No abstract

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.

No abstract

A new redox-active family of aromatic dicyanides was developed as organic electrodes in rechargeable batteries. The detailed electronic properties of two primary representatives of 1,4-dicyanobenzene (DCB) and 9,10-dicyanoanthracene (DCA) were studied. It is discovered that, as compared with DCB, the large aromatic π conjugation in DCA leads to better electron conductivity and more stable reduced states of DCAand DCA 2-. The Li-ion batteries with DCA electrode are shown to have highly reversible operations.

A novel polymer of PTPBQ was synthesized for the first time and could probably realize a maximum capacity of ∼390 mAh g−1 in Li-ion batteries.