State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid-state Electronics, University of Electronic Science and Technology of China (UESTC) , Chengdu 610054, P. R. China.
State Key Laboratory of Synthetic Chemistry, Institute of Molecular Functional Materials, Department of Chemistry, The University of Hong Kong , Hong Kong 999077, P. R. China.
ACS Appl Mater Interfaces. 2017 Aug 23;9(33):27414-27420. doi: 10.1021/acsami.7b08974. Epub 2017 Aug 8.
A new family of the para-conjugated dicarboxylates embedding in biphenyl skeletons was exploited as the highly advanced organic anodes for K-ion battery. Two members of this family, namely potassium 1,1'-biphenyl-4,4'-dicarboxylate (KBPDC) and potassium 4,4'-E-stilbenedicarboxylate (KSBDC), were selectively studied and their detailed redox behaviors in K-ion battery were also clearly unveiled. Both KBPDC and KSBDC could exhibit very clear and highly reversible two-electron redox mechanism in K-ion battery, as well as higher potassiation potentials (above 0.3 V vs K/K) when compared to the inorganic anodes of carbon materials recently reported. Meanwhile, the satisfactory specific and rate capacities could be realized for KBPDC and KSBDC. For example, the KBPDC anode could realize the stable rate capacities of 165/143/135/99 mAh g under the high current densities of 100/200/500/1000 mA g, respectively, after its electronic conductivity was improved by mixing a very small amount of graphene. More impressively, the average specific capacities of ∼75 mAh g could be maintained for the KBPDC anode for 3000 cycles under the high current density of 1 A g.
一个新的联苯骨架的类共轭二羧酸酯家族被用作钾离子电池的高性能有机阳极。该家族的两个成员，即 1,1'-联苯-4,4'-二羧酸钾（KBPDC）和 4,4'-E-联苯二羧酸钾（KSBDC），被选择性地研究了，它们在钾离子电池中的详细氧化还原行为也被清楚地揭示了。KBPDC 和 KSBDC 在钾离子电池中都能表现出非常清晰和高度可逆的两电子氧化还原机制，而且与最近报道的碳材料无机阳极相比，具有更高的嵌钾电位（高于 0.3 V vs K/K）。同时，KBPDC 和 KSBDC 也能实现令人满意的比容量和倍率性能。例如，KBPDC 阳极在电子电导率通过混入少量石墨烯得到提高后，在 100/200/500/1000 mA g 的高电流密度下，可分别实现 165/143/135/99 mAh g 的稳定倍率容量。更令人印象深刻的是，KBPDC 阳极在 1 A g 的高电流密度下，经过 3000 次循环后，平均比容量仍能保持在 75 mAh g 左右。
