Rare Metals最新文献

The electromagnetic field coupling between two kinds of noble metal nanoparticles endows high surface-enhanced Raman scattering (SERS) activity but is accompanied by uneven hot spots. Using two-dimensional semiconductors with localized surface plasmon resonance (LSPR) effects instead of one of the noble metal components can effectively improve uniformity. Hence, the Ag nanoparticles (Ag NPs) loaded MoO_3−x nanoflowers (Ag/MoO_3−x) were engineered to exploit dual-plasmonic coupling and realize the trace detection of aldehyde volatile organic compounds (VOCs) gas. The finite-difference time-domain (FDTD) simulation results proved that there is an obvious electromagnetic field coupling effect between Ag NPs and MoO_3−x semiconductors, which can amplify the molecular dipole moment significantly. The chemical enhancement mechanism in the Ag/MoO_3−x substrate was clarified by band structure analysis, in which the free electrons accumulated at the bottom of the conduction band of the MoO_3−x semiconductor can promote the charge transfer process between Ag/MoO_3−x and the 4-aminothiophenol (4-ATP) molecule. Moreover, the electron delocalization of 4-ATP molecule was enhanced after being absorbed on Ag/MoO_3−x nanoflowers, facilitating the charge transfer between 4-ATP and Ag/MoO_3−x substrate effectively. Importantly, using the 4-ATP molecule as a probe, the trace detection of a variety of aldehyde VOCs gas was realized by Ag/MoO_3−x substrate with a low limit of detection (LOD) of 10 ppb. This work provided a new idea for the design of noble metal-plasmonic semiconductor heterostructure substrates.

Graphical abstract

Immunogenic cell death (ICD) represents a crucial mechanism in cancer therapy, providing a pathway to trigger antitumor immune responses. Recent advancements in understanding and applying ICD for lung cancer therapy have identified traditional chemotherapy agents as potent ICD inducers. Despite their efficacy, the systemic toxicity and potential for inducing drug resistance limit their clinical application. This study introduces a novel approach utilizing ferritin-based nanocarriers [HFn(+)] for the targeted delivery of doxorubicin (DOX), combined with CpG oligodeoxynucleotides as an immune adjuvant, to enhance the immunogenicity and therapeutic efficacy against lung cancer. The engineered HFn(+) nanocarriers exploit the tumor-targeting ability of ferritin, capitalizing on its preferential uptake via transferrin receptor 1 (TfR1) overexpression on tumor cells. We comprehensively evaluate the preparation, characterization, and in vitro and in vivo efficacy of pHFn(+)@CpG/DOX complexes. The study confirms the potent antitumor activity of pHFn(+)@CpG/DOX in a lung cancer model, presenting a promising strategy for combined tumor immunotherapy with minimal systemic toxicity. This approach not only underscores the potential of nanocarrier-based drug delivery systems in cancer therapy but also opens new avenues for developing more effective and targeted cancer treatment modalities.

Graphical Abstract

The electrochemical conversion of nitrate, commonly found in industrial effluents and contaminated groundwater, into ammonia offers a sustainable strategy for both wastewater remediation and ammonia production. However, most existing catalysts exhibit limited activity and stability, particularly under industrial-level current density. Here we present a straightforward hydrothermal–calcination method to in situ fabricate Cu-doped Co₃O₄ nanoneedle arrays on three-dimensional porous copper foam (Cu-Co₃O₄/CF). The resulting electrode delivers an industrial-scale current density of ~ 1000 mA cm⁻², a high NH₃ yield rate of 58.4 mg h⁻¹ cm⁻², and a Faradaic efficiency of 98.3% at −0.5 V versus RHE. The outstanding performance under high current density highlights the significant practical potential of Cu-Co₃O₄/CF for large-scale applications. Density functional theory (DFT) calculations combined with experimental analysis demonstrate that Cu incorporation optimizes NO₃⁻ adsorption energy. More importantly, the doping of Cu accelerates the kinetics of the Volmer step (H₂O → *H + *OH), which provides protons for the hydrogenation pathway. This promotes the selective formation of NH₃ during the electrochemical nitrate reduction reaction (NO₃RR). Overall, this work provides fundamental insights into designing efficient transition metal oxide catalysts for nitrate valorization.

