Large size bone defects typically need a long recovery period of more than three months, while a rapid repair of large bone defects is of great important and presents a significant challenge in clinical. Osteoinduction and osteoconduction provide different pathways and biofunctions for bone repair. Here, a biomimetic bone spatial architecture scaffold loaded with drug were constructed for satisfied both of these two bone repair biofunctions. Contacted with the host bone tissue, the HAp scaffold facilitates osteoconduction mainly through the outer layer of the scaffold. Meanwhile, GelMA loaded drugs primarily facilitates osteoinduction in the inner layer of the scaffold by establishing an osteogenic microenvironment. In vitro cell experiments confirmed that HAp/GelMA/IC showed excellent biocompatibility and osteogenic differentiation. An animal model of rabbit femoral condyle defect confirmed that HAp/GelMA/IC promoted osteoinduction and osteoconduction biofunctions. This dual biofunctions design provided a promising strategy for fast bone reconstruction in the large size bone defects repair. Graphical abstract Download : Download high-res image (307KB) Download : Download full-size image

The direct conversion of heat and electric energy through thermoelectric effects is one of the effective ways to improve energy efficiency and reduce carbon emission. Thermoelectric parameters are the basis to evaluate the thermoelectric conversion efficiency of thermoelectric materials. However, the measurement of thermoelectric properties in micro/nano thermoelectric materials is extremely difficult at a small scale. Accurate and rapid characterization of thermoelectric parameters is the foundation and key of the optimization design and application of thermoelectric materials. The small-scale and micro-nano structure of materials cannot only effectively change its thermal conductivity, but also affect its electrical conductivity and Seebeck coefficient, thus significantly improving the thermoelectric conversion efficiency. Therefore, it is urgent to study the coupling mechanism between micro-/nano- scale structure regulation and thermoelectric conversion. In this work, an in-situ characterization technique is proposed for the integration of structural regulation and thermoelectric properties of micro/nano materials, and the coupling mechanism is also investigated experimentally. The micro-nano structure of materials is controlled by micro-machining method to realize the adjustable and controllable conversion efficiency. The results demonstrated that structural regulation could effectively improve the ZT value with a maximum improvement of nearly 7 times, which indicated that it was an effective approach to improve the thermoelectric performance. Graphical abstract Download : Download high-res image (188KB) Download : Download full-size image

Dielectric ceramic capacitors play a crucial role in energy electricity and electronic circuit systems owing to their exceptional ability to rapidly store and release electrical charge and remarkable power density. However, they still face critical challenges related to improving recoverable energy storage density (Wrec) and efficiency (η) synergistically. To address these issues, a novel relaxor ceramic system is designed in this work by introducing linear dielectric SrTiO3 (ST) into ferroelectric Bi0.5K0.5TiO3-BiFeO3 (BKT-BF) with large polarization. XRD refinement and TEM characterization demonstrate the coexistence of Rhombohedral (R3mr), Tetragonal (P4mm) and Cubic (Pm-3m) phases, which induces polar nano-regions (PNRs) in the ceramic and gives rise a decreased remanent polarization (Pr) and an enhanced η. SEM and ultraviolet–visible spectrum confirm a decreased grain size and a widened bandgap, leading to an ultra-high breakdown electric field. Therefore, a superior recoverable Wrec of 7.32 J/cm3 and an impressive η of 88.06% are achieved, accompanied by prominent stability across a wide temperature range (30-150 ℃), various frequencies (1-500 Hz), and a substantial number of cycles (1-105 cycles) in the BKT-BF-0.4ST sample. These findings strongly suggest that the BKT-BF-xST ceramic system holds exceptional promise for applications in pulse power capacitor applications. Graphical abstract Download : Download high-res image (244KB) Download : Download full-size image

Phosphate Ba5P6O20 (BPO) with short absorption edge is a promising phosphor host material. However, the nonequivalent replacement of trivalent rare earth activators for bivalent barium generally induces the defects, which is unfavorable for efficient fluorescence. Meanwhile, the diverse Ba2+ coordination fields bring the challenge for determining the occupancy sites of activator ions. In this study, the alkali charge compensators A+ (A = Li, Na, and K) are co-doped into BPO:Eu3+ to enhance significantly red-emitting properties. Through employing the theoretical and spectral methods, the multiple Eu3+ occupancy sites are revealed in detail. The luminescent intensity is improved by 120 %, 149 %, and 164 %-fold for Li+, Na+ and K+ co-doping, separately. The luminescent efficiency and thermal stability are also remarkably enhanced. Additionally, the indoor and plant lighting applications for the resulting phosphor are investigated, displaying satisfactory performance. The study manifests that the title material compensated with alkali metal ions A+ is expected to become a red-emitting candidate for multifunctional lighting utilizations. Graphical abstract Download : Download high-res image (375KB) Download : Download full-size image

