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Fluorinated carbon (CFx), a thriving member of the carbonaceous derivative, possesses various excellent properties of chemically stable, tunable bandgap, good thermal conductivity and stability, and super-hydrophobic due to its unique structures and polar C-F bonding. Herein, we present a brief review of the recent development of fluorinated carbon materials in terms of structures, properties and preparation techniques. Meanwhile, the applications in energy conversions and storage devices, biomedicines, gas sensors, electronic devices, and microwave absorption devices are also presented. The fluorinated carbon contains various types of C-F bonds including ionic, semi-ionic and covalent C-F, C-F2, C-F3 bonds with tunable F/C ratios. The controllable designing of C-F bonding and F/C ratios play a key role to optimize the properties of fluorinated carbon materials. Until now, the potential issues and future opportunities of fluorinated carbon are proposed. The present review will provide a direction for tuning C-F bonding and F/C ratios, developing a safe and efficient fluorination method and popularizing the applications of fluorinated carbon materials.

Two-dimensional graphene is easy to aggregate and hard to transfer because of the van der Waals forces between graphene layers. The three-dimensional (3D) graphite-like capsules (GCs) disperse well and exhibit robust structural stability and have a potential for promising applications in energy storage, drug delivery, catalyst substrate, etc. Here, we develop a catalytic chemical vapor deposition route for the synthesis of 3D GCs with unprecedented thickness and morphology control. The theoretical results indicate that the strong chemisorption and charge transfer between ZnO and acetylene allow the layer-by-layer formation of GCs that is later confirmed by the experimental data. The 3D GCs are synthesized with thickness control from three atomic layers to ∼300 atomic layers over various oxides with predesigned shapes of microscale tetrapods, nanospheres, nanorods, nanocubes, etc. In particular, the formation mechanism of GCs is investigated using the ZnO surface as a catalyst through systematically experi...

A method is designed to improve the luminescence of AlN-based phosphors by tuning the band structure and crystal structure due to alloying with GaN. The pure (Al,Ga)N:Eu phosphors were initially prepared by gas-phase reaction in an NH3 atmosphere. GaN alloying was used to expand the crystal lattice of AlN due to Ga3+ substituting for smaller Al3+ ions, making dissolution of Eu2+ easier. The dissolution of Ga in the AlN lattice was proven by the result of the Rietveld refinement and the increase in lattice parameters with increasing Ga content. To introduce other energy states mixing with the 5d states of Eu2+, Ga doping was also used to tune the band structure of AlN by acting on Eu2+ ions. The theoretical result was analyzed using the Cambridge Sequential Total Energy Package (CASTEP). According to the calculated total and atom resolved partial density of states, it was observed that the Ga 5p states contribute a large portion to the corresponding Eu2+ absorption band in (Al,Ga)N:Eu phosphors. As a consequence, an enhanced emission intensity at 470 nm and a high quantum efficiency for excitation at 330 nm was obtained despite of stronger thermal quenching of the (Al,Ga)N:Eu phosphors compared with AlN:Eu.

Cu nanocrystals are applied extensively in several fields, particularly in the microelectron, sensor, and catalysis. The catalytic behavior of Cu nanocrystals depends mainly on the structure and particle size. In this work, formation of high-purity Cu nanocrystals is studied using a common chemical vapor deposition precursor of cupric tartrate. This process is investigated through a combined experimental and computational approach. The decomposition kinetics is researched via differential scanning calorimetry and thermogravimetric analysis using Flynn-Wall-Ozawa, Kissinger, and Starink methods. The growth was found to be influenced by the factors of reaction temperature, protective gas, and time. And microstructural and thermal characterizations were performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry. Decomposition of cupric tartrate at different temperatures was simulated by density functional theory calculations under the generalized gradient approximation. High crystalline Cu nanocrystals without floccules were obtained from thermal decomposition of cupric tartrate at 271°C for 8 h under Ar. This general approach paves a way to controllable synthesis of Cu nanocrystals with high purity.

The facile preparation of ZnO possessing high visible luminescence intensity remains challenging due to an unclear luminescence mechanism. Here, two basic approaches are proposed to enhance the luminescent intensity based on the theoretical analysis over surface defects. Based on the deduction, we introduce a methodology for obtaining hybrid tetrapod-like zinc oxide (T-ZnO), decorated by carbon nanomarterials on T-ZnO surfaces through the catalytic chemical vapor deposition approach. The intensity of the T-ZnO green emission can be modulated by topography and the proportion of carbon. Under proper experiment conditions, the carbon decorating leads to dramatically enhanced luminescence intensity of T-ZnO from 400 to 700 nm compared with no carbon decorated, which elevates this approach to a simple and effective method for the betterment of fluorescent materials in practical applications.