Nano Research最新文献

Over the last two decades, small activating RNAs (saRNAs) have quickly moved from discovery to clinical trials. Characterized as 20 nucleotide long, double stranded RNA, saRNAs have the unique ability to increase gene transcription at the chromatin level. This therapeutic modality has great potential as a safe and redosable alternative to gene therapy by increasing target protein expression without changing the genetic sequence. We describe the successful in vivo saRNA delivery vectors and found that similar to small interfering RNA (siRNA) and mRNA targeting tissues outside the liver works best at the end of a needle. We highlight nanoparticle vectors and RNA-conjugates, where some success has been reported for non-hepatic delivery of saRNA-aptamers.

Silicon monoxide (SiO) is widely recognized as a promising anode material for next-generation lithium-ion batteries. Owing to its metastable amorphous structure, SiO exhibits a highly complex degree of crystallization at the microscopic level, which significantly influences its electrochemical behavior. As a consequence, accurately regulating the crystallization of SiO, and further establishing the relationship between crystallinity and electrochemical performance are very critical for SiO anodes. In this article, carbon-coated SiO materials with different crystallinity degrees were synthesized using lithium hydroxide monohydrate (LiOH·H₂O) as a structural modifier to reveal this rule. Additionally, moderate amount of LiOH·H₂O addition results in the forming of an oxygen-rich shell, which effectively inhibits the inward migration of oxygen atoms on the SiO surface and suppresses volume expansion. However, the crystallinity of SiO will gradually enhance and the crystalline phase appears with increasing the amount of LiOH·H₂O, which will generate a deteriorative Li⁺ diffusion kinetic. After balancing the above two contradictions, a mass fraction of 1% LiOH·H₂O for the additive yielded SiO@C-1, characterized by optimal crystallinity. SiO@C-1 demonstrates exceptional long-cycle stability with 74.8% capacity retention after 500 cycles at 1 A·g⁻¹. Furthermore, it achieves a capacity retention of 52.2% even at a high density of 5 A·g⁻¹. This study first reveals the relationship between SiO crystallinity and electrochemical performance, which efficiently guides the design of high-performance SiO anodes.

Solid-state polymer electrolytes (SPEs) are candidate schemes for meeting the safety and energy density needs of advanced lithium-based battery because of their improved mechanical and electrochemical stability compared to traditional liquid electrolytes. However, low ionic conductivity and side reactions occurring in traditional high-voltage lithium metal batteries (LMBs) hinder their practical applications. Here, amino-modified metal-organic frameworks (UiO-66-NH₂) with abundant defects as multifunctional fillers in the polyurethane based SPEs achieve the collaborative promotion of the mechanical strength and room temperature ionic conductivity. The surface modified amino groups serve as anchoring points for oxygen atoms of polymer chains, forming a firmly hydrogen-bond interface with polycarbonate-based polyurethane frameworks. The rich interfaces between UiO-66-NH₂ and polymers dramatically decrease the crystallization of polymer chains and reduce ion transport impedance, which markedly boosted the ionic conductivity to 2.1 × 10⁻⁴ S·cm⁻¹ with a high Li⁺ transference numbers of 0.71. As a result, LiFePO₄∣SPEs∣Li cells exhibit prominent cyclability for 700 cycles under 0.5 C with 96.5% capacity retention. The LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622)∣SPEs∣Li cells deliver excellent long-term lifespan for 260 cycles with a high capacity retention of 91.9% and high average Coulombic efficiency (98.5%) under ambient conditions. This simple and effective hybrid SPE design strategy sheds a milestone significance light for high-voltage Li-metal batteries.

