In this paper, a non‐noble catalyst was prepared by a simple homogeneous precipitation method and could be applied for 5‐hydroxymethylfurfural (HMF) hydrodeoxygenation (HDO) to 2, 5‐dimethylfuran (DMF). The catalyst was characterized by SEM, TEM, XRD, FT‐IR, BET, XPS, ICP and H2‐TPR. The cobalt species in the catalysts dispersed on the surface of boron nitride (BN) evenly. There is a strong interaction between BN and cobalt species in the Co/BN catalysts with vast B−O defects. Under the optimal conditions, HMF can be completely converted and the selectivity of Co/BN catalyst for DMF can reach as high as 91.67 %. It is crucial that the stability of the catalyst was maintained after five cycles by simple centrifugation. Due to its simple preparation process, low cost and high selectivity, the catalyst will be applied widely in the area of industrial catalysis.

Quantum dots have received great interest due to their excellent optoelectronic properties. However, the surface defects of quantum dots affect the carrier transport and ultimately reduce the photovoltaic efficiency. In this paper, a core-shell quantum dot by hot-injection method is prepared to grow a narrow-band semiconductor layer (CuInSe 2 (CISe) quantumdot) on the surface of a broad-band core material (cadmium sulfide (CdS) nanocrystal). The composition, structure, optical properties, and decay lifetime of CdS/CISe core-shells are investigated in more detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence (PL), UV-vis spectrophotometry, and fluorescence spectroscopy. The CdS/CISe core-shell structure has a broadened absorption range and still shows CISe-related quantum effects. The increased size of the core-shell and the smaller specific surface area of the CISe shell layer lead to a lower carrier complexation chance, which improves the carrier lifetime.

Quantum dots of I–III–VI ternary compounds exhibit unusual photophysical properties and technological utility, which attract attention and have been intensely investigated. CuInSe2 quantum dots are an environmentally friendly composition, a direct transition, and an adjustable bandgap. Here, we discuss the influence of the Cu/In molar ratio of CuInSe2 quantum dots on Cu-related defects and photo-physical properties, and CuInSe2 quantum dots are synthesized by a green, safe, and low-temperature method in triethylene glycol. The proportion of the +1 and +2 oxidation states of Cu in the quantum dots will change with the Cu/In molar atomic ratio. The +1-oxidation state of Cu will prolong the carrier recombination lifetime and provide favorable conditions for the transfer and collection of carriers. By adjusting for different defect types, we can better apply CISe quantum dots in devices and other fields.

Low-capacity anode materials have been limiting the further take-off of lithium-ion batteries (LIBs), and many researchers are relentlessly pursuing breakthroughs in high-capacity anode materials. Therefore, the properties of materials with a high theoretical capacity and the reasons behind them are worthy of further study. Here, based on the first-principles calculation, we systematically investigate the electrochemical properties of the six flat boron sheets with different hexagonal hole densities η (η = 1/4, 1/5, 1/6, 1/7, 1/8, 1/9), including adsorption, diffusion, theoretical capacity, and open-circuit voltage. We find that due to their own structural and electronic properties, the Li atoms tend to be adsorbed on their hexagonal hole sites, which result in the formation of structures of flat boron sheets with more hexagonal holes that have a higher theoretical capacity for lithium. Besides, their theoretical capacities can be calculated using the empirical equation, with the hexagonal hole densities (η). Finally, we obtain their capacities with increasing hexagonal hole density (η), which are 620, 708, 826, 992, 1240, and 1653 mA h g −1 , respectively. Therefore, our results indicate that the porous structure of the anode material is beneficial to improve the storage capacity performance of LIBs.

Silicon-on-insulator (SOI) devices have many advantages, such as high speed, low energy consumption, radiation-hard, and high integration. In this paper, the separation by implanted oxygen process under low-dose implantation conditions is studied by the two-step implantation method combined with the internal thermal oxidation process. The effects of different types of silicon wafers and different implantation doses on SOI surface defects, top Si thickness, buried oxide (BOX) layer thickness, BOX layer breakdown voltage, and top Si defect density were investigated. Ultra-thin SOI wafers are prepared by epitaxial silicon wafers and control the first implantation dose. The number of surface defects of SOI materials is less than 100 counts, the breakdown voltage of the BOX layer is about 7.8 MV/cm, and the top Si dislocation density is about 8 × 103 cm−2.