Rechargeable Li-CO2 Batteries Research Articles

Improving the Rechargeable Li-CO2 Battery Performances by Tailoring Oxygen Defects on Li-Ni-Co-Mn Multi-Metal Oxide Catalysts Recycled from Spent Ternary Lithium-Ion Batteries.

Rechargeable Li-CO2 batteries are considered as a promising carbon-neutral energy storage technology owing to their ultra-high energy density and efficient CO2 capture capability. However, the sluggish CO2 reduction/evolution kinetics impedes their practical application, which leads to huge overpotentials and poor cyclability. Multi-element transit metal oxides (TMOs) are demonstrated as effective cathodic catalysts for Li-CO2 batteries. But there are no reports on the integration of defect engineering on multi-element TMOs. Herein, the oxygen vacancy-bearing Li-Ni-Co-Mn multi-oxide (Re-NCM-H3) catalyst with the α-NaFeO2-type structure is first fabricated by annealing the NiCoMn precursor that derived from spent ternary LiNi0.8Co0.1Mn0.1O2 cathode, in H2 at 300°C. As demonstrated by experimental results and theory calculations, the introduction of moderate oxygen vacancy has optimized electronic state near the Fermi level (Ef), eventually improving CO2 adsorption and charge transfer. Therefore, the Li-CO2 batteries with Re-NCM-H3 catalyst deliver a high capacity (11808.9 mAh g-1), a lower overpotential (1.54V), as well as excellent stability over 216 cycles at 100mA g-1 and 165 cycles at 400mA g-1. This study not only opens up a sustainable application of spent ternary cathode, but also validates the potential of multi-element TMO catalysts with oxygen defects for high-efficiency Li-CO2 batteries.

Ultrafine Ru nanoparticles anchored on N-doped mesoporous hollow carbon spheres as a highly efficient bifunctional catalyst for Li–CO2 batteries

Rechargeable Li–CO2 battery is a facilitative and promising device for the conversion of CO2 to electrochemical energy. However, it remains a challenge to enhance the sluggish decomposition kinetics of lithium carbonate as the discharge product. Herein, the Ru nanoparticles anchored on N-doped mesoporous hollow carbon nanospheres (Ru-AHCNs) are designed as cathode to enhance the electrochemical performance of Li–CO2 battery. The Ru-AHCNs cathode displays a high discharge specific capacity of 11194.4 mA h g−1 at the current density of 100 mA g−1. In addition, the Ru-AHCNs cathode can stably run over 50 cycles and maintain a small overpotential (<1.38 V) with a limited capacity of 1000 mA h g−1 at 100 mA g−1. The excellent stability and catalytic activity of the cathode are ascribed to the following factors: (i) Uniform deposition of Ru nanoparticles in hollow carbon nanospheres can enhance the decomposition of Li2CO3 and provide considerable exposure to active sites. (ii) N-doped mesoporous hollow carbon nanospheres can provide abundant electron transport channels and promote the nucleation of discharge products. These results evidently prove the reversible formation and decomposition of the discharge products, indicating that Ru-AHCNs cathode possesses excellent bifunctional catalytic activity.

Unique Hierarchically Structured High-Entropy Alloys with Multiple Adsorption Sites for Rechargeable Li-CO2 Batteries with High Capacity.

Lithium-carbon dioxide (Li-CO2) batteries offer the possibility of synchronous implementation of carbon neutrality and the development of advanced energy storage devices. The exploration of low-cost and efficient cathode catalysts is key to the improvement of Li-CO2 batteries. Herein, high-entropy alloys (HEAs)@C hierarchical nanosheet is synthesized from the simulation of the recycling solution of waste batteries to construct a cathode for the first time. Owing to the excellent electrical conductivity of the carbon material, the unique high-entropy effect of the HEAs, and the large number of catalytically active sites exposed by the hierarchical structure, the FeCoNiMnCuAl@C-based battery exhibits a superior discharge capability of 27664 mAh g-1 and outstanding durability of 134 cycles as well as low overpotential with 1.05V at a discharge/recharge rate of 100mA g-1. The adsorption capacity of different sites on the HEAs is deeply understood through density functional theory calculations combined with experiments. This work opens up the application of HEAs in Li-CO2 batteries catalytic cathodes and provides unique insights into the study of adsorption active sites in HEAs.

