Decreasing the Overpotential of Aprotic Li‐CO₂ Batteries with the In‐Plane Alloy Structure in Ultrathin 2D Ru‐Based Nanosheets

Abstract

The aprotic Li-CO 2 battery is emerging as a promising energy storage technology with the capability of CO 2 fixation and conversion. However, its practical applications are still impeded by the large overpotential. Herein, the general synthesis of a series of ultrathin 2D Ru-M (M = Co, Ni, and Cu) nanosheets by a facile one-pot solvothermal method is reported. As a proofof-concept application, the representative RuCo nanosheets are used as the cathode catalysts for Li-CO 2 batteries, which demonstrate a low charge voltage of 3.74 V, a small overpotential of 0.94 V, and hence a high energy efficiency of 75%. Ex/in situ studies and density functional theory calculations reveal that the excellent catalytic performance of RuCo nanosheets originates from the enhanced adsorption toward Li and CO 2 during discharge as well as the elevated electron interaction with Li 2 CO 3 during charge by the in-plane RuCo alloy structure. This work indicates the feasibility of boosting the electrochemical performance of Li-CO 2 batteries by in-plane metal alloy sites of ultrathin 2D alloy nanomaterials.

Binuclear Cu complex catalysis enabling Li–CO2 battery with a high discharge voltage above 3.0 V

“…4b , the battery exhibits robust cycle stability over 400 cycles. The discharge voltage (3.01 V) and energy efficiency (75.4%) of this work are the best results among the reported solid or liquid catalysts during full discharge-recharge process at the current density of 100 mA g −1 25 , 28 , 56 – 61 (Fig. 4c ).…”

“…b Cyclic performance of the Li–CO 2 battery with a Cu(I) RM-based electrolyte and a Ru@Super P cathode under a fixed specific capacity of 1000 mAh g −1 at a current density of 200 mA g −1 . c Comparison of discharge voltage and energy efficiency with other reported catalysts for Li–CO 2 batteries in recent reports 25 , 28 , 56 – 61 . d Schematic of the synergetic effect of Cu(I) RM and Ru catalysts for the Li–CO 2 battery system.…”

Defect engineering of two-dimensional materials for advanced energy conversion and storage

“…30g–j). 532 As a representative, fine structure investigations suggested that the obtained 2D RuCo nanosheets endowed a lower Ru–Ru coordination number but a relatively higher Ru–Co coordination number compared to the RuCo nanoparticles. Numerous in-plane active alloy sites would remarkably facilitate the adsorption toward Li and CO 2 to accelerate the CO 2 RR reaction and improve the electron interactions with discharge products to enhance CO 2 ER reaction kinetics.…”

Electrocatalytic Reduction of Carbon Dioxide to High-Value Multicarbon Products with Metal–Organic Frameworks and Their Derived Materials

“…The heavy reliance of anthropogenic activities and industrialization on fossil fuels has dramatically increased the concentrations of atmospheric greenhouse gases, especially carbon dioxide (CO 2 ). − Growing concern in the areas of global warming, extreme weather, climate change, and energy crisis is driving research on efficient CO 2 conversion to achieve carbon neutrality. − Given the advantage of being able to be powered by renewable electricity, the electrocatalytic CO 2 reduction reaction (CO 2 RR) has emerged as one of the most promising and sustainable methods to convert CO 2 to valuable chemicals and fuels, especially highly valuable multicarbon (C 2+ ) products like ethylene (C 2 H 4 ), acetic acid (CH 3 COOH), ethanol (C 2 H 5 OH), and n-propanol ( n -C 3 H 7 OH). − Among various types of electrocatalysts, copper (Cu)-based materials exhibited the most efficient electrochemical CO 2 conversion toward C 2+ products. − To date, great effort, such as composition regulation, − morphology adjustment, , defect control, − strain modulation, , and phase engineering, − has been devoted to modulating Cu-based electrocatalysts to boost the C 2+ production in CO 2 RR. However, due to the multiple electron-transfer processes and competitive reactions, it is still challenging to regulate the CO 2 RR reaction pathway toward C 2+ products. − Meanwhile, most CO 2 RR electrocatalysts still demonstrate inferior activity, poor selectivity and low stability that limit the industry-scale applications. − Hence, it is critically important to explore novel high-performance CO 2 RR electrocatalysts to efficiently convert CO 2 molecules to C 2+ products.…”