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The discovery of highly efficient broadband near infrared (NIR) emission material is urgent and crucial for constructing NIR lighting sources and emerging applications. Herein, a series of NIR emission hexafluorides A2BMF6:Cr3+ (A = Na, K, Rb, Cs; B = Li, Na, K, Cs; M = Al, Ga, Sc, In) peaking at ≈733–801 nm with a full width at half maximum (FWHM) of ≈98–115 nm are synthesized by a general ammonium salt assisted synthesis strategy. Benefiting from the pre‐ammoniation of the trivalent metal sources, the Cr3+ can be more efficiently doped into the A2BMF6 and simultaneously prevent the generation of the competitive phase. Particularly, Na3ScF6:Cr3+ (λem = 774 nm, FWHM ≈ 108 nm) with optimal Cr3+‐doping concentration of 35.96% shows a high internal quantum efficiency of 91.5% and an external quantum efficiency of ≈40.82%. A lighting emitting diode (LED) device with a NIR output power of ≈291.05 mW at 100 mA driven current and high photoelectric conversion efficiency of 20.94% is fabricated. The general synthesis strategy opens up new avenues for the exploration of Cr3+‐doped high efficiency phosphors, and the as‐obtained record NIR output power demonstrates for NIR LED lighting sources applications. [ABSTRACT FROM AUTHOR]

Regulating nanocrystal composition with multiphase compounds is considered an efficient approach to enhance electrochemical performance and structure stability. Nevertheless, the thorough understanding of significant reaction mechanisms and insight into the reason of enhanced performance is still urgent. In this work, the bimetallic sulfide Bi2S3/MoS2 heterogeneous with abundant phase boundaries is successfully fabricated. The in situ investigation of Na+‐storage mechanism confirms that enormous phase boundaries are self‐generated by composition optimization and rational structural design. More importantly, the full understanding of abundant phase boundaries on the enhanced electrochemical properties is explicitly unraveled by combining theoretical analysis and experimental results. It confirms that the interior self‐built‐in electric‐field induced by phase boundaries can enhance the reaction kinetics and boost the charge transfer. Besides, the Bi/Na2S interface is well‐maintained by the homogeneously distributed phase boundaries, effectively improving the conversion/alloying reversibility and keeping integrity without agglomeration and pulverization. As expected, the Bi2S3/MoS2 composite exhibits superior rate capability and long‐cycling stability (323.4 mAh g−1 after long‐term 1200 cycles at ultrahigh rate of 10 A g−1). This strategy of constructing sufficient phase boundaries sheds light on the enhancement of reversibility and stability for other advanced conversion/alloying‐type anode materials. [ABSTRACT FROM AUTHOR]

Abstract: A theranostic platform combining synergistic therapy and real‐time imaging attracts enormous attention but still faces great challenges, such as tedious modifications and lack of efficient accumulation in tumor. Here, a novel type of theranostic agent, bismuth sulfide@mesoporous silica (Bi2S3@mPS) core‐shell nanoparticles (NPs), for targeted image‐guided therapy of human epidermal growth factor receptor‐2 (HER‐2) positive breast cancer is developed. To generate such NPs, polyvinylpyrrolidone decorated rod‐like Bi2S3 NPs are chemically encapsulated with a mesoporous silica (mPS) layer and loaded with an anticancer drug, doxorubicin. The resultant NPs are then chemically conjugated with trastuzumab (Tam, a monoclonal antibody targeting HER‐2 overexpressed breast cancer cells) to form Tam‐Bi2S3@mPS NPs. By in vitro and in vivo studies, it is demonstrated that the Tam‐Bi2S3@mPS bear multiple desired features for cancer theranostics, including good biocompatibility and drug loading ability as well as precise and active tumor targeting and accumulation (with a bismuth content in tumor being ≈16 times that of nontargeted group). They can simultaneously serve both as an excellent contrast enhancement probe (due to the presence of strong X‐ray‐attenuating bismuth element) for computed tomography deep tissue tumor imaging and as a therapeutic agent to destruct tumors and prevent metastasis by synergistic photothermal‐chemo therapy. [ABSTRACT FROM AUTHOR]