Reconfiguration of the charge density difference of nitrogen-doped graphene by covalently bonded Cu-N4 active sites boosting thermodynamics and performance in aprotic Li-CO2 battery

The slow kinetics of the CO2 reduction and evolution reactions in the Li-CO2 battery result in a high overpotential, low energy efficiency and undesired life. Exploring the durable electrocatalysts with high activity for CO2 reduction and evolution processes in aprotic Li-CO2 batteries is of great significance for CO2 capture and utilization. Herein, single-atom copper uniformly anchored on nitrogen-doped graphene (SA-Cu-NG) was demonstrated as a durable catalyst for the rechargeable Li-CO2 battery. The resulting Li-CO2 battery shows a remarkable specific capacity of 29033 mAh g−1 at 100 mA g−1, an ultra-long life up to 538 cycles (over 2730 h), and a low overpotential of 1.47 V (1000 mA g−1), outperforming the reported Li-CO2 batteries. The X-ray absorption fine structure analysis of SA-Cu-NG unravels that the covalent effect between Cu and N, which exists in the form of Cu-N4 in nitrogen-doped graphene. Further, it is theoretically elucidated that the covalent effect of Cu-N4 leads to the reconfiguration of the charge density difference on nitrogen-doped graphene, thereby improving the adsorption of CO2 and weakening the decomposition barrier of the discharge products on the surface single-atom copper, thus optimizing the nucleation decomposition process. In conclusion, the exceptional performances of Li-CO2 battery are attributed to the superior catalytic activity on Cu-N4 sites and the excellent electronic conductivity of nitrogen-doped graphene, activating the reversible process of discharge product formation and decomposition.

MOF-Derived CoSe2 Nanoparticles/Carbonized Melamine Foam as Catalytic Cathode Enabling Flexible Li-CO2 Batteries with High Energy Efficiency and Stable Cycling.

Rechargeable aprotic Li-CO2 batteries have aroused worldwide interest owing to their environmentally friendly CO2 fixation ability and ultra-high specific energy density. However, its practical applications are impeded by the sluggish reaction kinetics and discharge product accumulation during cycling. Herein, a flexible composite electrode comprising CoSe2 nanoparticles embedded in 3D carbonized melamine foam (CoSe2 /CMF) for Li-CO2 batteries is reported. The abundant CoSe2 clusters can not only facilitate CO2 reduction/evolution kinetics but also serve as Li2 CO3 nucleation sites for homogeneous discharge product growth. The CoSe2 /CMF-based Li-CO2 battery exhibits a large initial discharge capacity as high as 5.62mAhcm-2 at 0.05mAcm-2 , a remarkably small voltage gap of 0.72V, and an ultrahigh energy efficiency of 85.9% at 0.01mAcm-2 , surpassing most of the noble metal-based catalysts. Meanwhile, the battery demonstrates excellent cycling stability of 1620h (162 cycles) at 0.02mAcm-2 with an average overpotential of 0.98V and energy efficiency of 85.4%. Theoretical investigations suggest that this outstanding performance is attributed to the suitable CO2 /Li adsorption and low Li2 CO3 decomposition energy. Moreover, flexible Li-CO2 pouch cell with CoSe2 /CMF cathode displays stable power output under different bending deformations, showing promising potential in wearable electronic devices.

Gas concentration-driven LiOH chemistry in Li-CO2 batteries

In conventional Li-CO2 batteries, Li2CO3 is an intractable discharge product due to its wide bandgap. To this end, researchers have focused more attention on the decomposition of Li2CO3 in order to reduce the high charge potential. However, even the kinetics of CO2 evolution process can be accelerated, Li2CO3 will still passivate the cathodes, which in turn affects the cycle life of Li-CO2 batteries. Here, we designed a CO2 partly-absent Li-CO2 battery, the concentration of CO2 involved during the discharge process is reduced, then the discharge potential of this battery can be moved to 2.1 V. Furthermore, the discharge product of this CO2 partly-absent Li-CO2 battery is proved to be LiOH instead of Li2CO3, it can be recharged at a low potential of 3.5 V benefit from the readily degradable product (LiOH). In this Li-CO2 battery, the effect of gas concentration on discharge process is studied firstly, and totally different results are discussed, offering new insights into the material design and the development of reliable rechargeable Li-CO2 batteries in the future.

