Theoretical and Physical Chemistry Institute, National Hellenic Research, Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
ACS Nano. 2010 Dec 28;4(12):7499-507. doi: 10.1021/nn101735e. Epub 2010 Nov 16.
Efficient exfoliation of graphite flakes by sonicating them in benzylamine was accomplished, affording stable suspensions of few-layers graphene. The latter were chemically modified following the Bingel reaction conditions, with the aid of microwave irradiation, producing highly functionalized graphene-based hybrid materials. The resulting hybrid materials, possessing cyclopropanated malonate units covalently grafted onto the graphene skeleton, formed stable suspensions for several days in a variety of organic solvents and were characterized by diverse and complementary spectroscopic, thermal, gravimetric, and high-resolution electron microscopy techniques. When a malonate derivative, bearing the electro-active extended tetrathiafulvalene (exTTF) moiety, was synthesized and used for the functionalization of graphene, energy dispersive X-ray (EDX) analysis verified the presence of sulfur in the corresponding graphene-based hybrid material. Moreover, the redox potentials of the exTTF-graphene hybrid material were determined by electrochemistry, while the formation of a radical ion pair that includes one-electron oxidation of exTTF and one-electron reduction of graphene was suggested with the energy gap of (graphene)(•-)-(exTTF)(•+) being calculated as 1.23 eV.
通过在苄胺中超声处理石墨片，实现了石墨片的高效剥离，得到了几层石墨烯的稳定悬浮液。然后，在微波辐射的辅助下，根据 Bingel 反应条件对其进行化学修饰，得到了高度官能化的基于石墨烯的杂化材料。所得的杂化材料具有丙二酸盐单元共价接枝到石墨烯骨架上的环丙烷化部分，在多种有机溶剂中可稳定悬浮数天，并通过多种互补的光谱、热重、重量分析和高分辨率电子显微镜技术进行了表征。当合成并使用含有电活性扩展四硫富瓦烯（exTTF）部分的丙二酸盐衍生物对石墨烯进行功能化时，能量色散 X 射线（EDX）分析证实了相应的基于石墨烯的杂化材料中存在硫。此外，通过电化学确定了 exTTF-石墨烯杂化材料的氧化还原电位，并且通过计算得出包括 exTTF 的单电子氧化和石墨烯的单电子还原的自由基离子对的形成，其中（石墨烯）（•-）-（exTTF）（•+）的能隙为 1.23 eV。