Nanomaterials have revolutionized the battery industry by enhancing energy storage capacities and charging speeds, and their application in hydrogen (H₂) storage likewise holds strong potential, though with distinct challenges and mechanisms. H₂ is a crucial future zero-carbon energy vector given its high gravimetric energy density, which far exceeds that of liquid hydrocarbons. However, its low volumetric energy density in gaseous form currently requires storage under high pressure or at low temperature. This review critically examines the current and prospective landscapes of solid-state H₂ storage technologies, with a focus on pragmatic integration of advanced materials such as metal-organic frameworks (MOFs), magnesium-based hybrids, and novel sorbents into future energy networks. These materials, enhanced by nanotechnology, could significantly improve the efficiency and capacity of H₂ storage systems by optimizing H₂ adsorption at the nanoscale and improving the kinetics of H₂ uptake and release. We discuss various H₂ storage mechanisms—physisorption, chemisorption, and the Kubas interaction—analyzing their impact on the energy efficiency and scalability of storage solutions. The review also addresses the potential of “smart MOFs”, single-atom catalyst-doped metal hydrides, MXenes and entropy-driven alloys to enhance the performance and broaden the application range of H₂ storage systems, stressing the need for innovative materials and system integration to satisfy future energy demands. High-throughput screening, combined with machine learning algorithms, is noted as a promising approach to identify patterns and predict the behavior of novel materials under various conditions, significantly reducing the time and cost associated with experimental trials. In closing, we discuss the increasing involvement of various companies in solid-state H₂ storage, particularly in prototype vehicles, from a techno-economic perspective. This forward-looking perspective underscores the necessity for ongoing material innovation and system optimization to meet the stringent energy demands and ambitious sustainability targets increasingly in demand.

The potential of personal cooling technologies in reducing air conditioning energy consumption and enhancing human thermal comfort is substantial. This review focuses on recent advancements in hierarchical structure design for innovative cooling textiles. Beginning with insights into fundamental heat transfer processes between the human body, textile, and the surroundings, we uncover key control mechanisms. Then the advanced hierarchical structure designs enabling effective radiation, sweat evaporation, conduction management, and integration of cold energy sources for realizing effective human body cooling are systematically summarized. Additionally, we explore multifunctional designs beyond cooling, including switchable cooling-heating and sensing. Finally, we engage in discussions on unifying cooling performance tests and additional multiple requirements to make strides toward practical applications. This review is anticipated to be a valuable resource, providing the scientific and industrial communities with a quick grasp of past advancements, current challenges, and future directions in achieving effective human body cooling.

To ensure the green and sustainable advancement of hydrogen energy, there is a critical need for the development of a cost-effective catalyst to address the sluggish kinetics of water electrolysis under alkaline conditions. An approach to achieve this is by constructing ultrathin Pt shell-structured catalysts that offer enhanced electrocatalytic hydrogen evolution reaction performance through modulation of the inner core while minimizing costs. Herein, an ultrathin Pt shell catalyst with an inner core consisting of a PtNi face-centered cubic and hexagonal-close-packed mixed-phase interface (named PtNi-mix) is synthesized through a pre-synthesis method followed by post-acid etching process. Encouragingly, the PtNi-mix catalyst only requires 12.9 mV overpotential to achieve a current density of 10 mA·cm^-2 in 1 M KOH, which is much lower than that of the commercial 20 wt.% Pt/C catalyst (71.2 mV). Also, it possesses a high mass activity (7.2 A·mg^-1) at an overpotential of 70 mV, which is 9 times higher than that of the commercial 20 wt.% Pt/C catalyst. Additionally, the performance of the PtNi-mix catalyst remains almost unchanged after 10,000 cyclic voltammetry tests, indicating that the catalyst exhibits excellent stability.

g-C₃N₄ emerges as a promising metal-free semiconductor photocatalyst due to its cost-effectiveness, facile synthesis, suitable visible light response, and robust thermal stability. However, its practical application in photocatalytic hydrogen evolution reaction (HER) is impeded by rapid carrier recombination and limited light absorption capacity. In this study, we successfully develop a novel g-C₃N₄-based step-scheme (S-scheme) heterojunction comprising two-dimensional (2D) sulfur-doped g-C₃N₄ nanosheets (SCN) and one-dimensional (1D) FeCo₂O₄ nanorods (FeCo₂O₄), demonstrating enhanced photocatalytic HER activity. The engineered SCN/FeCo₂O₄ S-scheme heterojunction features a well-defined 2D/1D heterogeneous interface facilitating directed interfacial electron transfer from FeCo₂O₄ to SCN, driven by the lower Fermi level of SCN compared to FeCo₂O₄. This establishment of electron-interacting 2D/1D S-scheme heterojunction not only facilitates the separation and migration of photogenerated carriers, but also enhances visible-light absorption and mitigates electron-hole pair recombination. Band structure analysis and density functional theory calculations corroborate that the carrier migration in the SCN/FeCo₂O₄ photocatalyst adheres to a typical S-scheme heterojunction mechanism, effectively retaining highly reactive photogenerated electrons. Consequently, the optimized SCN/FeCo₂O₄ heterojunction exhibits a substantially high hydrogen production rate of 6303.5 µmol·g⁻¹·h⁻¹ under visible light excitation, which is 2.4 times higher than that of the SCN. Furthermore, the conjecture of the S-scheme mechanism is confirmed by in situ XPS measurement. The 2D/1D S-scheme heterojunction established in this study provides valuable insights into the development of high-efficiency carbon-based catalysts for diverse energy conversion and storage applications.

