Advanced Materials Research Vol. 893

Abstract: In this paper, the W-Al2O3 solar energy selective absorbing coating was prepared by magnetron sputtering. The selective absorption coating layers were obtained by setting different tungsten target sputtering power and sputtering time. The process parameters of magnetron sputtering were presented by comparing the selective absorption coating layers absorptivity and reflectivity.

Abstract: The solar selective absorbing coating is the key component of solar energy collector which determines the heat conversion efficiency. The coating materials mentioned in this paper were prepared by Al as substrate, Al₂O₃-Pt as absorbing layer and metal Ag as infrared reflector. We got three kinds of coatings by adjusting the magnetron sputtering process. Respectively testing and analyzing the performance and microstructure showed that element content of Al, N, O in the coating are of important influence on its performance, meanwhile, the better the crystallization of coatings surface, the more helpful to improve the performance of its corrosion resistance and its moisture and heat resistance.

Abstract: LiFePO₄/C materials were synthesized by spray-drying method. The particle size of the LiFePO₄/C was controlled by mechanical crushing or airflow crushing. The morphology, structure and electrochemical properties of the materials were characterized. The results show that: The smaller powder particle and better particle size distribution could be got using the two granularity control methods above. The special surface area of the material increased, the tap density decreased and the high rate performance deteriorated when the particle size of LiFePO₄/C was controlled. After the particle size of LiFePO₄/C is controlled the contacts of LiFePO₄/C and carbon will deteriorate. The special capacity of the material decreases and the rate performance deteriorates, due to the stripping of carbon.

Abstract: Classical molecular dynamic simulation was performed on electrolyte system of lithium-montmorillonite/poly(ethylene oxide) to investigate mobility behavior of lithium once it had been absorbed into montmorillonites octahedral site. Temperature of 100, 200, and 300 K were chosen for measurement using canonical ensemble. Phase space information were proceeded to do analysis on diffusion coefficients of lithium atoms and radial distribution function graphs of lithium pair. Results showed a solid-like behavior of lithium indicating its high stability inside montmorillonites octahedral site. Very little movement was observed with slight increase over temperature rise.