxygen atoms on glucose. In addition, the enhanced light absorption induced by defects also exerts a positive effect. In this work, we present an emerging sustainable strategy for the coproduction of H2 and value-added chemicals from biomass-based glucose with economic photocatalysts under mild conditions.

Progress in Preparation of Sea Urchin-like Micro-/Nanoparticles

Urchin-like microparticles/nanoparticles assembled from radial nanorods have a good appearance and high specific surface area, providing more exposed active sites and shortening the diffusion path of photoexcited carriers from the interior to the surface. The interfacial interaction and physical and chemical properties of the materials can be improved by the interfacial porous network induced by interlacing nano-branches. In addition, multiple reflections of the layered microstructure can absorb more incident light and improve the photocatalytic performance. Therefore, the synthesis and functionalization of three-dimensional urchin-like nanostructures with controllable size, shape, and hierarchy have attracted extensive attention. This review aims to provide an overview to summarize the structures, mechanism, and application of urchin-like microparticles/nanoparticles derived from diverse synthesis methods and decoration types. Firstly, the synthesis methods of solid urchin-like micro-/nanoparticles are listed, with emphasis on the hydrothermal/solvothermal method and the reaction mechanism of several typical examples. Subsequently, the preparation method of composite urchin-like micro-/nanoparticles is described from the perspective of coating and doping. Then, the research progress of urchin-like hollow microspheres is reviewed from the perspective of the step-by-step method and synchronous method, and the formation mechanism of forming urchin-like hollow microspheres is discussed. Finally, the application progress of sea urchin-like particles in the fields of photocatalysis, electrochemistry, electromagnetic wave absorption, electrorheological, and gas sensors is summarized.

Radial TiO2 Nanorod-Based Mesocrystals: Synthesis, Characterization, and Applications

Radial TiO2 nanorod-based mesocrystals (TiO2-NR MCs) or so-called “sea-urchin-like microspheres” possess not only attractive appearance but also excellent potential as photocatalyst and electrode materials. As a new type of TiO2-NR MCs, we have recently developed a radial heteromesocrystal photocatalyst consisting of SnO2(head) and rutile TiO2 nanorods(tail) (TiO2-NR//SnO2 HEMCs, symbol “//” denotes heteroepitaxial junction) with the SnO2 head oriented in the central direction in a series of the studies on the nanohybrid photocatalysts with atomically commensurate junctions. This review article reports the fundamentals of TiO2-NR MCs and the applications to photocatalysts and electrodes. Firstly, the synthesis and characterization of TiO2-NR//SnO2 HEMCs is described. Secondly, the photocatalytic activity of recent TiO2-NR MCs and the photocatalytic action mechanism are discussed. Thirdly, the applications of TiO2-NR MCs and the analogs to the electrodes of solar cells and lithium-ion batteries are considered. Finally, we summarize the conclusions with the possible future subjects.

Multifunctional Textiles Based on Three-Dimensional Hierarchically Structured TiO2 Nanowires

The development of three-dimensional (3D) micro-/nanostructures with multiscale hierarchy offers new potential for the improvement of the pristine textile properties. In this work, a polyester fabric coated with 3D hierarchically structured rutile TiO₂ nanowires (THNWP) was fabricated by a facile hydrothermal strategy. The THNWP samples exhibit markedly improved photocatalytic activities and antibacterial properties owing to their 3D hierarchical architecture constructed by one-dimensional nanowire structures, good crystallinity, excellent light-harvesting capability, and fast electron-transfer rate. Furthermore, the unique 3D hierarchical nanostructures also combine with the monofilament to produce ternary-scale hierarchy, which endows the fabric surface with outstanding superamphiphobicity after further facile fluorination treatment. The supportive air-pockets trapped within the unique ternary-scale architectures are proved to be the crucial factor in the achievement of high liquid repellency, and the highest performing superamphiphobic surface is capable of repelling liquids down to a minimal surface tension of 23.4 mN m^-1. We envision that our findings may possess great potential in the bottom-up design of high-performance textiles.

Synthesis of 1D-Anisotropic Particles Consisting of TiO2 Nanorods and SnO2 with Heteroepitaxial Junctions and Self-Assembled 3D-Microspheres

Anisotropic one-dimensional (1D)-particles with a SnO₂ "head", a TiO₂ "tail", and self-assembled three-dimensional (3D)-microspheres were synthesized by a hydrothermal method. At the first stage of the reaction, an amorphous TiO₂ layer is deposited on the SnO₂ surface. At the second stage, rutile nuclei are generated in the amorphous TiO₂ layer. At the third stage, a single TiO₂ nanorod grows from a SnO₂ particle with a heteroepitaxial relation of TiO₂(001)//SnO₂(001). Finally, the resulting 1D-anisotropic hybrid particles are self-assembled to form a radial 3D-microsphere with the SnO₂ head oriented in the central direction.

Lanthanide-doped KYb3F10 crystals: controllable phases, rich morphologies and Tb3+/Eu3+ down-conversion emission

KYb₃F₁₀:Ln³⁺ (Ln = Er, Ho, Tb, Gd, Eu, Sm, Ce and La) micro/nanocrystals with abundant morphologies were synthesized via a one-step hydrothermal route without employing any surfactants.

Enhanced degradation of ciprofloxacin by graphitized mesoporous carbon (GMC)-TiO2 nanocomposite: Strong synergy of adsorption-photocatalysis and antibiotics degradation mechanism

In order to achieve remarkable synergy between adsorption and photocatalysis for antibiotics elimination from water, in this study, a graphitized mesoporous carbon (GMC)-TiO₂ nanocomposite was successfully synthesized by an extended resorcinol-formaldehyde (R-F) method. In the composite, the lamellar GMC nanosheets possessed large specific surface area and mesoporous structure, and could adsorb and enrich antibiotics effectively. This could not only reduce the antibiotic concentration in water shortly, but also greatly increase the chances for antibiotics to contact with and be degraded by photocatalysts and active species. Interestingly, GMC could also facilitate the transportation of photogenerated electrons to further improve the photocatalytic efficiency of TiO₂, and 15 mg/L ciprofloxacin (CIP) could be totally mineralized in 1.5 h. Meanwhile, the biological inhibition of reaction solution on luminescence bacteria decreased obviously with antibiotics degradation until non-toxicity, reinforcing the thorough elimination of antibiotics. Besides, from the viewpoint of organic chemistry, several plausible CIP degradation pathways were established using HPLC-MS technique, and an interesting intermediate with five-membered ring structure was firstly proposed, which is helpful to deeply understand CIP degradation. Strong synergy between adsorption and photocatalysis, along with quick and efficient antibiotics elimination, double confirm the great potential of GMC-TiO₂ nanocomposite for practical antibiotic wastewater purification.

Morphology/phase controllable synthesis of monodisperse ScVO4 microcrystals and tunable multicolor luminescence properties in Sc(La)VO4(PO4):Bi3+,Ln3+ phosphors

A facile one-pot hydrothermal approach was employed to prepare novel chocolate-like ScVO₄ microcrystals using polyethylene glycol as an additive.