Multifunctional metal-based materials have excellent electromagnetic interference (EMI) shielding effectiveness (SE) and soft magnetism in the military application. In pursuit of advancing multifunctional materials, particularly those metal-based materials exhibiting superior printability, soft magnetism and EMI SE. These endeavors encounter numerous challenges, with specific difficulties arising in printability and microstructure regulation. Herein, aiming to improve the soft magnetism and electromagnetic shielding performance of multifunctional alloys, a new FeCo-based alloy with different content of La2O3, Y2O3, Nd2O3 rare earth oxide, and rare earth Gd co-incorporation was prepared by laser multilayer cladding. Results show that the multifunctional FeCo-based alloys with optimized rare earth addition of La2O3, Y2O3, Nd2O3, and Gd exhibit highly super electromagnetic shielding property. Equal weight proportion of rare earth additions is key to a superior EMI shielding effectiveness of 96 dB at 23.9 GHz with the highest saturation magnetization (217.4 emu/g), which exceeds the quality standards in military applications. The discovery that in-situ generation of an ultrafine special α-Fe structure, encompassing a variety of rare earth compound nanoparticles and sub-micron chain particles during alloy synthesis, is instrumental in substantially elevating their electromagnetic shielding efficacy. The enhancement of soft magnetic properties and EMI shielding performance in the laser-clad multifunctional alloys can be attributed to a synergistic interplay between increased magnetic moments, dielectric and ohmic losses, and the unique refined α-Fe microstructure. This research presents innovative theoretical frameworks and technical strategies for the formulation of rare earth-enriched multifunctional alloys with EMI shielding properties, utilizing laser cladding technology. Graphical abstract Download : Download high-res image (341KB) Download : Download full-size image

Corneal endothelial dysfunctions are a significant cause of blindness. Corneal endothelial cell (CEC) transplantation presents a promising avenue for the treatment in clinics. However, it remains a formidable challenge to enhance the efficiency of cell delivery, as well as facilitate favorable cell attachment and integration with the host tissues. In this study, through incorporating superparamagnetic nanoparticles into hyaluronic acid (HA), a convenient and injectable magnetic HA gel system for efficient CEC delivery is innovated. This magnetic gel system exhibits favorable shear-shinning and superparamagnetic property, and advantageous characteristics of maintaining cell viability; moreover, it displays excellent capability of cell-concentrating and precise localization; furthermore, in vivo experiments confirms its outstanding ability of efficient cell delivery and attachment, suggesting a promising approach of cell precise delivery for the treatment of corneal endothelial dysfunctions. Graphical abstract Download : Download high-res image (252KB) Download : Download full-size image

Highlights • 3D printing of magnetic stimuli hydrogels has shown promise in low-resolution extrusion printing but faces limitations using high-resolution VAT polymerisation. • A new two-step capping method is developed for stabilising SPIONs into water-based photoresins that requires no agitation to maintain homogenous suspension during printing. • This methodology introduces added functionality and eliminates mechanical agitation to produce functional 3D printed hydrogels. 3D printing of magnetic stimuli hydrogels has shown promise in low-resolution extrusion printing but integrating superparamagnetic iron oxide nanoparticles (SPION) into water-based photo-resins has posed challenges. Rapid agglomeration and sedimentation of SPION in photo-resins require continuous mixing during printing, leading to uneven nanoparticle (NP) distribution and inconsistent magnetic actuation. Here, we optimise the use of citric acid (CA) and l-sodium ascorbate (LA) as capping agents on the SPION`s surface, before trialling them with photo-resins. Ultimately, we present a two-step approach to overcome these limitations, enabling high-resolution SLA-based 3D printing of hydrogels. By employing CA in both SPION and photo-resin preparation, we achieve a highly stable mixture that requires no agitation during printing, resulting in magnetically responsive hydrogels. This methodology can be applied to various photo-resin formulations, ensuring uniform NP distribution and enabling the 3D printing of stimuli-responsive materials for applications in soft robotics, aquatic micro-swimmers, and soft actuators. The breakthrough in stable and homogenous SPION-infused photo-resins has broad implications for tissue engineering, drug delivery, and regenerative medicine, offering novel biocompatible materials with resistance to stress and deformation. This approach can be extended to other NP with poor dispersion in hydrogels, paving the way for advanced functional materials in diverse applications. Graphical abstract Download : Download high-res image (158KB) Download : Download full-size image

