Nucleic acid (NA)-mediated vaccination has gained huge interest in recent years. Especially, DNA vaccines can provide long lasting immunity at a relatively low cost. Subcutaneous and intradermal injections are the...
Emerging new materials have always been key to building high-performance biosensors. Metal nanoclusters (MNCs) stabilized by water-soluble ligands, as promising and highly versatile sensing nanomaterials, have attracted considerable attention in recent years owing to their exceptional properties, including low toxicity, high sensitivity, improved selectivity, and excellent biocompatibility for diverse label-free chemical and biological detection applications. In this review, we briefly illustrate the main synthesis methods for water-soluble MNCs and then systematically and comprehensively summarize their applications in various detection fields, such as nucleic acids, proteins, small biomolecules, metal ions, and cancer cells. Through representative case examples, we elaborately highlight their sensing mechanisms, demonstrating that rationally designed MNC-based probes can achieve exceptionally low detection limits with wide linear dynamic ranges for metal ions, and can even reach ultrahigh sensitivity for biomolecules, underscoring their robust practical analytical potential. Finally, we outline the future development directions and challenges of MNCs in the detection field. We believe that this review will facilitate timely recognition of the importance of MNCs in biological detection and hopefully stimulate their future development.
Preparing photocatalysts in the form of thin films represents an efficient strategy for their recovery from target solutions.However, the origin of the low apparent photocatalytic performance observed in thin-film photocatalysts...
I-IV-VI semiconductor quantum dots (QDs) have attracted increasing attention owing to their tunable optoelectronic properties and low toxicity. Herein, Cu-Ag-Ge-S QDs were synthesized via a facile solution-phase method, enabling systematic tuning of both the bandgap energy and localized surface plasmon resonance (LSPR) through compositional control. Ag incorporation into the Cu-based lattice induced lattice expansion and suppressed Cu-related defects, resulting in significant modulation of the electronic structure. With increasing Ag content, the optical absorption edge and incident photon-to-current efficiency (IPCE) spectra exhibited pronounced red shifts, extending the photoresponse to approximately 970 nm. Photoelectrochemical measurements further revealed a transition from p-type to ambipolar behavior accompanied by shifts in photocurrent onset potential, consistent with the evolution of the electronic band structure. These results demonstrated that Ag incorporation effectively tailored the charge transport and photoresponse characteristics of the QDs. Furthermore, quantum dot-sensitized solar cells (QDSSCs) fabricated with Cu-Ag-Ge-S QDs of higher Cu content exhibited improved performance, in which the QDs prepared with Cu/(Cu + Ag) = 1.0 exhibited an optimal short-circuit current density (Jsc) of 4.9 mA cm-2 and an optimal power conversion efficiency (PCE) of 1.06%. This enhancement was attributed to the change in the electronic energy structure of the QDs with the Cu content. This work demonstrates the potential of composition-controlled Cu-Ag-Ge-S QDs as low-toxicity, Earth-abundant materials for near-infrared optoelectronic and solar energy conversion applications.
Hydrovoltaic power generation in porous conductors is often limited by the trade-off between strong wetting for ion activation and low internal resistance for efficient charge extraction. In this study, we engineered a dual-layer MgAl-layered double hydroxide (LDH) architecture on exfoliated graphene sheets (EGs) wrapped around melamine foam to enhance both interfacial charge separation and charge transport. Hydrophilic LDH strongly adsorbs onto oxygenated EG functionalities (-OH/-COOH), inducing flower-like growth that conformally covers the graphene network and blocks the EG-EG junctions, thereby increasing the electrical resistance. By contrast, the dual-layer design with a hydrophobic LDH base preserved continuous conductive pathways in the EG framework while limiting direct water contact at the bottom interface, reinforcing streaming-potential-driven ion-electron coupling under saline droplet activation. Moreover, the hydrophilic LDH cap amplified the output through its strong water uptake and ion adsorption capabilities, which intensified interfacial hydration. Multiscale microscopy and wetting/chemical analyses corroborated the distinct interfacial morphologies and biphilic contrast. Consequently, the dual-layer LDH/EG foam delivers a markedly boosted output, achieving currents up to ∼30 µA with pronounced power enhancement compared with both fully hydrophilic overcoated and LDH-free counterparts.
Hydrogen is a promising energy vector with the potential to become the cornerstone of sustainable energy systems with the support of green production, storage, and utilization technologies. Among the materials...
Oleylamine-coated gold ultrathin nanorods (AuUNR:OA), featuring an anisotropic morphology with a diameter of ~1.8 nm, exhibit exclusively the longitudinal mode of localized surface plasmon resonance (LSPR). However, reinforcing their structural...