Recent advancement in designing catalysts for rechargeable Li–CO2 batteries

This review presents recent advances and critical scientific challenges in designing cathodic catalysts for rechargeable Li–CO2 batteries.

Improved Cycle Performance of Li-CO2 Batteries with Nickel Manganite Supported Carbon Nanotube NiMn2O4 @CNT Cathode

Rechargeable Li-CO2 batteries have emerged as promising candidates for next generation batteries due to their low cost, high theoretical capacity, and ability to capture the greenhouse gas CO2. However, these batteries still face challenges such as slow reaction kinetic and short cycle performance due to the accumulation of discharge products. To address this issue, it is necessary to design and develop high efficiency electrocatalysts that can improve CO2 reduction reaction. In this study, we report the use of NiMn2O4 electrocatalysts combined with multiwall carbon nanotubes as a cathode material in the Li-CO2 batteries. This combination proved effective in decomposing discharge products and enhancing cycle performance. The battery shows stable discharge–charge cycles for at least 30 cycles with a high limited capacity of 1000 mAh g−1 at current density of 100 mA g−1. Furthermore, the battery with the NiMn2O4@CNT catalyst exhibits a reversible discharge capacity of 2636 mAh g−1. To gain a better understanding of the reaction mechanism of Li-CO2 batteries, spectroscopies and microscopies were employed to identify the chemical composition of the discharge products. This work paves a pathway to increase cycle performance in metal-CO2 batteries, which could have significant implications for energy storage and the reduction of greenhouse gas emissions.

High-Performance Li-CO2 Battery Based on Carbon-Free Porous Ru@QNFs Cathode.

Lithium-carbon dioxide (Li-CO2 ) batteries have attracted much attention due to their high theoretical energy density. However, due to the existance of lithium carbonate and amorphous carbon in the discharge products that are difficult to decompose, the battery shows low coulombic efficiency and poor cycle performance. Here, by adjusting the adsorption of carbon dioxide (CO2 )on ruthenium (Ru) catalysts surface, this work reports an ultralow charge overpotential and long cycle life Li-CO2 battery that consists of typical lithium metal, ternary molten salt electrolyte (TMSE), and Ru-based cathode. Experimental results show that the Ru catalysts deposited on quartz nanofiber (QF) can suppress the four-electron conversion of CO2 to lithium carbonate (Li2 CO3 ). As a result, the battery shows a long-cycle-life of over 457 cycles at 1.0 A g-1 with a limited capacity of 500 mAh g-1 Ru . Remarkably, a recorded low discharge potential of ≈3.0V has been achieved after 35 cycles at 0.5 A g-1 , with a charge potential retention of over 99%. Moreover, the battery can operate over 25 A g-1 and recover 96% potential. This battery technology paves the way for designing high-performance rechargeable Li-CO2 batteries with carbon neutrality.

Dual Catalytic Sites of Alloying Effect Bloom CO2 Catalytic Conversion for Highly Stable Li–CO2 Battery

AbstractOwing to the ingenious utilization of CO2 conversion electrochemistry, rechargeable Li–CO2 batteries, have attracted more and more attention. However, the large potential polarization resulting from the sluggish CO2 reduction/evolution electrochemistry degrades energy efficiency and cycling performance. One possibility to break the kinetic bottlenecks of ‐Li–CO2 batteries is to design high‐efficiency catalysts with flexible geometric and electronic structures. Herein, an efficient synergistic catalyst with unique alloyed dual catalytic sites composed of uniformly ultrafine Ir–Ru alloyed nanoparticles modified nitrogen‐doped carbon nanotube composite (denoted as IrRu/N‐CNT) is synthesized. Combining the synergistic effect between the remarkably enhanced catalytic activity of Ir–Ru dual catalytic sites, the Li–CO2 battery delivers a high discharge capacity of 6228 mAh g−1 and outstanding stability over 7660 h. Density functional theory (DFT) calculation results uncover that the excellent electrochemical performance is ascribed to the novel dual catalytic sites on the surface of IrRu nanoalloys, which effectively modify its electronic structures and shorten the electron transfer pathway, leading to the deposition of film‐like Li2CO3 products. This study highlights the novel view of building a dual catalytic site and provides some new insights for understanding the catalytic mechanism of an alloying‐type bifunctional catalyst toward realizing high‐performance Li–CO2 batteries.