Graphical abstract

The Na₄Fe₃(PO₄)₂P₂O₇ (NFPP) has considered as a very attractive cathode material for Na-ion batteries mainly due to its cheap price and high security. Its low electron transfer rate is usually improved by coating a layer of hard carbon, which however exhibits a low graphitization degree because of the relatively low NFPP synthesis temperature (~ 500 °C). In this study, a highly-conductive hybrid carbon has been employed to accelerate redox reaction kinetics of NFPP by modulating electronic structure for achieving high-power Na-ion batteries. The hybrid carbon is derived from the mixed polyethylene glycol (PEG) and glucose, in which the low ether bond energy (~ 340 kJ mol⁻¹) of PEG facilitates the free radical generation during pyrolysis with high graphitization degree while glucose improves the uniformity of the carbon coating. As a result, the optimized cathode exhibits a very high reversible capacity of 90.8 mAh g⁻¹ at 20C within 2.0–4.0 V with 85.3% capacity retention after 10,000 cycles, highlighting huge application potentials in two-wheeled electric vehicles, backup energy storage, and so forth.

Graphic Abstract

Nickel-based catalysts display promising potential in integrated hydrogen production through methanol electrooxidation (MOR). The unavoidable self-oxidation from Ni(OH)₂ to NiOOH severely restricts their MOR performance. To inspire the progress of MOR before self-oxidation of Ni species by altering reaction pathways, a heterostructured Ni–WO₂ catalyst is constructed to follow the direct electrooxidation pathway of methanol. In-situ/ex-situ characterization techniques combined with density functional theory calculations reveal the constructed Ni–WO₂ heterostructure alters the electronic structure of Ni site. It’s found Ni–Ni bond in Ni–WO₂ becomes longer and the electrons transfer from Ni sites to W sites. This results in upshifted d band center of Ni site and its closing to the Fermi energy level, which optimizes the CH₃OH adsorption and the deprotonation of *CH₃O into *CH₂O in potential-determining step. Moreover, the formed asymmetric adsorption sites increase the polarity of the methanol and the intermediate. As expected, CH₃OH molecule is highly converted into HCOOH via direct electrooxidation pathway. This obtained Ni–WO₂ exhibits superior MOR activity with high peak current density of 325.26 mA cm⁻² and performs long term of 90 h at 10 mA cm⁻² in hydrogen production. This work provides an important guidance for designing efficient Ni-based samples for direct electrooxidation of methanol.

Graphical abstract

Aqueous zinc-tellurium (Zn-Te) batteries have garnered much attention due to their inherent safety and high specific capacity. Unfortunately, the problem of low utilization and severe volume expansion represents a significant obstacle to the development of aqueous Zn-Te batteries. Herein, a synergistic defect engineering and gradient pore structure strategy is proposed to construct tellurium nanoclusters/carbon composite cathode materials (DP-C/Te) for high-performance aqueous Zn-Te batteries. The gradient pore structure supplies confinement spaces that restrict crystalline tellurium formation, facilitating high-activity tellurium nanoclusters and enhancing structural stability. A defect-rich structure can accelerate the migration and aggregation of tellurium, not only leading to the formation of tellurium nanoclusters but also boosting the redox reaction of aqueous Zn-Te batteries. Additionally, robust C–O bonds can further facilitate the interfacial electron transfer. Consequently, the DP-C/Te cathode for aqueous zinc-tellurium batteries demonstrates sufficient specific capacity (481.75 mAh g⁻¹ at 0.1 A g⁻¹), superior rate performance (114 mAh g⁻¹ even at 3 A g⁻¹) and reliable cycling stability (81% capacity retention at 1 A g⁻¹ after 1100 cycles). Furthermore, this work offers a promising perspective for high-performance aqueous Zn-Te batteries.