We present a density functional theory investigation of pristine and doped (MgH2)n clusters (n = 2-4) as model systems that maximise nanoscale confinement effects, focusing on the distinct electronic regimes introduced by alkali (Li, Na, and K) and alkaline-earth (Be and Ca) dopants. The results reveal that monovalent substitution triggers a spin-selective electronic softening, with chemical hardness approaching zero in the minority spin channel accompanied by hydrogen-centred spin localisation and the emergence of weakly hydridic hydrogen sites. In contrast, divalent dopants preserve electronic rigidity and spin symmetry, maintaining the ionic coherence of the hydride framework. This difference demonstrates that by simply choosing the dopant valence, one can switch the electronic character of MgH2 nanoclusters between magnetically active/electronically soft and non-magnetic/electronically rigid states. The ability to tune the band gap and spin-dependent chemical hardness in a lightweight, Earth-abundant nanomaterial suggests possible routes toward tunable spin-dependent electronic responses in low-dimensional hydride nanomaterials, where controlled electronic softness and magnetic response are critical.
Rapid and effective bleeding control is critical for preventing circulatory shock and improving patient survival. Compared with conventional hemostatic materials such as gauze and patches, hydrogels have gained increasing attention...
To avoid the extensive use of toxic solvents and reduce energy consumption, an environmentally friendly method was employed to synthesize high-yield full-color carbon quantum dots (CDs) using p-phenylenediamine (PPD) and...
Natural herbal small molecules with remarkable supramolecular self-assembly behavior are particularly attractive in fabricating multifunctional biomaterials. Glycyrrhizic acid (GA), a natural food-grade triterpenoid saponin with inherent biological effects and excellent biocompatibility and biodegradability, exhibits hierarchical self-assembly in aqueous solutions, leading to the formation of two-dimensional nanofibrils and further a supramolecular gel network. The controllable GA self-assembly makes it highly suitable for the development of versatile functional biomaterials (e.g., nanoparticles and hydrogels). Herein, we first review the structural characteristics and self-assembly mechanism of GA in aqueous solutions, with particular emphasis on its stimuli-responsive assembly behavior. Subsequently, a systematic and comprehensive overview of the pathways for fabricating advanced biomaterials and the three major classes of GA-based supramolecular materials are presented. Finally, the carrier-free bioactive substances delivery, antibacterial efficiency, wound healing, and biosensing applications of GA-based multifunctional materials are summarized and highlighted. Future scientific challenges and opportunities are also discussed to provide insights into the rational design and development of next-generation GA-based multifunctional biomaterials for biomedical applications.
Layered two-dimensional halide double perovskites are often considered promising lead-free semiconductors because of their low bandgaps and strong optical absorption. Despite these properties, their use in high-performance broadband optoelectronic devices...
Desulfurization wastewater from coal-fired power plants contains high salinity and toxic heavy metals, posing significant environmental challenges. In this work, we developed an innovative solar membrane evaporation-crystallization system driven by...
Although the piezoelectric effect was discovered 146 years ago, its mechanisms have yet to be fully understood. To uncover the reasons for the thickness-dependent piezoelectric performance and to further validate...
MXenes, a rapidly expanding family of two-dimensional (2D) materials, hold great research interest for electromagnetic interference (EMI) shielding applications owing to their tunable surface chemistry and superior metallic conductivity. Here, using first-principles calculations, we investigate intrinsic vacancy defects in Ti3C2T2 monolayers and their effects on electronic structure, electrical conductivity and estimated EMI shielding performance. Surface Ti and C vacancies are shown to introduce localized states and band flattening around the Fermi level, resulting in a decrease in electrical conductivity. Different surface terminations (-OH, -Cl, -F, and -S) significantly modulate the defect formation energy and electronic transport properties, with calculated conductivities ranging from 4401 S cm-1 for Ti3C2O2 to 13 686 S cm-1 for Ti3C2S2. The calculated conductivity values correspond to estimated EMI shielding effectiveness exceeding 53 dB, while vacancy defects can decrease effectiveness due to the introduction of scattering centers. However, defect properties vary with termination groups and can even maintain effectiveness in some cases, with zero conductivity decrease for the Ti vacancy in Ti3C2(OH)2. This work provides atomic-level insight into how defects and surface terminations tune intrinsic electronic structure, conductivity and EMI shielding effectiveness, offering theoretical guidance for high-conductivity MXene films for EMI shielding applications.
