Al/Co co-doped α-Ni(OH)2 samples were prepared by either ultrasonic co-precipitation method (Sample B) or co-precipitation method (Sample A). The crystal structure and particle size distribution of the prepared...Al/Co co-doped α-Ni(OH)2 samples were prepared by either ultrasonic co-precipitation method (Sample B) or co-precipitation method (Sample A). The crystal structure and particle size distribution of the prepared samples were examined by X-ray diffraction (XRD) and laser particle size analyzer, respectively. The results show that Sample B has more crystalline defects and smaller average diameter than Sample A. The cyclic voltammetry and electrochemical impedance spectroscopy measurements indicate that Sample B has better electrochemical performance than Sample A, such as better reaction reversibility, lower charge-transfer resistance and better cyclic stability. Proton diffusion coefficient of Sample B is 1.96×10-10cm2/s, which is two times as large as that (9.78×10-11cm2/s) of Sample A. The charge-discharge tests show that the discharge capacity (308 mA·h/g) of Sample B is 25 mA·h/g higher than that of Sample A (283 mA·h/g).展开更多
Spherical Ni(OH)2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni(OH)2 was investigated by scanning electron microscopy and transmission electron microscopy and co...Spherical Ni(OH)2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni(OH)2 was investigated by scanning electron microscopy and transmission electron microscopy and compared with that of traditional Ni(OH)2. The results show that the spherical nickel hydroxide consists of (Ni(OH)2) spheres with a reticulate structure of platelet-like, which is almost arranged radially and the crystalline grains intervene and connect with each other to form a three-dimensional net. The spherical Ni(OH)2 particle is full of pores, crannies between cleave planes. It is supposed that this structure is beneficial to the structural stability for the spherical particles during the charge/discharge processes and can improve the cycle life of the electrode; the pores and the crannies in spherical particles can shorten the proton diffusion distance and speed its velocity, which may result in that the local polarization is lowered. The electrochemical performances of the spherical Ni(OH)2 are improved by enhancing the conducting properties of the crystalline lattice due to its quick proton diffusion.展开更多
Biodiesel is a kind of clean and renewable energy. The effect of ethanol addition on the flame characteristics of waste oil biodiesel is studied by using OH-PLIF technique from the perspective of OH radical evolution....Biodiesel is a kind of clean and renewable energy. The effect of ethanol addition on the flame characteristics of waste oil biodiesel is studied by using OH-PLIF technique from the perspective of OH radical evolution. Ethanol addition leads to the appearance of diffusion flame reaction interface ahead of schedule and shortens the diffusion flame height. The experimental results show a linear correlation between the flame height and the fuel flow rate for a given fuel and oxidant. The same conclusion is drawn from the theoretical analysis of the approximate model. In addition. ethanol addition makes the average OH signal intensity of flame at different fuel flow rate tend to be consistent and the fuel flow rate enlarge where the flame field shows the strongest oxidation performance. Average OH signal intensity begins to weaken at larger fuel flow rate, which indicates that fuel flow rate of fuels blended with ethanol can change in larger range and does not significantly affect the uniformity of combustion.展开更多
基金Project (10774030) supported by the National Natural Science Foundation of ChinaProject (2008J1-C161) supported by the Science and Technology Program of Guangzhou City of China
文摘Al/Co co-doped α-Ni(OH)2 samples were prepared by either ultrasonic co-precipitation method (Sample B) or co-precipitation method (Sample A). The crystal structure and particle size distribution of the prepared samples were examined by X-ray diffraction (XRD) and laser particle size analyzer, respectively. The results show that Sample B has more crystalline defects and smaller average diameter than Sample A. The cyclic voltammetry and electrochemical impedance spectroscopy measurements indicate that Sample B has better electrochemical performance than Sample A, such as better reaction reversibility, lower charge-transfer resistance and better cyclic stability. Proton diffusion coefficient of Sample B is 1.96×10-10cm2/s, which is two times as large as that (9.78×10-11cm2/s) of Sample A. The charge-discharge tests show that the discharge capacity (308 mA·h/g) of Sample B is 25 mA·h/g higher than that of Sample A (283 mA·h/g).
基金Project(50134020) supported by the National Natural Science Foundation of China
文摘Spherical Ni(OH)2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni(OH)2 was investigated by scanning electron microscopy and transmission electron microscopy and compared with that of traditional Ni(OH)2. The results show that the spherical nickel hydroxide consists of (Ni(OH)2) spheres with a reticulate structure of platelet-like, which is almost arranged radially and the crystalline grains intervene and connect with each other to form a three-dimensional net. The spherical Ni(OH)2 particle is full of pores, crannies between cleave planes. It is supposed that this structure is beneficial to the structural stability for the spherical particles during the charge/discharge processes and can improve the cycle life of the electrode; the pores and the crannies in spherical particles can shorten the proton diffusion distance and speed its velocity, which may result in that the local polarization is lowered. The electrochemical performances of the spherical Ni(OH)2 are improved by enhancing the conducting properties of the crystalline lattice due to its quick proton diffusion.
基金Project(51766007)supported by the National Natural Science Foundation of ChinaProject(U1602272)supported by the NSFC-Yunnan Joint Fund Project+1 种基金Project(2015FB128)supported by the Natural Science Fund Project in Yunnan Province,ChinaProject(CNMRCUTS1704)supported by the Research Fund from State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,China
文摘Biodiesel is a kind of clean and renewable energy. The effect of ethanol addition on the flame characteristics of waste oil biodiesel is studied by using OH-PLIF technique from the perspective of OH radical evolution. Ethanol addition leads to the appearance of diffusion flame reaction interface ahead of schedule and shortens the diffusion flame height. The experimental results show a linear correlation between the flame height and the fuel flow rate for a given fuel and oxidant. The same conclusion is drawn from the theoretical analysis of the approximate model. In addition. ethanol addition makes the average OH signal intensity of flame at different fuel flow rate tend to be consistent and the fuel flow rate enlarge where the flame field shows the strongest oxidation performance. Average OH signal intensity begins to weaken at larger fuel flow rate, which indicates that fuel flow rate of fuels blended with ethanol can change in larger range and does not significantly affect the uniformity of combustion.