Graphdiyne scaffold anchored highly dispersed ruthenium nanoparticles as an efficient cathode catalyst for rechargeable Li–CO2 battery

Lithium (Li)–CO2 battery is rising as an attractive energy-storage system with the competence of CO2 conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herein, a rational design on a highly catalytic Li–CO2 battery electrode built by graphdiyne powder as a multi-functional laminar scaffold with anchored highly dispersed Ru nanoparticles is explored. The strong interaction between the abundant acetylenic bond sites of graphdiyne scaffold and Ru nanoparticles can effectively promote the electrochemical progress and reduce the voltage polarization. The unique channels architecture of the cathodic catalyst with enough space not only accelerates CO2 diffusion and electrons/Li+ transport, but also allows a large amount of accommodation for discharged product (Li2CO3) to assure an advanced capacity. The corresponding Li–CO2 battery displays an advanced discharged capacity of 15,030 mAh/g at 500 mA/g, great capacity retention of 8873 mAh/g at 2 A/g, high coulombic efficiency of 97.6% at 500 mA/g and superior life span for 120 cycles with voltage gap of 1.67 V under a restricted capacity of 1000 mAh/g at 500 mA/g. Ex/in-situ studies prove that synergy between Ru nanoparticles and acetylene bonds of GDY can boost the round-trip CO2RR and CO2ER kinetics.

Single‐Atom Cadmium‐N4 Sites for Rechargeable Li–CO2 Batteries with High Capacity and Ultra‐Long Lifetime

AbstractThe rechargeable Li–CO2 battery shows great potential in civil, military, and aerospace fields due to its high theoretical energy density and CO2 capture capability. To facilitate the practical application of Li–CO2 battery, the design of efficient, low‐cost, and robust non‐noble metal cathodes to boost CO2 reduction/evolution kinetics is highly desirable yet remains a challenge. Herein, single‐atom cadmium is reported with a Cd‐N4 coordination structure enable rapid kinetics of both the discharge and recharge process when employed as a cathode catalyst, and thus facilitates exceptional rate performance in a Li–CO2 battery, even up to 10 A g−1, and remains stable at a high current density (100 A g−1). An unprecedented discharge capacity of 160045 mAh g−1 is attained at 500 mA g−1. Excellent cycling stability is maintained for 1685 and 669 cycles at 1 A g−1 and capacities of 0.5 and 1 Ah g−1, respectively. Density functional theory calculations reveal low energy barriers for both Li2CO3 formation and decomposition reactions during the respective discharge and recharge process, evidencing the high catalytic activity of single Cd sites. This study provides a simple and effective avenue for developing highly active and stable single‐atom non‐precious metal cathode catalysts for advanced Li–CO2 batteries.

Suppression of CO2 induced lithium anode corrosion by fluorinated functional group in quasi-solid polymer electrolyte enabling long-cycle and high-safety Li-CO2 batteries

Given high theoretical energy density and environmental-friendly CO2 fixation ability, rechargeable Li-CO2 battery is explored as a promising energy storage device. However, its cycling stability and safety are challenged by the continuous pulverization of Li anode and the leakage of liquid electrolytes (LEs). Herein, a quasi-solid polymer electrolyte (QSPE) with -CF3 functional groups was designed and in-situ fabricated for Li-CO2 battery. The solidification of electrolyte avoids the leakage of LEs and effectively inhibits the diffusion of the acid CO2 and cathode by-products to etch Li anode. Besides, the introduction of -CF3 can construct a fish scale-like LiF-rich solid electrolyte interface on Li anode, which induces the uniform and dense deposition of Li to inhibit the deeper Li from being further etched. The QSPE also exhibits high ion conductivity (1.98×10−3 S cm−1 at 25°C), enhanced Li+ transport number (0.47), and superb stability (>5.27 V vs. Li/Li+). Consequently, the Li-CO2 battery with QSPE delivers effectively suppressed pulverization of Li anode, extraordinary cyclic stability over 295 cycles (1250 h) at 50 μA cm−2, and lower overpotential (1.05 V) compared to the cells with LE. Moreover, the as-prepared QSPE also demonstrates excellent application potential in other Li metal batteries and flexible electronic devices.

