Study on preparation of Cu(OH)2 nano-fibers by chemical precipitation
The Cu(OH)2 nano-fibers were prepared by chemical precipitation taken CuSO4·5H2O and NaOH as raw materials. The experimental results reveal that conditions of the chemical precipitation were that: the concentration of CuSO4 solution was 0.1 mol·L-1, that of NaOH solution was 4 mol·L-1. the dropping rate of NaOH solution was 50 ml·min-1, the reaction temperature was 20℃, the pH value of the reaction end was larger than 13, the stirring rate was 1200 r·min-1. The Cu(OH)2 nano-fibers have a diameter of 10～40 nm and a length of 1～6 μm. The quantity and length of the nano-fibers of Cu(OH)2 increase with the stirring rate. When the stirring rate was 1200 r·min-1, the Cu(OH)2 is fiber-like. The reason is that when the stirring rate increases, the contacting probability of Cu(OH)2 particle in the direction of the linear velocity increases, so that the growing rate of the crystalline in the direction is much larger than that in the transverse direction, through which the final product is easy to form fibers. The quantity and length of the nano-fibers of Cu(OH)2 increase with the pH of the reaction end. When the pH of the reaction end was 13, the Cu(OH)2 is fiber-like. The superfluous alkali in the solution acted as a surfactant, which made the probability of collision among the molecules or particles of the Cu(OH)2 greatly decrease and not easily form a larger particle. Therefore the product is formed fibers. The quantity and length of the nano-fibers of Cu(OH)2 increase with the dropping rate. When the pH of the dropping rate was 50 ml·min-1, the Cu(OH)2 is fiber-like. When NaOH was quickly dripped, the supersaturated alkali in the local solution made the cores of the crystalline grow quickly. Around the produced Cu(OH)2 the superfluous alkali, as a surfactant, impeded growing of the particles. Owing to the strong stirring, the particles are easily to stretch along the direction of linear velocity to form fibers. The authors understand that in the range of 30～120 min, the reaction time has little effect on the product. So the reaction time was determined as 30 min. This means that the nano-Cu(OH)2 having very high activity, when it is radiated by high reaction temperature, will decompose to CuO and H2O. So the reaction time was determined as 20℃.
Cu(OH)2 nano-fibers chemical precipitation
GONG Pan-wei LI Zai-yuan ZHAI Yu-chun
School of Materials and Metallurgy,Northeastern University,Shenyang,110004,China;School of Petroleum School of Materials and Metallurgy,Northeastern University,Shenyang,110004,China
国际会议
成都
英文
2007-11-19（万方平台首次上网日期，不代表论文的发表时间）