Rare Metals最新文献

The commercialization of perovskite solar cells (PSCs) is significantly hindered by intrinsic defects in solution-processed polycrystalline films, which promote nonradiative recombination and accelerate material degradation, coupled with environmental issues arising from the potential leaching of toxic lead (Pb) species upon device failure. This work presents a multifunctional molecular interfacial engineering strategy by incorporating 4-chlorophenyl dichlorophosphate (4-CP) to optimize the SnO₂ electron transport layer/perovskite interface. The triple functionality of 4-CP enables synergistic defect passivation, crystallization modulation, and Pb immobilization. Owing to electronegativity differences, the phosphate groups in 4-CP effectively passivate SnO₂ surface oxygen vacancies via strong coordination, while the expelled hydrophobic phenyl rings and C–Cl bonds regulate perovskite grain growth and anchor Pb²⁺. The optimized device achieves a power conversion efficiency (PCE) of 25.25% with increased stability. Remarkably, 4-CP modification reduces Pb leakage by 89%; the Pb²⁺ leaching concentration from 4-CP-modified devices lower than 30 ppb which is far below the safety threshold (50 ppb) of China's Environmental Quality Standards for Surface Water (GB 3838–2002). Moreover, the 4-CP-modified devices retained 92% of its initial PCE after rigorous aging (25 °C, 85% RH, 1000 h), demonstrating exceptional operational stability. This multifunctional interface engineering approach provides a groundbreaking pathway toward high-performance, eco-conscious PSCs.

Graphical Abstract

This study introduces a rationally designed trifunctional molecule (4-CP) that synergistically passivates SnO₂/perovskite interfacial defects, guides perovskite crystallization, and immobilizes toxic Pb²⁺, achieving a record PCE of 25.25% with 89% Pb leakage reduction and exceptional thermal stability, redefining multifunctional molecular engineering for high-performance and eco-safe perovskite solar cells.

Cancer is a major ongoing threat to human survival and health worldwide due to its high incidence and mortality. Recently, gas therapy has attracted extensive attention as a novel cancer treatment with good biosafety, high efficiency, and few side effects. Given the low solubility and nontargetability of gas molecules, however, various delivery materials have been developed as gas carriers to increase the therapeutic effects of gas treatment. Nanocarriers based on metallic materials have attracted extensive attention because of their stability and biocompatibility. They can undergo gradual degradation to enable the sustained release of bioactive ions, which exert multiple functions, including interference with tumor cell metabolism and immune regulation. This review focuses on the therapeutic mechanisms of various gases used in tumor therapy, including nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H₂S), hydrogen (H₂), oxygen (O₂), and sulfur dioxide (SO₂), and related research progress. The targeted delivery of gas donors and the controlled release of reactive gas are achieved through the structural design and functional optimization of gas delivery metallic nanomaterials, which are regulated by multiple exogenous or endogenous stimuli. Furthermore, synergistic combinations of gas therapy with other cancer treatment modalities, such as radiotherapy (RT), phototherapy, and ultrasonic therapy, are comprehensively summarized. Finally, the existing challenges and potential development possibilities of gas-mediated cancer therapy based on metallic nanomaterials are discussed. This review provides insight into the potential development of antitumor strategies to promote the controlled release of gas molecules on-demand for the effective eradication of tumor tissues.

Graphical abstract

Transition metal selenides have been considered as prospective anode materials for advanced lithium-ion batteries due to the features of high theoretical capacity, environmentally friendly and abundant resource reserves. Nevertheless, the long-term cycling stability property is limited owing to electrode structure disruption caused by huge volume expansion during cycling and the poor rate capability results from their poor intrinsic conductivity. Herein, the hollow selenium/ferromanganese selenide nanospheres (Se/MnFe₂Se₄) were synthesized via a SiO₂-assisted template method, which was decorated with 3D porous graphene aerogel with satisfactory structure and mechanical properties, forming the Se/MnFe₂Se₄/rGO composites. The prepared composites offered multiple advantages for enhancing lithium storage. First, hollow nanospheres can reduce ion/electron diffusion pathways, widen the surface area, and alleviate partial volume expansion. Meanwhile, Se was introduced into the composites to improve their conductivity and provided extra capacity by participating in the charging/discharging process. Besides, 3D porous graphene aerogels (rGO) provided more active sites, which improved the conductivity, shortened the transport path of ions and electrons, and effectively alleviated the stress concentration due to volume changes. The Se/MnFe₂Se₄/rGO composites showed stable cycling performance of 961.3 mAh g⁻¹ at 0.1 A g⁻¹ after 200 cycles and 638.7 mAh g⁻¹ at 1.0 A g⁻¹ after 2500 cycles. This work provided a novel anode electrode with a satisfactory electrochemical performance improvement strategy, which would promote the development of high-performance LIBs and other energy storage devices.

