Zhang Li, Liu Jie, Xiao Dengji, Chen Yuhui, Zhang Shuo, Yan Liting, Gu Xin, Zhao Xuebo
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China.
School of Energy Science and Engineering, Nanjing Tech University, Nanjing, 211816, China.
Chemistry. 2023 Nov 24;29(66):e202302811. doi: 10.1002/chem.202302811. Epub 2023 Oct 12.
Reduced graphene oxide (rGO) has been demonstrated to effectively enhance the potassium storage performance of transition metal selenides due to its robust mechanical properties and high conductivity. However, the impact of rGO on the electrode-electrolyte interface, a crucial factor in the electrochemical performance of potassium-ion batteries (PIBs), requires further exploration. In this study, we synthesized a seamless architecture of rGO on FeSe/C nanocrystals (FeSe/C@rGO). Comparative analysis between FeSe/C and FeSe/C@rGO reveals that the rGO layer exhibits robust adsorption energies towards EC and DEC, inducing the formation of organic-rich solid-electrolyte interphase (SEI) without damage to the structural integrity. Furthermore, incorporating rGO triggers K -ions into the double electrode layer (EDL), markedly improving the transport of K -ions. As a PIB anode, FeSe/C@rGO exhibits a reversible capacity of 332 mAh g at 200 mA g after 300 cycles, along with excellent long-term cycling stability, showcasing an ultralow decay rate of only 0.086 % per cycle after 1900 cycles at 1000 mA g .
还原氧化石墨烯（rGO）已被证明因其强大的机械性能和高导电性而能有效提升过渡金属硒化物的钾存储性能。然而，rGO对电极-电解质界面（这是钾离子电池（PIB）电化学性能的关键因素）的影响仍需进一步探索。在本研究中，我们在FeSe/C纳米晶体（FeSe/C@rGO）上合成了一种无缝的rGO结构。FeSe/C和FeSe/C@rGO之间的对比分析表明，rGO层对碳酸乙烯酯（EC）和碳酸二乙酯（DEC）具有强大的吸附能，可诱导形成富有机的固体电解质界面（SEI），而不会破坏结构完整性。此外，引入rGO会促使钾离子进入双电层（EDL），显著改善钾离子的传输。作为PIB负极，FeSe/C@rGO在200 mA g下经过300次循环后，可逆容量为332 mAh g，同时具有出色的长期循环稳定性，在1000 mA g下经过1900次循环后，展示出仅0.086%/循环的超低衰减率。
