载铜竹炭的制备及电磁屏蔽效能

Preparation and electromagnetic shielding performance of copper-loaded bamboo charcoal

以竹炭为载体吸附Cu（NO3）2,利用Cu（NO3）2在热作用下分解为Cu O,进而与竹炭中C发生置换反应生成单质Cu,增加了竹炭的导电性,从而提高竹炭的电磁屏蔽效能。采用单因素和正交组合实验探究了炭化温度、溶液p H、吸附时间、竹炭添加量、吸附温度以及Cu（NO3）2溶液初始浓度对Cu（NO3）2在竹炭上吸附的影响,并用分析测试仪对试样进行测试和结构表征。结果表明：选用700℃的竹炭、溶液p H 6.0、吸附时间80 min、竹炭添加量0.05 g/m L、吸附温度20℃和Cu（NO3）2溶液初始浓度5 mol/L工艺条件时,竹炭中Cu元素含量达到最大,其值为152 mg/g;竹炭炭化温度和溶液吸附温度2个因子对竹炭吸附Cu（NO3）2影响最显著;在频率0~3GHz的范围内,随着竹炭中Cu元素含量的增加其电磁屏蔽效能显著提高,当Cu元素含量为152 mg/g时电磁屏蔽效能达到24 d B。

Solution of cupric nitrate（ Cu（ NO3）2） was adsorbed by bamboo charcoal and decomposed into copper oxide（ Cu O） by means of pyrolysis. Copper（ Cu） was obtained by the displacement reaction between Cu O and C of the bamboo charcoal to improve the electrical conductivity and electromagnetic shielding performance of bamboo charcoal. The effects of carbonization temperature,p H,adsorption time,addition amount of bamboo charcoal,adsorption temperatures and concentration of Cu（ NO3）2on the adsorption of Cu（ NO3）2on bamboo charcoal were studied by single factor and orthogonal methods. Atomic absorption spectroscopy,specific surface area analysis and X- Ray diffraction analysis were used to investigate properties and structure of the charcoal. The results showed that the maximum carbon content of 152 mg / g could be obtained when the carbonization temperature was 700 ℃,the p H was 6. 0,the adsorption time was 80 min,the bamboo charcoal added was 0.05 g / m L,the adsorption temperature was 20 ℃ and the concentration of the solution was 5 mol / L. The carbonization temperature and adsorption temperature were the most significant factors influencing the adsorption amount. In the frequency range of 0 to 3 GHz,the electromagnetic shielding efficiency increased significantly with the increasing of Cu content,which reached 24 d B when the Cu content was 152 mg / g.