HfCN nanoparticles were synthesized using the urea-glass route, employing hafnium chloride, urea, and methanol as raw materials. The synthesis process, polymer-to-ceramic conversion, microstructure, and phase evolution of HfCN/C nanoparticles were thoroughly investigated across a wide range of molar ratios between the nitrogen source and the hafnium source. Upon annealing at 1600 °C, all precursors demonstrated remarkable translatability to HfCN ceramics.
View Article and Find Full Text PDFThe slow kinetics and poor structural stability prevent transition metal selenides from being widely used in sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). Herein, the "flower-like" porous carbon anchored by Zn-Mn binary selenides (ZMS@FC) composites are fabricated by selenizing the modified hierarchically metal-organic frameworks. The 2D conductive hierarchically flakes' abundant pore structure and multiple active sites shorten the ion diffusion length and promote conductivity, while the synergistic effect of the binary metals and intrinsic large pseudocapacitive contribution effectively improve capacity and rate performance.
View Article and Find Full Text PDFAlthough the spontaneous vapor-solid growth of SiC nanowires is a well-established phenomenon, the exact mechanism by which nanowires grow on substrates is still poorly understood. Here, we studied the initial growth of SiC nanowires on carbon sources with different nanotextures via a catalyst-free vapor reaction between a polyacrylonitrile-based carbon fiber and a silicon powder. The results revealed that the SiC nanowires were preferentially formed on the carbon fiber with a higher degree of graphitization.
View Article and Find Full Text PDFZnSe nitrogen-doped carbon composite nanofibers (ZnSe@N-CNFs) were derived as anode materials from selenization of electrospinning nanofibers. Electron microscopy shows that ZnSe nanoparticles are distributed in electrospinning nanofibers after selenization. Electrochemistry tests were carried out and the results show the one-dimensional carbon composite nanofibers reveal a great structural stability and electrochemistry performance by the enhanced synergistic effect with ZnSe.
View Article and Find Full Text PDFSheng Wu Yi Xue Gong Cheng Xue Za Zhi
October 2006
The preparation of tetracalcium phosphate (Ca4(PO4)2O, TTCP)was studied. Then calcium phosphate cement (CPC) was prepared. The setting time, pH value, compressive strength, X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis of CPC were studied.
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