Graphical abstract

Accelerating industrialization introduces polymetallic contamination via industrial wastewater, excessive agrochemicals, and ore processing. These activities result in severe health consequences. Bioabsorption is a green and sustainable method for synthesizing electrode materials, enabling the transformation of biomass into high-value materials and promoting a circular economy. In this study, thermodynamic phase diagram calculations and the “Alloying” material design concept are integrated into this method, facilitating the remediation and recycling of multi-heavy metal composite pollutants in the environment and overcoming the electrochemical performance limitations of single-metal materials. The alloy oxide/carbon composite electrode is successfully fabricated through a synergistic approach combining thermodynamic phase diagram calculations, KOH-assisted high-temperature pyrolysis, and biomass-derived spatial confinement. This study elucidates the positive role of the alloy oxides prepared by this method in enhancing electrochemical performance. Specifically, the composite material exhibits a high specific surface area of 1,644.341 m² g⁻¹ and a high degree of graphitization of I_D/I_G = 1.14, which delivers a specific capacitance of 616 F g⁻¹ at 0.5 A g⁻¹ and a capacity retention rate of 89.76% after 15,000 cycles. Specifically, the composite material exhibits a high specific surface area of 1644.341 m² g⁻¹ and a high degree of graphitization of I_D/I_G = 1.14, which delivers a specific capacitance of 616 F g⁻¹ at 0.5 A g⁻¹ and a capacity retention rate of 89.76% after 15,000 cycles. This work drives energy transformation through innovative material design, contributing a key solution for developing sustainable, high-performance, and recyclable green energy storage systems.

Graphical abstract

Layered oxide cathode materials have attracted significant attention due to their high energy density. However, their practical commercialization in sodium-ion batteries has been hindered by drawbacks such as poor air stability and cycle performance. Herein, we present a simple strategy to address these obstacles through Ti doping. Interestingly, Ti doping can increase the Na layer spacing while decreasing the transition metal layer spacing. The modified interlayer space ensures a greater Na⁺ diffusion coefficient and improved rate performance. Moreover, the high-spin Mn³⁺ content decreases after Ti doping, which mitigates the Jahn–Teller effect and improves structural stability. As a result, the Na_0.55Ni_0.1Fe_0.1Mn_0.65Ti_0.15O₂ cathode material delivers a capacity retention of 77.11% after 150 cycles at 1C, which is much higher than 55.02% of Na_0.55Ni_0.1Fe_0.1Mn_0.8O₂. Meanwhile, the air stability evaluation reveals that carbon dioxide and water promote the formation of the hydrate phase. Ti doping can inhibit the exchange of H⁺ and Na⁺, as well as the formation of residual sodium species. Furthermore, the electrochemical performance deterioration caused by the water will be alleviated. These findings provide valuable insight into the development of layered oxide cathode materials with needed cycling performance and air stability for the commercialization of SIBs.

Photocatalytic hydrogen evolution, a promising clean energy conversion technology, faces efficiency limitations due to the mismatched timescales between sub-picosecond bulk photocarrier recombination and microsecond-scale surface reaction. Herein, a dual-strategy involving selenium decoration and NiS_x cocatalyst loading was proposed to ameliorate the carrier dynamics bottleneck in CdS-based photocatalysts. The in situ loading of NiS_x cocatalysts established an interfacial built-in electric field (BIEF) that enabled spatially oriented carrier separation and transfer, while the selenium modification optimized the light absorption range and Fermi energy level, obtaining an increase in the photocarrier concentration and further modulated the BIEF. Femtosecond transient absorption spectroscopy revealed a dual-channel carrier dynamics enhancement mechanism that BIEF-driven directional charge migration synergistically coupled with NiS_x-mediated holes trapping. This synergistic effect achieved an approximately tenfold enhancement of hydrogen evolution rate (461.71 μmol h⁻¹) relative to that of bare CdS under visible light (> 420 nm). This study elucidated the regulatory mechanism of element decoration and cocatalyst loading on carrier dynamics, providing an insight for designing high-performance photocatalysts.

The development of advanced energy-storage systems and renewable energy technologies to meet the energy demands of automotive and consumer electronics is driving the integration of supercapacitors as critical components in these applications. This study explored the effect of incorporating dual metal salts (Sn and Zn) into carbon nanofibers (CNFs) on the supercapacitor performance. The surface-modified Sn-ZnO@CNF was synthesized using a self-template strategy, wherein zinc ions embedded in the nanofibers acted as precursors to develop thorny zeolitic imidazolate framework (ZIF) structures on the fiber surface. Furthermore, surface treatment with 2-methylimidazole (2MI) successfully increased the electrochemically active surface area (ECSA) from 902 to 2029 cm² g⁻¹, increasing the areal capacitance by approximately 55% in a potential window of 0–1.6 V. This composite electrode achieved a maximum specific capacitance of 1.31 F cm⁻² at a current density of 2 mA cm⁻², and it retained 90% of its initial capacitance after 30,000 charge–discharge cycles.

Graphical abstract

Photocatalytic CO₂ reduction using solar energy offers a promising path to carbon neutrality, with ZnO as a favored semiconductor due to its abundance, favorable band alignment, and eco-friendliness. However, challenges such as high carrier recombination, limited light absorption, and poor CO₂ adsorption limit its performance. To overcome these issues, an Ohmic contact heterostructure strategy is proposed. A theoretical screening of five noble metals (Ag, Pd, Ir, Au and Pt) for forming Ohmic contact metal–semiconductor heterostructures with ZnO was conducted, followed by experimental validation. Among these, the Au/ZnO heterostructure, with an appropriate Fermi level difference (Δ(Ф_ZnO—Ф_metal)) of 2.02 eV, achieved the highest CO yield of 28.66 μmol g^–1 h⁻¹, significantly outperforming than other Metal/ZnO combinations. Further investigation of Au/ZnO revealed that the Ohmic contact enhances photogenerated carrier separation, while Au nanoparticles serve as active sites and promote key reactions, including CO₂ adsorption, *COOH formation, and *CO desorption, leading to improved CO₂ reduction efficiency. This work provides valuable insights into the design of high-performance photocatalysts based on Ohmic contact heterostructures, offering potential solutions for energy and environmental challenges.