Qiao Fan, Wang Junjun, Yu Ruohan, Huang Meng, Zhang Lei, Yang Wei, Wang Hong, Wu Jinsong, Zhang Lei, Jiang Yalong, An Qinyou
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, People's Republic of China.
Hainan Institute, Wuhan University of Technology, Sanya 572000, People's Republic of China.
ACS Nano. 2023 Nov 28;17(22):23046-23056. doi: 10.1021/acsnano.3c08645. Epub 2023 Nov 7.
Calcium-ion batteries are an emerging energy storage device owing to the low redox potential of Ca/Ca and the naturally abundant reserves of the Ca element. However, the high charge density and large radius of Ca lead to a low calcium storage capacity or unsatisfactory cycling performance for most electrode materials. Herein, we report the organic crystal 3,4,9,10-perylenetetracarboxylic diimide (PTCDI) as an anode material for aqueous calcium-ion batteries (ACIBs) in a water-in-salt electrolyte. PTCDI delivers a high discharge capacity of 131.8 mAh g, excellent rate performance (86.2 mAh g@10000 mA g), and an ultralong life of 68000 cycles (over 470 days) with a high capacity retention of 72.7%. The calcium storage mechanism of PTCDI is shown to be an enolization reaction by attenuated total reflectance Fourier-transform infrared and X-ray photoelectron spectroscopy. The activation mechanism of PTCDI microribbon splitting along the (020) crystal plane is studied by X-ray diffraction, 3D tomography reconstruction technologies, and transmission electron microscopy. In addition, the Ca storage sites and diffusion pathways of PTCDI are studied by density functional theory calculations. Finally, by matching a high-voltage Prussian blue analogue cathode, the assembled aqueous calcium-ion full cells exhibit excellent wide-temperature operating capability (-20 to +50 °C) and an ultralong life of 30000 cycles. Further, an aqueous calcium-ion pouch cell is constructed and exhibits a long lifetime of over 500 cycles.
由于Ca/Ca的低氧化还原电位以及Ca元素天然丰富的储量，钙离子电池是一种新兴的储能装置。然而，Ca的高电荷密度和大半径导致大多数电极材料的钙存储容量低或循环性能不理想。在此，我们报道了有机晶体3,4,9,10-苝四羧酸二酰亚胺（PTCDI）作为水系钙离子电池（ACIBs）在盐包水电解质中的负极材料。PTCDI具有131.8 mAh g的高放电容量、优异的倍率性能（10000 mA g时为86.2 mAh g）以及68000次循环（超过470天）的超长寿命，容量保持率高达72.7%。通过衰减全反射傅里叶变换红外光谱和X射线光电子能谱表明，PTCDI的钙存储机制是烯醇化反应。通过X射线衍射、三维断层扫描重建技术和透射电子显微镜研究了PTCDI微带沿（020）晶面分裂的活化机制。此外，通过密度泛函理论计算研究了PTCDI的钙存储位点和扩散途径。最后，通过匹配高压普鲁士蓝类似物正极，组装的水系钙离子全电池表现出优异的宽温度工作能力（-20至+50°C）和30000次循环的超长寿命。此外，构建了一个水系钙离子软包电池，其寿命超过500次循环。
