Hierarchical 3D Porous Hydrogen-Substituted Graphdiyne for High-Performance Electrochemical Lithium-Ion Storage
Zengming Man, Peng Li, Shuaishuai Liu, Yuman Zhang, Xiaolin Zhu, Siyuan Ye, Wangyang Lü, Wei Chen, Guan Wu, Ningzhong Bao
Abstract
Graphdiyne (GDY) has realized significant achievements in lithium-ion batteries (LIBs) because of its unique π-conjugated skeleton with sp- and sp 2 -hybridized carbon atoms. Enriching the accessible surface areas and diffusion pathways of Li ions can realize more storage sites and rapid transport dynamics. Herein, three-dimensional porous hydrogen-substituted GDY (HsGDY) is developed for high-performance Li-ion storage. HsGDY, fabricated via a versatile interface-assisted synthesis strategy, exhibits a large specific surface area (667.9 m 2 g –1 ), a hierarchical porous structure, and an expanded interlayer space, which accelerate Li-ion accessibility and lithiation/delithiation. Owing to this high π-conjugated, conductive, and porous framework, HsGDY exhibits a large reversible capacity (930 mA h g –1 after 100 cycles at 1 A g –1 ), superior cycle (720 mA h g –1 after 300 cycles at 1 A g –1 ), and rate (490 mA h g −1 at 5 A g –1 ) performances. Density functional theory calculations of the low diffusion barrier in the lamination and vertical directions further reveal the fast Li-ion transport kinetics of HsGDY. Additionally, a LiCoO 2 –HsGDY full cell is constructed, which exhibits a good practical charge/discharge capacity of 128 mA h g –1 and stable cycling behavior. This study highlights the advanced design of next-generation LIBs to sustainably develop the new energy industry.