Honggui Deng

Synthesis of 3D hierarchical porous carbon as electrode material for electric double layer capacitors

Abstract A green and efficient method is presented to synthesize 3D hierarchical porous carbon from a metal organic framework (MOF) formed by 1,4-benzenedicarboxylic acid and zinc nitrate hexahydrate using glucose as the carbon precursor. Glucose was infiltrated into the external surface and/or voids of the cubic MOF, then polymerized and carbonized to form porous carbon. In the meantime, MOF was decomposed into ZnO, which was further reduced by carbon (or CO) into Zn that evaporated during carbonization. The morphology and pore characteristics of the products can be adjusted by changing the reaction time. When the synthesized porous carbon was used as the electrode material for electric double layer capacitors, it exhibited a high initial specific capacitance of 175 F·g−1 at 0.6 A·g−1 and a high capacitance retention of 94.2% at 12 A·g−1 in 1 mol/L NEt4BF4/propylene carbonate electrolyte.

Synthesis of porous carbons derived from metal-organic coordination polymers and their adsorption performance for carbon dioxide

A series of porous carbons (PCs) was synthesized from nonporous metal-organic coordination polymers (MOCPs), using in-situ polymerized phenol resin as a carbon precursor. The optimized PC has a BET surface area of 2 368 m2/g and an equilibrium CO2 adsorption capacity of 2.9 mmol/g at 300 K and atmospheric pressure. The porous structure of the PCs can be controlled by the formulations of the carbon precursors and gelation/aging time. Meanwhile, the evaporated Zn from the thermal decomposition of the MOCPs acts as an activation agent during carbonization, which eventually improves the microporosity of the PCs. The CO2 equilibrium adsorption capacity increases with increasing Brunauer-Emmett-Teller surface area of the PCs.

Synthesis and Electrochemical Performance of SnO 2 /Graphene Anode Material for Lithium Ion Batteries: Synthesis and Electrochemical Performance of SnO 2 /Graphene Anode Material for Lithium Ion Batteries

以氧化石墨和氯化亚锡为原料, 采用原位合成法制得SnO 2 /石墨烯纳米复合材料。该方法不需外加还原剂, 也避免了SnO 2 纳米粒子和石墨烯在机械混合过程中的团聚问题。XRD和TEM等的分析结果表明, 纳米SnO 2 颗粒都均匀地分散在石墨烯表面, 其中纳米SnO 2 的粒径和石墨烯的厚度分别为3~6 nm和1.5~2.0 nm。电化学测试结果表明: 在200 mA/g电流密度下循环100次后, SnO 2 /石墨烯负极材料的嵌锂容量可稳定在552 mAh/g, 容量保持率比单纯纳米SnO 2 提高了4.4倍; 在40、400、800 mA/g的电流密度下, SnO 2 /石墨烯负极材料的放电容量可分别保持在724.5、426.0、241.3 mAh/g, 表现出较好的倍率性能, 该结果归因于石墨烯良好的导电性及其二维纳米结构。以氧化石墨和氯化亚锡为原料, 采用原位合成法制得SnO 2 /石墨烯纳米复合材料。该方法不需外加还原剂, 也避免了SnO 2 纳米粒子和石墨烯在机械混合过程中的团聚问题。XRD和TEM等的分析结果表明, 纳米SnO 2 颗粒都均匀地分散在石墨烯表面, 其中纳米SnO 2 的粒径和石墨烯的厚度分别为3~6 nm和1.5~2.0 nm。电化学测试结果表明: 在200 mA/g电流密度下循环100次后, SnO 2 /石墨烯负极材料的嵌锂容量可稳定在552 mAh/g, 容量保持率比单纯纳米SnO 2 提高了4.4倍; 在40、400、800 mA/g的电流密度下, SnO 2 /石墨烯负极材料的放电容量可分别保持在724.5、426.0、241.3 mAh/g, 表现出较好的倍率性能, 该结果归因于石墨烯良好的导电性及其二维纳米结构。

Synthesis and Electrochemical Performance of TiO 2 /C Nanocom-posites: Synthesis and Electrochemical Performance of TiO 2 /C Nanocom-posites

以球状钛乙醇酸盐为TiO 2 前驱体, 葡萄糖作碳源, 通过水热法制得Φ(300~400) nm的TiO 2 /C复合纳米微球. 葡萄糖的浓度对产物的形貌、结构、碳含量有重要影响, 进而影响产物的电化学性能. 当碳含量为7wt%时, TiO 2 /C纳米复合材料的晶粒大小、BET比表面积、平均孔径分别为7.1 nm、157 m 2 /g和5.2 nm; 该材料用作锂离子电池负极材料时, 在0.2 C 的电流密度下循环80次后的嵌锂容量为160 mAh/g, 并且具有较好的倍率性能.以球状钛乙醇酸盐为TiO 2 前驱体, 葡萄糖作碳源, 通过水热法制得Φ(300~400) nm的TiO 2 /C复合纳米微球. 葡萄糖的浓度对产物的形貌、结构、碳含量有重要影响, 进而影响产物的电化学性能. 当碳含量为7wt%时, TiO 2 /C纳米复合材料的晶粒大小、BET比表面积、平均孔径分别为7.1 nm、157 m 2 /g和5.2 nm; 该材料用作锂离子电池负极材料时, 在0.2 C 的电流密度下循环80次后的嵌锂容量为160 mAh/g, 并且具有较好的倍率性能.