Photocatalytic nitrate reduction to ammonia provides a sustainable route that integrates nitrogen-pollution remediation with green ammonia synthesis. However, the ammonia production efficiency of existing photocatalytic systems remains limited by insufficient light harvesting, severe recombination of photogenerated charge carriers, and inefficient surface adsorption and activation of nitrate. Herein, a surface electron-reservoir engineering strategy is proposed by anchoring zero-dimensional carbon quantum dots (CQDs) onto the surface of one-dimensional rod-like Bi19S27Br3 through a facile hydrothermal method, yielding CQDs/Bi19S27Br3 photocatalysts. Structural characterization studies demonstrate that the introduction of CQDs not only broadens the photoresponse range of Bi19S27Br3 but also enables CQDs to serve as surface electron reservoirs that accept and temporarily store photogenerated electrons from Bi19S27Br3 under illumination, thereby suppressing electron-hole recombination and improving the utilization efficiency of photogenerated electrons. Photocatalytic tests demonstrate that the optimized 5CQDs/Bi19S27Br3 achieves an NH3 production rate of 423.67 μmol g-1 h-1, with apparent quantum efficiencies of 0.24% and 0.17% under monochromatic irradiation at 380 and 400 nm, respectively. In situ FTIR results reveal that NO3- undergoes successive adsorption, stepwise deoxygenation, and proton-coupled electron-transfer processes on the surface of 5CQDs/Bi19S27Br3, ultimately being converted into NH4+via key intermediates such as *NO2, *NO, and *NH2OH.
Lead halide perovskite quantum dots (PQDs) have garnered considerable attention in the past decade owing to their remarkable optoelectronic characteristics; however, reports on their optical limiting performance in combination with graphene remain limited. In this work, we synthesised CsPbBr3 PQDs-reduced graphene oxide (rGO) composites with different weight percentages via a facile, room-temperature method under air atmospheric conditions. Structural, optical, and time-resolved spectroscopic analyses confirm strong electronic coupling between CsPbBr3 PQDs and rGO, indicating efficient charge transfer at the interface. The composites exhibit improved excited-state dynamics with faster carrier transfer compared to pristine CsPbBr3. A comparative study between thin films and liquid samples of CsPbBr3 PQDs was also carried out, assessing the effect of the material's form on its nonlinear absorption performance. Third-order nonlinear optical behaviour was investigated using Z-scan measurements with a 532 nm nanosecond pulsed laser. All of the samples displayed a reverse saturable absorption pattern involving two-photon absorption, along with enhanced optical limiting thresholds, highlighting the synergistic effect of perovskite-rGO nonlinear absorption. Notably, the CsPbBr3 PQDs-40% rGO composite showed the highest nonlinear absorption coefficient (2.27 × 10-10 m W-1) and the lowest optical limiting threshold (0.86 × 1012 Wm-2), demonstrating superior optical limiting performance. Interestingly, the material demonstrated optical limiting behaviour both in liquid and thin film phases. Our findings reveal that CsPbBr3 PQDs-rGO composites offer enhanced optical limiting compared to their individual counterparts, highlighting their potential for next-generation photonic protection devices. This work provides new insights into exploiting perovskite-carbon hybrid nanostructures as efficient optical limiters.
Catalyst morphology selection can effectively tune the performance of transition metal oxide heterogeneous catalysts by optimizing surface structure and defect chemistry. In this study, five distinct Co3O4 heterogeneous catalyst morphologies - nanochains, nanocubes, nanosheets, nanoplates and porous nanoplates - were synthesized using two chemical routes: hydrothermal synthesis with controlled reaction temperature and co-precipitation using bases of different strengths. Structural characterization confirmed the catalyst materials were phase-pure cubic spinel Co3O4, but that they possessed morphology-dependent differences in crystallinity, defect concentration, crystallite size, and porosity. The catalytic performance of the materials was evaluated for the selective oxidation of benzyl alcohol, where a pronounced morphology-dependent activity was observed. The five examined nanomaterial morphologies exposed different crystal facets, with the anisotropic Co3O4 nanochains preferentially exposing {111} planes being the most reactive. Co3O4 nanochains exhibited the highest catalytic activity and excellent selectivity, producing benzaldehyde as the sole product under the studied conditions. The enhanced performance is attributed to the combined effects of exposed {111} facets and the high density of accessible oxygen vacancies in the Co3O4 nanochains, which facilitate the redox cycle of cobalt active sites. Based on these observations, a plausible redox mechanism for the catalytic benzyl alcohol oxidation over Co3O4 is proposed. This work demonstrates how controlled morphology and surface structure can significantly influence and improve rational design of efficient metal oxide catalysts for selective oxidation reactions.
Trace sub-100 nm impurities in processing chemicals represent a major yield-limiting challenge for sub-10 nm semiconductor manufacturing because they are difficult to remove using conventional purification methods. Mechanical filtration is...
MXene/metal–organic framework (MOF) hybrids enable tunable electrode architectures and charge-storage kinetics, but synthesis–structure–electrochemical relationships remain insufficiently understood.
