Jinyuan Zhou

Humidity interference remains one of the most critical challenges hindering the practical applications of metal oxide semiconductor based hydrogen (H2) sensors. Although mesoporous silica molecular sieves have been widely used as protective diffusion layers to alleviate the adverse effect of humidity, maintaining long-term sensing performance under highly humid conditions is still challenging. Herein, we report a strategy of confining ultrasmall CeO2 particles within the channels of mesoporous silica molecular sieve (CeO2-SBA-15) materials to enhance the humidity tolerance of electrospinning terbium-doped tin dioxide nanofiber-based (Tb-SnO2)-based H2 sensors. In this design, the synergistic effect of gas enrichment within the mesoporous SBA-15 diffusion layer and the superior catalytic activity of channel-confined CeO2 substantially enhances the sensor's H2 response. More importantly, the confined CeO2 introduces abundant reversible redox sites through the Ce3⁺/Ce4⁺ pairs, thereby promoting oxygen activation, facilitating surface reaction kinetics, and mitigating humidity-induced performance degradation. As a result, the optimized Tb-SnO2/5% CeO2-SBA-15 sensor delivers a high response of 69.23 toward 10 ppm H2 at 280℃, an ultralow detection limit of 20 ppb, excellent linearity over a wide concentration range, rapid response/recovery, and outstanding selectivity. Notably, the sensor retains over 85% of its initial response even at 85% RH, much higher than that for the Tb-SnO2/SBA-15 one (51%). This work provides a versatile strategy for integrating catalytically active species into functional porous molecular sieves, offering new insights into the development of high-performance and humidity-tolerant gas sensors for H2 and other target gases.

Fiber-shaped aqueous zinc-ion batteries (FAZIBs) emerge as a promising energy storage device for future wearable electronics. Vanadium-based oxides possess high theoretical capacity, benefiting from their multiple oxidation states and versatile open-framework structures, yet its practical application is largely hindered by the poor electrical conductivity and cycling instability. Herein, we develop a core–sheath fiber as a cathode for FAZIBs via coaxial wet-spinning. The incorporation of reduced graphene oxide (rGO) significantly enhances electron transport in the V2O3 core, while the utilization of holey rGO (HrGO) as a sheath guarantees rapid ion diffusion at the same time renders further mechanical and electrical supports. The obtained V2O3/rGO@HrGO fiber exhibits a high volumetric capacity of 429 mAh cm−3 at 0.4 A cm−3 and still retains 275 mAh cm−3 at 4.0 A cm−3 with improved stability. This study provides an alternative option for the design of a high performance fiber cathode for future wearable aqueous ZIBs.

Luminescence platinum(II) complexes have demonstrated significant potential as highly efficient theranostic probes that integrate bioimaging and chemotherapeutic capabilities. The construction of platinum(II) complexes-based supramolecular nanoprobes that are capable of both deep-penetrating NIR bioimaging (>800 nm) and tumor chemotherapy is a highly attractive but significantly challenging task. In this study, a series of polymer micelles exhibiting enhanced NIR phosphorescence emission were prepared via electrostatic self-assembly between cationic platinum(II) complexes with anionic poly(acrylate sodium) blocks in water. The platinum(II) complexes in the micellar cores exhibited high aggregation tendency in aqueous solution, which is driven by Pt(II)···Pt(II) and π–π stacking interactions and further promoted by the electrostatic interactions. Consequently, the platinum(II)-containing polymer micelles E₁₃₆A₂₈-1e and E₁₃₆A₂₈-3 showed intense NIR emission bands at 836 and 898 nm with high quantum yields and large Stokes shifts, respectively. Benefiting from their superior NIR phosphorescence and anticancer activity in vitro, E₁₃₆A₂₈-1e and E₁₃₆A₂₈-3 displayed excellent NIR imaging of tumor tissues in vivo, permitting the visualization of drug accumulation in tumor areas and the in situ killing of cancer cells without harming healthy organs. This work provides an extraordinary opportunity to create Pt-based nanomedicines with NIR luminescence applied for cancer theranostics.

Developing efficient and stable nonprecious metal bifunctional electrocatalysts remains one of the key challenges in achieving low-cost water splitting for hydrogen production. Cobalt molybdate (CoMoO₄) has attracted considerable attention due to its promising catalytic activity; however, its inherent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance still require significant improvement. Elemental doping is a widely used strategy to regulate the electronic structure and surface properties of catalysts. Nevertheless, the structural evolution of N/P-doped CoMoO₄-based catalysts during the HER and OER processes, as well as the underlying mechanisms linking this evolution to catalytic performance, remain unclear. This work aims to elucidate the effects of nitrogen (N) and phosphorus (P) codoping on the HER and OER activities of CoMoO₄ catalysts and to investigate their dynamic reconstruction mechanisms under electrocatalytic conditions. Electrochemical testing indicates that NP_CoMoO₄ exhibits optimal performance in the HER, featuring the lowest overpotential (161 mV at 10 mA cm^-2), the lowest charge-transfer resistance, and excellent stability. Phosphorus doping significantly enhances oxygen evolution activity, with P_CoMoO₄ demonstrating an overpotential of only 377 mV at 100 mA cm^-2. Density functional theory calculations confirm that codoping with N and P eliminates the band gap near the Fermi level in CoMoO₄, thereby enhancing electron conduction and HER activity. Conversely, P doping improves conductivity while maintaining structural stability, which benefits the OER. Overall, this study elucidates the mechanism by which nonmetallic doping regulates the restructuring behavior and catalytic performance of CoMoO₄, offering a novel strategy for designing highly efficient bifunctional electrocatalysts for water splitting.

