Bottom‐Up Fabrication of 1D Cu‐based Conductive Metal–Organic Framework Nanowires as a High‐Rate Anode towards Efficient Lithium Storage

Abstract

Conductive metal–organic frameworks (MOFs), as a newly emerging multifunctional material, hold enormous promise in electrochemical energy‐storage systems owing to their merits including good electronic conductivity, large surface area, appropriate pore structure, and environmental friendliness. In this contribution, a scalable solvothermal strategy was devised for the bottom‐up fabrication of 1D Cu‐based conductive MOF, that is, Cu3(2,3,6,7,10,11‐hexahydroxytriphenylene)2 (Cu‐CAT) nanowires (NWs), which were further utilized as a competitive anode for lithium‐ion batteries (LIBs). The intrinsic Li storage mechanism of the Cu‐CAT electrode was also explored. Benefiting from its structural virtues, the resultant 1D Cu‐CAT NWs were endowed with superb Li+ diffusion coefficients and electrochemical conductivities and exhibited remarkably high‐rate reversible capacities of approximately 631 mAh g−1 at 0.2 A g−1 and even approximately 381 mAh g−1 at 2 A g−1, along with striking capacity retention of 81 % after 500 cycles at 0.5 A g−1. In addition, a Cu‐CAT NWs‐based full cell assembled with LiNi0.8Co0.1Mn0.1O2 as the cathode displayed a large energy density of approximately 275 Wh kg−1 as well as excellent cycling behavior. These results manifest the promising application of 1D conductive Cu‐CAT NWs in advanced LIBs and even other potential versatile energy‐related fields.

Metal‐organic Framework of [Cu2(BIPA‐TC)(DMA)2]n: A Promising Anode Material for Lithium‐Ion Battery

“…Obviously, the semicircle of the Cu–MOF cell slightly increased after 50 cycles, indicating that the SEI formed on the electrode became thicker but significantly stable. This result can support the superior performance in LIBs, especially for the excellent cyclability (Figure ) . However, the slope of lines at low frequency region, corresponding to Warburg impedance (W), was found to be different before and after cycling .…”

“…However, these three peaks almost disappeared in the subsequent cycle because the lithiation of MOF was only semi‐reversible with the more Li + insertion into the Cu–MOF, and the repulsion (e − ) between the charges would increase, resulting in no spikes in subsequent cycles. During the anodic scan, two broad peaks were found at 0.81 and 1.75 V due to the lithium release from the carboxylate moieties . From the second cycle, the subsequent CV curves showed no remarkable change, demonstrating great reversibility of redox reaction.…”

Recent advances in process engineering and upcoming applications of metal–organic frameworks

“…In 2019, Guo and coworkers reported novel one-dimensional (1D) copper-based MOF nanowires (Cu-CAT NWs) that exhibited good performance as anode materials for LIBs [365] . The unique 1D structural features and bimodal pores led to a high electronic conductivity and large Li ion diffusion coefficients.…”

Conductive metal‐organic frameworks: Recent advances in electrochemical energy‐related applications and perspectives

“… 72 The Cu 3 (HHTP) 2 also exhibits good long‐term cycling stability with a retained capacity of about 540 mAh/g after 500 cycles at 500 mAh/g (Figure 5E). 70 Especially, the transmission electron microscopy (TEM) images of Ni 3 (HHTP) 2 after 300 cycles show that although its morphology has changed, it still maintains the 1D NR structure, indicating the good structural stability 72 . The change of peak intensity in the ex situ X‐ray diffraction (XRD) pattern during the first charge and discharge also shows its stable crystal structure 72 .…”

“…Due to the special 2D layered structure and uniform pores, the conductive M 3 (HHTP) 2 is endowed with more effective active sites for Li + storage. More significantly, the lithium storage sites of the MOFs are tentatively put forward with XPS and ex situ XRD technique as the three types, that is, (a) benzene ring, (b) pores, and (c) interlaminar space, as schematically depicted in Figure 5G 70‐72 . Besides, the NiTIB and CuTIB, as potential anodes, render high discharge capacities of approximately 193 and approximately 98 mAh/g, respectively, within a working voltage range from 0.8 to 2.0 V (vs Li + /Li) at a current density of 50 mA/g 39 …”