Graphical Abstract

Zinc (Zn) and its alloys have emerged as promising candidates for biomedical materials, owing to their controlled degradation kinetics, intrinsic biocompatibility, and the release Zn²⁺ ions which are known to promote bone regeneration and tissue healing. Despite their potential, the widespread clinical adoption of Zn alloys has been hindered by insufficient mechanical properties, design limitations of traditional manufacturing, and limited clinical validation. Recent advances in additive manufacturing (AM), particularly laser powder bed fusion (LPBF), are revolutionizing the production of Zn alloy implants. LPBF enables unprecedented design freedom and accuracy, allowing the fabrication of patient-specific, geometrically-intricate and porous structures with unique functionality that are previously unattainable. This review aims to provide a comprehensive overview of the latest progress in LPBF processing of Zn alloys, focusing on structure design, fabrication, microstructural characteristics, and mechanical and biological properties—critical factors for real applications of functional implants, particularly in cardiovascular and orthopedic fields. Additionally, this review examines the role of post-processing treatments, such as heat treatments and surface modifications, in adjusting degradation rate, controlling Zn²⁺ ion release, and improving cell viability, proliferation and differentiation, all of which are vital for achieving predictable and reliable in vivo outcomes. Further, the review seeks to synthesize these advances and their interplays to provide a strategic insight for translating patient-specific, biodegradable Zn implants into clinical practice.

Graphical abstract

Neutral H₂O₂ electrosynthesis via two-electron oxygen reduction reaction (2e⁻-ORR) is a promising alternative to replace traditional anthraquinone processes. However, it still remains significantly challenging to develop efficient electrocatalysts due to sluggish neutral 2e⁻-ORR kinetics. Herein, we reported abundant ultrafine Co/Co₂O₃ nanoparticles (NPs) anchored oxidic nitrogen-doped carbon nanotubes (Co/Co₂O₃@OCNT) derived from the pyrolysis of the mixed OCNT and Co@Tpy, presenting synergistical enhancement effect on the water dissociation to supply active hydrogen coupling with O₂ to produce H₂O₂ at positive onset potential of 0.66 V vs. RHE. As a result, Co/Co₂O₃@OCNT achieves a record current density of 4.0 mA cm⁻² at 0.2 V vs. RHE and nearly 100% H₂O₂ selectivity at the potential from 0 to 0.5 V vs. RHE. In situ observations demonstrated that ultrafine Co/Co₂O₃ NPs and nitrogen-doped carbon supports would synergistically improve the active hydrogen feeding further to facilitate the formation of key intermediate *OOH. Furthermore, based on the sandwiched configuration of the flow cell, Co/Co₂O₃@OCNT shows a superior performance with the yield rate of salt-free aqueous H₂O₂ solution around 63.4 mol g_cat⁻¹ h⁻¹ at 200 mA cm⁻² and the corresponding Faradaic efficiency of 85%. Moreover, integration of Co/Co₂O₃@OCNT into this cell achieves high real-time production concentration of H₂O₂ around 20 mM at 200 mA cm⁻² by varying the pure water flow rate to 1 mL min⁻¹, suggesting the huge potential of salt-free H₂O₂ solution production. This work provides a novel strategy for developing efficient neutral electrocatalysts and feasible process of neutral H₂O₂ production.

Graphical Abstract

Lithium iron phosphate (LFP) batteries, boasting significant advantages in cost-effectiveness, safety, and longevity, are extensively utilized as the core components for electric vehicles. However, with the increasing end-of-life of LFP batteries, the recycling of these spent batteries has become a crucial and urgent matter. Given the relatively short process and high-value-added recycled products, the direct regeneration of cathode materials from spent LFP batteries has become a highly preferred approach. This paper provides a comprehensive review of the research status and technical challenges of direct regeneration technologies (i.e., solid-phase sintering, hydrothermal repair and electrochemical repair technology) applicable to spent LFP cathode materials. The failure mechanisms of LFP, as well as the detailed processes and recent advancements in recycling pretreatment are elaborated and summarized. Additionally, this paper extends to introduce the research advancements in innovative upgrading regeneration of cathode materials. Finally, a comparative analysis of the three direct regeneration strategies is conducted, emphasizing their respective advantages, limitations, and target application fields. It is anticipated to establish a comprehensive reference framework for the efficient regeneration and reuse of cathode materials from spent LFP batteries, thus promoting the green and sustainable development of the new energy vehicle industry.