Among the many potential Eu 2+ -activated sodium superionic conductor (NASICON)-based host materials, the Sc 3+based NASICON phosphor (Na 3 Sc 2 (PO 4 ) 3 :Eu 2+ ) is a promising phosphor material for high-power lighting applications owing to its unusual thermal stability at elevated temperatures. It has previously been shown that negative thermal quenching (TQ) can be tailored to zero TQ depending on the Eu 2+ concentration. However, the obtained zero-TQ composition has low photoluminescent quantum yields, which hinders its applicability to high-power lighting. Herein, we report a holistic study of the tuning of thermal stability from negative TQ to zero TQ while preserving the original emission efficiency by introducing Lu 3+ ions in Na 3 Sc 2 (PO 4 ) 3 :Eu 2+ . Furthermore, we fabricated a high-power white light-emitting diode using optimized Lu 3+ -doped Na 3 Sc 2 (PO 4 ) 3 :Eu 2+ as the blue component, delivering a high color-rendering index value of 90 with a high luminous efficiency value of 25 lm/W obtained at a flux current of 1000 mA. Therefore, the findings of this work provide novel scientific insights into the importance of structure−property relationships in designing highly efficient thermally stable phosphors for high-power lighting applications.

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Despite pioneering as the holy grail in photocatalysts, abundant reports have demonstrated that g-C3N4 performs poor photocatalytic activity due to its high recombination rate of photo-induced charge carriers. Many efforts have been conducted to overcome this limitation in which the semiconductor–semiconductor coupling strategies toward heterojunction formation were considered as the easiest but the most effective method. Herein, a one-pot solid-state reaction of thiourea and sodium molybdate as precursors at different temperatures under N2 gas was applied for preparing composites of MoS2/g-C3N4. The physicochemical characterization of the final products determines the variation in contents of components (MoS2 and g-C3N4) via the increase of synthesis temperature. The enhanced photocatalytic activity of the MoS2/g-C3N4 composites was evaluated by the degradation of Rhodamine B in an aqueous solution under visible light. Therein, composites synthesized at 500 °C showed the best photocatalytic performance with a degradation efficiency of 90%, much higher than that of single g-C3N4. The significant improvement in photocatalytic performance is attributed to the enhancement in light-harvesting and extension in photo-induced charge carriers’ lifetime of composites which are originated from the synergic effect between the components. Besides, the photocatalytic mechanism is demonstrated to well-fit into the S-scheme pathway with apparent evidences.

The investigation into the use of earth-abundant elements as electrode materials for lithium-ion batteries (LIBs) is becoming more urgent because of the high demand for electric vehicles and portable devices. Herein, a new green synthesis strategy, based on a facile solid-state reaction with the assistance of water droplets' vapor, was conducted to prepare Fe 2 (MoO 4 ) 3 nanosheets as anode materials for LIBs. The obtained sample possesses a two-dimensional stacked nanosheet construction with open gaps providing a much higher surface area compared to the bulk sample conventionally synthesized. The nanosheet sample delivers an ultrahigh reversible capacity (1983.6 mA h g −1 ) at a current density of 100 mA g −1 after 400 cycles, which could be related to the contribution of pseudocapacitance. The enhancement in cyclability and rated performance with an interesting increased capacity could be caused by the effect of electrochemical milling and the in situ formation of metallic particles in its lithium-ion storage mechanism.

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A simple synthesis procedure for solid-state reactions at an intermediate temperature ( 500°C) is applied to synthesize F-doped spinel-layered 0.5Li 2 MnO 3 •0.5Li 4 Mn 5 O 12 (Li 3 Mn 3 O 7.5-x F x with x = 0, 0.05, 0.1, and 0.2). The F-doping does not affect the crystal structure or the morphology of the pristine sample. However, F-doping increases the Mn 3+ content, leading to an improved electronic conductivity and a lower charge-transfer resistance. In addition, F-doping also reduces the difference of voltage between the oxidation and reduction processes, and enhances the Li + diffusion coefficient (with a maximum four times higher than that of the pristine sample). Consequently, the capacity and rate capability of the cathode are improved by F-doping (the x = 0.1 sample can provide a high capacity of 300 mAh g −1 at C/10).