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High-efficiency quantum cutting materials have great application prospects in improving the photoelectric conversion efficiency of silicon-based photoelectric devices. Herein, La3+ and Yb3+ ions co-doped CsPbCl 3 perovskite quantum dots (PQDs) were prepared successfully via the modified hot-injection method. La3+ and Yb3+ ions codoping makes the PLQY of CsPbCl 3 PQDs increase from 5% to 168%. This is because Yb3+ ions doping makes the effective quantum cutting process happen, as well as La3+ ions doping effectively reduces non-radiative transition in CsPbCl 3 PQDs and further improves the quantum cutting efficiency. Finally, La3+ and Yb3+ ions co-doped CsPbCl 3 PQDs film were integrated on silicon-based photodetectors. The spectral range of silicon-based photodetectors is extended to the ultraviolet (UV) region (200–400 nm) besides the visible spectral region. The external quantum efficiency (EQE) is around 67%, and the responsivity is 0.14 A/W, which is comparable to the highest value previously reported. This work provides a new strategy to improve the quantum cutting efficiency and the performance of silicon-based photodetectors. • The PLQY of CsPbCl 3 PQDs increase from 5% to 168% via La3+ and Yb3+ codoping. • La3+/Yb3+ co-doped CsPbCl 3 PQDs were integrated on silicon photodetectors. • The response spanning of silicon photodetectors is extended to the ultraviolet. [ABSTRACT FROM AUTHOR]

Lead-free halide double perovskites are widely used for phosphors converted light emitting diode (pc-LED) devices. However, it remains a challenge to modulate their spectra to meet different application requirements. Herein, Cs 2 NaInCl 6 :Sb3+ double perovskite crystals with excellent blue emission of self-trapped excitons (STEs) were prepared and a lanthanide ions (Ln3+) doping strategy was employed to enable multicolor emissions in this system. The emission colors can be continuously adjusted in a wide range by altering the Ln3+ ions doping levels. Especially, white light emissions with tunable correlated color temperature were obtained in Tb3+, Ho3+ ions codoped samples. Outstanding photoluminescence quantum yields of the samples are ascribed to the sensitization effect of Sb3+ ions and the efficient energy-transfer from STEs to Ln3+ ions. LED devices were further fabricated to demonstrate the great application potentials of the prepared phosphors. These findings provide deep insights for the designing of multicolor double perovskite phosphors. • Sb3+ and different Ln3+ ions were successfully doped in Cs 2 NaInCl 6 by a hydrothermal method. • The emission colors can be continuously adjusted in a wide range by altering the Ln3+ ions doping levels. • Multi-color light-emitting diodes were designed with single component Cs 2 NaInCl 6 phosphors. [ABSTRACT FROM AUTHOR]

This work aimed at investigating the superiorities of multilayer graphene (MLG) and β-Si 3 N 4 whisker (β-Si 3 N 4w) in synergistically enhancing the toughness of Si 3 N 4 ceramic composites. First, Si 3 N 4 ceramic composites with hybrid 1 wt% MLG and 0 – 5 wt% β-Si 3 N 4w were sintered by spark plasma sintering. Phase constitutions and microstructures of Si 3 N 4 -based ceramic composites were characterized by X-rays diffraction, Raman spectra, and scanning electron microscope. Then, the optimal β-Si 3 N 4w content and sintering process of MLG/β-Si 3 N 4w -toughened Si 3 N 4 ceramic composites were comprehensively optimized by orthogonal experiments. Results indicated that in the case of maintaining the hardness of 15.87 – 18.84 GPa, the fracture toughness of Si 3 N 4 ceramic composites incorporated with 1 wt% MLG and 3 wt% β-Si 3 N 4w was advanced to 11.04 MPa·m1/2, which was 11.29% and 87.12% higher than that of 1 wt% MLG- and 3 wt% β-Si 3 N 4w -reinforced Si 3 N 4 ceramic composites, respectively. Orthogonal experiments demonstrated that 1 wt% MLG/3 wt% β-Si 3 N 4w -toughened Si 3 N 4 ceramic composites sintered at 1600 ℃, 40 MPa, and holding time for 6 min had optimum comprehensive mechanical properties. MLG wrapping and the synergistic effects of pull out, crack deflection, crack branching, and bridging resulted by MLG and β-Si 3 N 4w were the main responsible for the enhancement of toughness. [Display omitted] • MLG/β-Si 3 N 4w synergistic toughened Si 3 N 4 ceramics were sintered by SPS. • Fracture toughness of Si 3 N 4 -based ceramics was enhanced to 11.04 MPa·m1/2. • Optimal contents of MLG and β-Si 3 N 4w were 1 wt% and 3 wt%. • Optimum sintering process were 1600 ℃, 40 MPa, and holding time for 6 min. [ABSTRACT FROM AUTHOR]