Exploring efficient, low-cost, and pH-versatile electrocatalysts for hydrogen precipitation is vital for the development of practical hydrogen production via water electrolysis. However, most existing electrocatalysts suffer from limitations such as high overpotentials, a reliance on expensive noble metals, or poor stability under extreme pH conditions, hindering their practical application. Among the many electrocatalytic materials, transition metal phosphides (TMPs) are considered a promising class of hydrogen evolution reaction (HER) catalytic materials due to their abundant reserves and tunable electronic structures. Despite the demonstrated potential of TMPs in electrolytic water-to-hydrogen reactions in recent years, there are still several issues that must be addressed, including the insufficient exposure of active sites, high charge-transfer barriers under full pH conditions, and poor long-term stability. In this work, B and Ce codoped CoP/NiCoP heterostructured nanoarrays were grown on nickel foam. This codoped catalyst exhibits a larger electrochemically active surface area, which significantly improves its HER kinetics and charge-transfer ability. The B, Ce codoped CoP/NiCoP catalyst presents good catalytic performance over a wide pH range: at a current density of 10 mA cm^-2, overpotentials of 89, 123, and 44 mV are achieved under acidic (0.5 M H₂SO₄), neutral (1 M PBS), and alkaline (1 M KOH) conditions, respectively. Moreover, the catalyst exhibits Tafel slopes of only 55 mV dec^-1 (0.5 M H₂SO₄), 105 mV dec^-1 (1 M PBS), and 51 mV dec^-1 (1 M KOH). After 20 h of stability testing at a current density of 100 mA cm^-2, current density retention rates of 85, 60, and 92% are achieved under acidic, neutral, and alkaline conditions, respectively. This study provides new insights into the implementation of a cation-anion codoping strategy for the design and preparation of low-cost, high-efficiency electrocatalysts.

Sluggish reaction kinetics and severe dendrite growth are two main obstacles that hinder lithium-sulfur batteries (LSBs) from practical applications. Here, unconventionally d-p hybridized ferromagnetic Fe₃M (M = Al, Si, Ga, Ge, Sn) materials are studied as the electrocatalysts and conductive scaffolds for LSBs. This reveals that under a magnetic field, the d-p hybridization can be obviously enhanced via the electron cloud overlap between M and Fe atoms around the Fermi level, thereby leading to highly improved kinetics of the entire Li-S reactions. Furthermore, the magnetic field and magnetized Fe₃M can locally regulate the diffusion pathways of Li⁺ through the Lorentz force, facilitating uniform lithium deposition. With Fe₃Ga as the optimal option, under a magnetic field of 280 mT, the Fe₃Ga@CNF/S cathode delivers specific capacities of 1343.3 and 1091.7 mA h g^-1, respectively, at 0.1C and 3.0C, along with an ultralow capacity decay rate of only 0.0065% for 300 cycles at 10.0C, while the Fe₃Ga@CNF/Li anode maintains a low overpotential of 24.5 mV over 100 days of cycling at 5 mA cm^-2. Consequently, the performances of the Li-S full cell with the Fe₃Ga@CNF/S cathode and the Fe₃Ga@CNF/Li anode are significantly improved, producing a capacity of 1027.1 mA h g^-1 at 0.2C and 657.5 mA h g^-1 at 3.0C, and a Li-S pouch cell with a sulfur loading of 0.146 g delivers a high specific energy density of 317 Wh kg^-1 when tested under the magnetic field.

Polymer incorporation has been proven effective to enhance the mechanical strength of MXene fibers via interfacial cross-linking, yet the simultaneous improvement in electrochemical performance, particularly output capacitance and high rate capability, remains a challenge, and the major obstacle is identified as the sluggish ion diffusion kinetics. Herein, interlayer manipulation in Ti₃C₂T_X fiber is proposed, and the roles of substitutional groups in celluloses are examined. The addition of cellulose can obviously improve the spinnability of MXene dope and effectively bridge the adjacent Ti₃C₂T_X nanosheets via hydrogen bonds. Moreover, hydroxyethyl cellulose with a suitable group size and moderate adsorption ability is preferred for diminishing the steric effect and facilitating rapid proton transport. Simultaneous improvements in capacitance (1531 F cm^-3 at 2 A cm^-3) and strength (∼76 MPa) are achieved for the optimized M-HEC-1.0% fiber together with a superior high rate capability retaining 89.2% at 15 A cm^-3.