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The azobenzene moiety is an intriguing structure that deforms under UV and visible light, indicating a high potential for biomedical applications. However, its reaction to UV radiation is problematic because of its high energy and low tissue penetration. Unlike previous research on azobenzene structures in photoresponsive materials, this study presents a novel method for imparting photostimulation-responsive properties to liposomes by incorporating the azobenzene moiety and extending the light wavelength with up-conversion nanoparticles. First, the azobenzene structure was incorporated into a phospholipid molecule to create Azo-PSG, which could spontaneously form vesicle assemblies in aqueous solutions and isomerizes within 1 h of light exposure. Furthermore, orthogonal up-conversion nanoparticles with a core–shell structure were created by sequentially growing lanthanide rare earths in the shell layer, which efficiently converts near-infrared light into ultraviolet (400 nm) and blue-green (540 nm) light. Combining these core–shell structured up-conversion nanomaterials with Azo-PSG molecules resulted in the creation of a near-infrared light-responsive smart nanoliposome system. Under near-infrared light irradiation, UCNPs emit UV and blue-green light, causing conformational changes in Azo-PSG molecules that allow drug release within 6 h. The reversible structural shift of Azo-PSG in response to light stimulation holds enormous promise for improving drug release techniques. This novel technique also expands the usage of UV-responsive compounds beyond their constraints of low penetration and high biotoxicity, allowing for rapid medication release under NIR light.

Polyoxometalates (POMs) have emerged as potential anode materials for lithium-ion batteries (LIBs) owing to their ability to transfer multiple electrons. Although POM anode materials exhibit notable results in LIBs, their energy-storage mechanisms have not been well-investigated. Here, we utilize various in operandoand ex situtechniques to verify the charge-storage mechanisms of a Keplerate-type POM Na2K23{[(MoVI)MoVI5O21(H2O)3(KSO4)]12[(VIVO)30(H2O)20(SO4)0.5]}·ca200H2O ({Mo72V30}) anode in LIBs. The {Mo72V30}anode provides a high reversible capacity of up to ∼1300 mA h g–1without capacity fading for up to 100 cycles. The lithium-ion storage mechanism was studied systematically through in operandosynchrotron X-ray absorption near-edge structure, ex situX-ray diffraction, ex situextended X-ray absorption fine structure, ex situtransmission electron microscopy, in operandosynchrotron transmission X-ray microscopy, and in operandoRaman spectroscopy. Based on the abovementioned results, we propose that the open hollow-ball structure of the {Mo72V30}molecular cluster serves as an electron/ion sponge that can store a large number of lithium ions and electrons reversibly via multiple and reversible redox reactions (Mo6+↔ Mo1+and V5+/V4+↔ V1+) with fast lithium diffusion kinetics (DLi+: 10–9–10–10cm2s–1). No obvious volumetric expansion of the microsized {Mo72V30}particle is observed during the lithiation/delithiation process, which leads to high cycling stability. This study provides comprehensive analytical methods for understanding the lithium-ion storage mechanism of such complicated POMs, which is important for further studies of POM electrodes in energy-storage applications.

Narrow-band Mn4+-doped fluoride phosphors have become a research hotspot worldwide. In this study, we propose integrated surface modification processes to enhance the performance and stability of the luminescence properties of K2TiF6:Mn4+(KTF) phosphor. These integrated process are applied in the initial synthesis step, coating of the as-synthesized powder post-treatment process, and during the application of the phosphor in the white-light-emitting diode (WLED) device. Surface etching is conducted to remove impurities and small particles in KTF. Double-shell coating forms a stable protective layer outside the KTF. Atomic layer deposition is employed for the surface of the WLED device.

Mn-based layered oxides have been considered the most promising cathode candidates for cost-effective potassium-ion batteries (PIBs). Herein, equiatomic constituents of Ni, Fe, Mg, and Ti have been introduced into the transition metal layers of Mn-based layered oxide to design a high-entropy K0.6Ni0.05Fe0.05Mg0.05Ti0.05Mn0.0725O2(HE-KMO, S= 1.17R). Consequently, the experimental results manifest that the layered structure of HE-KMO is more stable than conventional low-entropy K0.6MnO2(LE-KMO, S= 0.66R) during successive cycling and even upon exposure to moisture. Diffraction and electrochemical measurements reveal that HE-KMO undergoes a solid-solution mechanism, contrary to the multistage phase transition processes typically exemplified in K0.6MnO2. Benefiting from the stabilized high-entropy layered framework and the solid-solution K+storage mechanism, the entropy-stabilized HE-KMO not only demonstrates exceptional rate capability but also shows excellent cyclic stability. Notably, a capacity retention ratio of 86% after 3000 cycles can still be sustained at a remarkable current density of 5000 mA g–1.

Dealing with the water molecule on the surface of LiNi0.6Co0.2Mn0.2O2(NCM) cathode and hydrogen fluoride in the electrolyte is one of the most difficult challenges in Li-ion battery research. In this paper, the surface polymerization of tetraethyl orthosilicate (TEOS) on NCM to generate ethoxy-functional polysiloxane (EPS) wrapped NCM (E-NCM) cathode under mild conditions and without any additions is utilized to solve this intractable problem. The differential scanning calorimetry, transmission electron microscopy, and X-ray photoelectron spectroscopy results show that the formed amorphous coating can provide a protective shell to improve the NCM thermal stability, suppress the thickening of the solid electrolyte interphase (SEI) layer, and scavenge HF in the electrolyte. The E-NCM composite with 2 mol % EPS delivers a high discharge capacity retention of 84.9% after 100 cycles at a 1 C discharge rate in the 2.8–4.3 V potential range at 55 °C. Moreover, electrochemical impedance spectroscopy measurements reveal that the EPS coating could alleviate the impedance rise during cycling especially at an elevated temperature. Therefore, the fabricated E-NCM cathode with long-term cycling and thermal stability is a promising candidate for use in a high-energy Li-ion battery.