The global demand for data storage and information security has risen to frightening levels. This is due to the global population`s paradigm shift toward digital technologies. Over the years, many materials have been explored with significant success and efficiency to drive a digital economy, however, research on stimuli-responsive materials (typically hydrogels) has been an interesting innovation in modern materials science and polymer chemistry. These developed materials are declared smart owing to their unique property and mode of design which incorporates stimuli-responsive moieties into the material structure. The external stimuli that alter the properties of the developed materials sensitive to them are largely grouped into the physical stimuli (e.g., magnetic field, light, temperature, mechanical stress, electrical field) and the chemical (e.g., pH, chemical reactions, ionic strength) stimuli. Thus, the review presents studies on stimuli-responsive hydrogel composite materials with an overview of their functional characteristics, reactions to various environmental stimuli, environmental implications, and potential uses in digital technologies. The scientific breakthrough in the production of stimuli-responsive hydrogel composites is an eye-opener for the development of novel material for improved data security, data authenticity, anti-counterfeiting devices, etc. Graphical abstract Download : Download high-res image (380KB) Download : Download full-size image

Tumor surgery poses significant challenges, including the presence of residual tumors, bacterial infections, and tissue defects, which contribute to high rates of tumor recurrence, low survival rates, and impaired wound healing. To address these issues, hydrogels, three-dimensional network structures formed through the crosslinking of natural or synthetic macromolecules, have emerged as promising solutions. By leveraging nanostructure-loaded hydrogels, different therapeutic modalities can be integrated into a single platform and significantly enhance antitumor effects and inhibit postoperative tumor metastasis and recurrence through synergistic therapeutic approaches. Furthermore, by incorporating therapeutic drugs and bioactive matrices, these nanostructure-loaded hydrogels can provide long-lasting antimicrobial and anti-inflammatory effects while also facilitating the regeneration of bones, skin, and adipose tissue. This comprehensive review aims to explore the design strategies, latest advancements in research, and therapeutic applications of nanostructure-loaded hydrogels in the integrated fields of antitumor therapy and tissue regeneration, including their use in photothermal/photodynamic therapy, chemodynamic therapy, chemotherapy, enhanced radiotherapy, and magnetic hyperthermia, as well as the synergistic therapeutic applications of the above methods. Finally, the challenges and potential solutions of nanostructure-loaded hydrogels in clinical therapy are also proposed. Graphical abstract Download : Download high-res image (159KB) Download : Download full-size image

Highlights • A convenient method for producing porous carbons with dual heteroatoms was reported. • Porous structure and heteroatom work synergistically to enhance catalytic activity. • Exceptional stability is shown by sustained high catalytic performance after 1-year storage. Development of affordable, efficient and metal-free heterogeneous catalytic systems has been a persistent challenge in academia and industry. Heteroatom-doped metal-free carbon materials are increasingly recognized as valuable heterogeneous catalysts, and if well-designed, can present comparable performance to, or even surpass transition metal-containing catalysts. Their physicochemical properties and structural characteristics are tunable in a wide range, plus being free of leakage problems of transition metal species into the environment. Herein, three types of hierarchically porous N/X co-doped carbon materials (X denotes B, P or S) were synthesized via using poly(ionic liquid)s (PILs) as carbon precursors and source of heteroatom dopants. The incorporation of sacrificial pore-inducing templating agents which created abundant edge defects, in combination with a heteroatom co-doping strategy, enhanced the number of active sites and their peroxidase-like catalytic activities. Comparison with only nitrogen single-doped porous carbons as reference demonstrated that co-doping with nitrogen and another heteroatom exhibits higher peroxidase-like activity and affinity towards substrates. Among the three types of heteroatom co-doped porous carbonaceous artificial enzymes, the N/B co-doped carbonaceous catalyst displayed the highest specific activities and Vmax values. These observations suggest a synergistic effect of the co-dopants, here N and B in the enzyme that holds a promising potential to further enhance peroxidase-like activity. Graphical abstract Download : Download high-res image (196KB) Download : Download full-size image