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Ammonia borane (AB) hydrolysis is a sustainable and efficient method for hydrogen energy conversion and transportation. Designing a non-precious AB hydrolysis catalyst with high catalytic activity is considered to be promising but challenging. Herein, highly dispersed Cu0.9Ni0.1 alloy nanoparticles (NPs) were successfully fabricated via a conventional wet-chemical co-reduction method on transition metal carbides (Ti3C2Tx), facilitating hydrogen evolution during AB hydrolysis. The optimized Cu0.9Ni0.1/Ti3C2Tx catalyst exhibits an impressive turnover frequency (TOF) of 2429 h−1 at 323 K for AB hydrolysis, with 100% hydrogen selectivity, outperforming those of most non-precious metal catalysts. This enhanced performance is attributed to the synergistic effect between Cu and Ni, as well as the strong electronic metal–support interaction between Ti3C2Tx and Cu0.9Ni0.1 NPs. This study provides a general and simple method for synthesizing highly efficient non-precious metal AB hydrolysis catalysts. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) thin film has highlighted its potential in the photoelectric detection field due to its wide-spectrum and high-absorption capacity. However, the fabrication of controllable and highly quality BP film in large dimensions remains a huge challenge. Herein, we creatively fabricated a centimeter-size highly crystalline BP thin film on the bare silicon substrate using a space-confined chemical vapor transport technique, and we in situ constructed a self-driven BP-based metal–semiconductor–metal photodetector. The as-constructed photodetector achieves a high responsivity of up to 500 mA/W, an external quantum efficiency of 42.1%, a maximum specific detectivity of 3.82 × 1010 cm Hz1/2 W−1, and a small noise-equivalent-power of 3.97 × 10−15 W Hz−1/2 under zero bias voltage at 1550 nm illumination. This work provides a strategy to effectively prepare BP thin film for in situ manufacturing self-driven photodetector, which marks a significant step forward in the integration of BP into the industrial settings. [ABSTRACT FROM AUTHOR]

PbS films grown on quartz substrates by the chemical bath deposition method were annealed in an O2 atmosphere to investigate the role of oxygen in the sensitization process at different annealing temperatures. The average grain size of the PbS films gradually increased as the annealing temperature increased from 400 °C to 700 °C. At an annealing temperature of 650 °C, the photoresponsivity and detectivity reached 1.67 A W−1 and 1.22 × 1010 cm Hz1/2 W−1, respectively. The role of oxides in the sensitization process was analyzed in combination with X-ray diffraction and scanning electron microscopy results, and a three-dimensional network model of the sensitization mechanism of PbS films was proposed. During the annealing process, O functioned as a p-type impurity, forming p+-type PbS layers with high hole concentrations on the surface and between the PbS grains. As annealing proceeds, the p+-type PbS layers at the grain boundaries interconnect to form a three-dimensional network structure of hole transport channels, while the unoxidized p-type PbS layers act as electron transport channels. Under bias, photogenerated electron–hole pairs were efficiently separated by the formed p+-p charge separation junction, thereby reducing electron–hole recombination and facilitating a higher infrared response. [ABSTRACT FROM AUTHOR]

The performance improvements of AlGaN‐based deep ultraviolet light‐emitting diodes (DUV‐LEDs) with multigradient electron blocking layer (EBL) and triangular last quantum barrier (LQB) are investigated. The results show that the maximum internal quantum efficiency (IQE) is improved by 44.9% and light output power (LOP) is improved by 58.1% at 200 A cm−2, exhibiting a tremendous improvement compared to the conventional structure. These improvements are mainly attributed to the fact that both multigradient EBL and triangular LQB can generate negative polarization charges in the graded composition layer, which leads to a significant increase in hole concentration compared to the conventional EBL and LQB structures. Meanwhile, the multigradient EBL can transform the conventional triangular barrier into an arc‐shaped barrier, increasing the electron potential barrier height and decreasing the hole potential barrier height. This unique design suppresses electron leakage and enhances hole injection, leading to a significant enhancement of the IQE and alleviation of the efficiency droop. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP), a two-dimensional (2D) van der Waals (vdW)-layered nanomaterial, has attracted explosive study due to the rediscovery of its 2D counterparts (phosphorene) in 2014. Because of its unique structures, superior electrical and optoelectronic capabilities, and compatibility with silicon-based technologies, it is considered a viable material for high-performance photodetection. Controlled ways for the scalable synthesis of good quality large-sized BP are sought to achieve these wonderful expectations, but perfect methodologies are currently lacking. Meanwhile, cutting-edge research shows that the instability of BP under ambient conditions poses a substantial difficulty in a variety of applications. Here, not only an extensive overview of preparation methods but also a summary of the passivation strategy, photoelectric application, and challenges of BP are provided. [ABSTRACT FROM AUTHOR]

Phosphorene nanoribbons (PNRs) combine the flexibility of one-dimensional (1D) nanomaterials with the large specific surface area and the edge and electron confinement effects of two-dimensional (2D) nanomaterials. In spite of the substantial advances in bulk black phosphorus (BP) manufacturing, achieving PNRs without degradation is still a big challenge. In this work, we present a strategy for the space-confined chemical vapor transport synthesis of quasi-one-dimensional surface-passivated monocrystalline PNRs on a silicon substrate. The growth mechanism of the PNRs is proposed by combining experimental results and DFT calculations, indicating that the P4 molecules can break, restructure, and epitaxially nucleate on the surface of the Au3SnP7 catalyst, and finally prefer to grow along the zigzag (ZZ) direction to form PNRs. The low gas flow rate and an appropriate phosphorus molecule concentration allow the growth of PNRs with structural integrity, which can be regulated by the amount of red phosphorus and the confined space. [ABSTRACT FROM AUTHOR]