Aerogel-based composites hold promising application prospects as potential electromagnetic wave (EMW) absorption materials, yet the construction of such materials with ingenious microstructures, appropriate magnetic/dielectric multi-components, and integrated multifunctionality remains considerably challenging. Herein, a multicomponent Co/MnO/Ti₃C₂T_x MXene/rGO (CMMG) hybrid aerogel featured with three-dimensional (3D) vertical directional channel architecture is reported. Benefiting from the synergistic effect arising from the 3D conductive networking structure, diverse heterogeneous interfaces, magnetic/dielectric multicomponent, and multiple loss pathways, the optimized CMMG-2 aerogel delivers fascinating EMW absorption capabilities, characterized by a minimal reflection loss (RL_min) of −77.41 dB and an effective absorption bandwidth (EAB) of 6.56 GHz. Additionally, the remarkable hydrophobicity, exceptional thermal insulation capabilities, and outstanding photothermal properties of CMMG-2 aerogel make it highly promising for multiple application in diverse and demanding environments. Interestingly, the distinctive pore structure of hybrid aerogel also allows it for sensitive and reliable detection of electrical signals caused by pressure changes and human motion. Thus, this research provides a viable design strategy for the development of lightweight, efficient, and multifunctional aerogel-based EMW absorption materials for various application scenarios.

Heterogeneous advanced oxidation processes (AOPs) based on non-radical reactive species are considered as a powerful technology for wastewater purification due to their long half-lives and high adaptation in a wide pH range. Herein, we fabricate surface Co defect-rich spinel ZnCo₂O₄ porous nanosheets, which can generate ≡Co^IV=O and ¹O₂ over a wide pH range of 3.81–10.96 by the formation of amphoteric ≡Zn(OH)₂ in peroxymonosulfate (PMS) activation process. Density functional theory (DFT) calculations show Co defect-rich ZnCo₂O₄ possesses much stronger adsorption ability and more electron transfer to PMS. Moreover, the adsorption mode changes from terminal oxygen Co–O–Co to Co–O, accelerating the polarization of adjacent oxygen, which is beneficial to the generation of ≡Co^IV=O and ¹O₂. Co defect-rich ZnCo₂O₄ porous nanosheets exhibit highly active PMS activation activity and stability in p-nitrophenol (PNP) degradation, whose toxicity of degradation intermediates is significant reduction. The Co defect-rich ZnCo₂O₄ nanosheet catalyst sponge/PMS system achieved stable and efficient removal of PNP with a removal efficiency higher than 93% over 10 h. This work highlights the development of functional catalyst and provides an atomic-level understanding into non-radical PMS activation process in wastewater treatment.

In the past decade, ferroelectric materials have been intensively explored as promising photocatalysts. An intriguing ability of ferroelectrics is to directly sperate the photogenerated electrons and holes, which is believed to arise from a spontaneous polarization. Understanding how polarization affects the photocatalytic performance is vital to design high-efficiency photocatalysts. In this work, we report a size effect of ferroelectric polarization on regulating the photocatalytic overall water splitting of SrTiO₃/PbTiO₃ nanoplate heterostructures for the first time. This was realized hydrothermally by controlling the thickness and thus spontaneous polarization strength of single-crystal and single-domain PbTiO₃ nanoplates, which served as the substrate for selective heteroepitaxial growth of SrTiO₃. An enhancement of 22 times in the photocatalytic overall water splitting performance of the heterostructures has been achieved when the average thickness of the nanoplate increases from 30 to 107 nm. A combined experimental investigation revealed that the incompletely compensated depolarization filed is the dominated driving force for the photogenerated carrier separation within heterostructures, and its increase with the thickness of the nanoplates accounts for the enhancement of photocatalytic activity. Moreover, the concentration of oxygen vacancies for negative polarization compensation has been found to grow as the thickness of the nanoplates increases, which promotes oxygen evolution reaction and reduces the stoichiometric ratio of H₂/O₂. These findings may provide the opportunity to design and develop high-efficiency ferroelectric photocatalysts.