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Elaborately designed multifunctional electrocatalysts capable of promoting Li+ and CO2 transport are essential for upgrading the cycling stability and rate capability of Li‐CO2 batteries. Hydrogen‐bonded organic frameworks (HOFs) with open channels and easily functionalized surfaces hold great potential for applications in efficient cathodes of Li‐CO2 batteries. Herein, a robust HOFS (HOF‐FJU‐1) is introduced for the first time as a co‐catalyst in the cathode material of Li‐CO2 batteries. HOF‐FJU‐1 with cyano groups located periodically in the pore can induce homogeneous deposition of discharge products and accommodate volumetric expansion of discharge products during cycling. Besides, HOF‐FJU‐1 enables effective interaction between Ru0 nanoparticles and cyano groups, thus forming efficient and uniform catalytic sites for CRR/CER. Moreover, HOF‐FJU‐1 with regularly arranged open channels are beneficial for CO2 and Li+ transport, enabling rapid redox kinetic conversion of CO2. Therefore, the HOF‐based Li‐CO2 batteries are capable of stable operation at 400 mA g−1 for 1800 h and maintain a low overpotential of 1.96 V even at high current densities up to 5 A g−1. This work provides valuable guidance for developing multifunctional HOF‐based catalysts to upgrade the longevity and rate capability of Li‐CO2 batteries. [ABSTRACT FROM AUTHOR]

Elaborately designed multifunctional electrocatalysts capable of promoting Li+ and CO2 transport are essential for upgrading the cycling stability and rate capability of Li‐CO2 batteries. Hydrogen‐bonded organic frameworks (HOFs) with open channels and easily functionalized surfaces hold great potential for applications in efficient cathodes of Li‐CO2 batteries. Herein, a robust HOFS (HOF‐FJU‐1) is introduced for the first time as a co‐catalyst in the cathode material of Li‐CO2 batteries. HOF‐FJU‐1 with cyano groups located periodically in the pore can induce homogeneous deposition of discharge products and accommodate volumetric expansion of discharge products during cycling. Besides, HOF‐FJU‐1 enables effective interaction between Ru0 nanoparticles and cyano groups, thus forming efficient and uniform catalytic sites for CRR/CER. Moreover, HOF‐FJU‐1 with regularly arranged open channels are beneficial for CO2 and Li+ transport, enabling rapid redox kinetic conversion of CO2. Therefore, the HOF‐based Li‐CO2 batteries are capable of stable operation at 400 mA g−1 for 1800 h and maintain a low overpotential of 1.96 V even at high current densities up to 5 A g−1. This work provides valuable guidance for developing multifunctional HOF‐based catalysts to upgrade the longevity and rate capability of Li‐CO2 batteries. [ABSTRACT FROM AUTHOR]

Two Ag-MOCPs with different dimensional electron transfer Channels were used for electrocatalytic conversion CO 2 to CO. [Display omitted] • New Ag-MOCP materials for CO 2 RR electrocatalysts were synthesized. • CO 2 -to-CO conversion was boosted with the regulation of the electron transfer channel. • The FE CO for Ag-MOCP-2 with multi-dimensional electron transfer channels is higher than that for Ag-MOCP-1 with single channel at most given potentials. • The mechanism of its reaction was further explored by DFT calculation. Although, electrons transfer plays an important role in achieving the electrocatalytic CO 2 reduction reaction (CO 2 RR), it is scarce to regulate the electron transfer channels for enhancing the performance of CO 2 RR via rational design. Here, based on different solvothermal conditions, two metal–organic coordination polymers (MOCPs, Ag-MOCP-1 and Ag-MOCP-2) electrocatalyst for CO 2 RR were obtained by the same Ag ions and 5-phenyltetrazolium ligands. Single crystal X-ray diffraction showed Ag-MOCP-2 with intra-&inter-layer C H···π and π···π interactions, while Ag-MOCP-1 with intra-layer π···π interactions. The intra-&inter-layer π interactions in Ag-MOCP-2 makes it show multi-dimensional electron transfer channels, which enable Ag-MOCP-2 with higher electron conductivities and lower band gap than Ag-MOCP-1. And the Faradaic efficiency of CO for Ag-MOCP-2 with 78.3 % is higher than that for Ag-MOCP-1 with 69.1 % at −1.08 V vs RHE, and the maximum difference can reach 22 % at −1.48 V vs RHE. Based on the same central metal and organic ligands of the two MOCPs, we believe that multi-dimensional electron transfer channels make a predominant contribution for improving CO 2 RR performance in this work. [ABSTRACT FROM AUTHOR]