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Developing highly effective and stable non‐precious bifunctional oxygen electrocatalysts is crucial and challenging. Herein, we report nano‐mediated straight bamboo‐shaped nitrogen‐doped carbon nanotubes modified with encapsulated NiCo2S4‐based nanoparticles (E‐NiCo2S4/SBS‐NCNTs) by electrodeposition and procedural calcination strategy, in which nitrogen‐doped carbon nanotubes with straight bamboo shape (SBS‐NCNTs) show more average diameter and encapsulated NiCo2S4‐based nanoparticles (E‐NiCo2S4) are coated by carbon, and what makes us even more excited is that they are evenly dispersed on SBS‐NCNTs surface, not just at the tip or inside. When applied for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), E‐NiCo2S4/SBS‐NCNTs show excellent catalytic activity, and onset potential (Eonset) in OER and ORR is only 1.52 V and 0.95 V (vs. RHE) in 0.1 M KOH, respectively. More importantly, the hybrids exhibit good methanol tolerance, with almost unchanged for ORR performance after adding 0.5 M methanol, and it has highly stability, the current density dropped by 22% after 7 h of reaction. The interaction of NiCo2S4 with the external carbon layer can greatly enhance the electrocatalytic activity toward the OER and it has a complete 4e– reaction process toward the ORR. The excellent electrocatalytic activity is mainly due to synergistic enhancement effect, in which SBS‐NCNTs with highly catalytic activity provide good conductivity, expose more active sites and promotes fast mass transfer; Carbon‐coated NiCo2S4‐based nanoparticles can improve the local work function of SBS‐NCNT through synergistic electronic interaction, promoting O2 adsorption, ensure rapid electron transport, and enable SBS‐NCNT to improve its electrocatalytic activity. Because of the weakness of Ostwald effect and synergistic enhancement, the stability and catalytic activity of NiCo2S4‐based nanoparticles can be greatly improved. All these advantages can synergistically improve the electrocatalytic efficiency and make it become one of the most promising bifunctional oxygen electrocatalysts. [ABSTRACT FROM AUTHOR]

The highly immunosuppressive tumor microenvironment (TME) restricts the efficient activation of immune responses. To restore the surveillance of the immune system for robust activation, vast efforts are devoted to normalizing the TME. Here, a manganese-doped layered double hydroxide (Mn-LDH) is developed for potent anti-tumor immunity by reversing TME. Mn-LDH is synthesized via a one-step hydrothermal method. In addition to the inherent proton neutralization capacity of LDH, the introduction of manganese oxide endows LDH with an additional ability to produce oxygen. Mn-LDH effectively releases Mn 2+ and Mg 2+ upon exposure to TME with high levels of H + and H 2 O 2 , which activates synthase-stimulator of interferon genes pathway and maintains the cytotoxicity of CD8 + T cells respectively, achieving a cascade-like role in innate and adaptive immunity. The locally administered Mn-LDH facilitated a "hot" network consisting of mature dendritic cells, M1-phenotype macrophages, as well as cytotoxic and helper T cells, significantly inhibiting the growth of primary and distal tumors. Moreover, the photothermal conversion capacity of Mn-LDH sparks more robust therapeutic effects in large established tumor models with a single administration and irradiation. Overall, this study guides the rational design of TME-modulating immunotherapeutics for robust immune activation, providing a clinical candidate for next-generation cancer immunotherapy., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Nanofluidics is an emerging hot field that explores the unusual behaviors of ions/molecules transporting through nanoscale channels, which possesses a broad application prospect. However, in situ probing bioactivity of functional proteins on a single-molecule level by a nanofluidic device has not been reported, and it is still a big challenge in the field. Herein, we reported a biological nanofluidic device with a single-protein sensitivity, based on natural proton-pumping protein, bacteriorhodopsin (bR), and a single SiNx nanopore. Nanofluidic single-molecule probing of bR proton-pumping activity and its light response were achieved under applied voltage of 0 V, by biologically self-powered steady-state ionic current nanopore sensing. Green-light irradiation of the device led to the monitoring of a steady-state proton current of ∼3.51 pA/per bR trimer, corresponding to charge density of 815 μC/cm 2 generated by each bR monomer, which far exceeded the previously reported value of 1.4 μC/cm 2 . This finding and method would promote the development of artificial biological and hybrid nanofluidic devices in biosensing and energy conversion applications.