A flexible Li-CO2 batteries with enhanced cycling stability enabled by a IrO2/carbon fiber self-standing cathode

Rechargeable Li-CO2 batteries provide a very promising approach to simultaneously solve energy shortage and the greenhouse effect. However, Li-CO2 batteries are facing several shortcomings, especially the slow CO2 oxidation and reduction kinetics, which deteriorate the energy efficiency and cycling life. Herein, IrO2/carbon fibers derived from kapok (IrO2/CK) are prepared via simple one-step carbonization and subsequent hydrothermal reaction. Benefitting from the favorable CO2 reduction and evolution catalytic activities of the loaded IrO2 nanoparticles, the enhanced electron transfer and reactants diffusion kinetics derived by the unique cross-linked hierarchical porous structure and the ample space for Li2CO3 deposition, the fabricated Li-CO2 battery, IrO2/CK as the cathode, shows ultra-long operation time more than 4000 h. More importantly, the cathode exhibits excellent mechanical flexibility conferred by the kapok, which can maintain the original structure during bending. The pouch-type flexible Li-CO2 battery with IrO2/CK cathode can steadily operate for 300 h under different bending conditions. This work will advance the development of flexible Li-CO2 batteries in the field of wearing energy storage devices.

Isolated Metalloid Tellurium Atomic Cluster on Nitrogen-Doped Carbon Nanosheet for High-Capacity Rechargeable Lithium-CO2 Battery.

Rechargeable Li-CO2 battery represents a sustainable technology by virtue of CO2 recyclability and energy storage capability. Unfortunately, the sluggish mass transport and electron transfer in bulky high-crystalline discharge product of Li2 CO3 , severely hinder its practical capacity and rechargeability. Herein, a heterostructure of isolated metalloid Te atomic cluster anchored on N-doped carbon nanosheets is designed (TeAC @NCNS) as a metal-free cathode for Li-CO2 battery. X-ray absorption spectroscopy analysis demonstrates that the abundant and dispersed Te active centers can be stabilized by C atoms in form of the covalent bond. The fabricated battery shows an unprecedented full-discharge capacity of 28.35mAhcm-2 at 0.05mAcm-2 and long-term cycle life of up to 1000h even at a high cut-off capacity of 1mAhcm-2 . A series of ex situ characterizations combined with theoretical calculations demonstrate that the abundant Te atomic clusters acting as active centers can drive the electron redistribution of carbonate via forming TeO bonds, giving rise to poor-crystalline Li2 CO3 film during the discharge process. Moreover, the efficient electron transfer between the Te centers and intermediate species is energetically beneficial for nucleation and accelerates the decomposition of Li2 CO3 on the TeAC @NCNS during the discharge/charge process.

Biaxially Compressive Strain in Ni/Ru Core/Shell Nanoplates Boosts Li-CO2 Batteries.

Regulating surface strain of nanomaterials is an effective strategy to manipulate the activity of catalysts, yet not well recognized in rechargeable Li-CO2 batteries. Herein, biaxially compressive strained nickel/ruthenium core/shell hexagonal nanoplates (Ni/Ru HNPs) with lattice compression of ≈5.1% and ≈3.2% in the Ru {10-10} and (0002) facets are developed as advanced catalysts for Li-CO2 batteries. It is demonstrated that tuning the electronic structure of Ru shell through biaxially compressive strain engineering can boost the kinetically sluggish CO2 reduction and evolution reactions, thus achieving a high-performance Li-CO2 battery with low charge platform/overpotential (3.75V/0.88V) and ultralong cycling life (120 cycles at 200mA g-1 with a fixed capacity of 1000 mAh g-1 ). Density functional theory calculations reveal that the biaxially compressive strain can downshift the d-band center of surface Ru atoms and thus weaken the binding of CO2 molecules, which is energetically beneficial for the nucleation and decomposition of Li2 CO3 crystals during the discharge and charge processes. This study confirms that strain engineering, though constructing a well-defined core/shell structure, is a promising strategy to improve the inherent catalytic activity of Ru-based materials in Li-CO2 batteries.

Boosting Li-CO2 battery performances by creating holey structure on CNT cathodes

Li-CO2 batteries have attracted more and more attention because of their high theoretical energy density and promising CO2 capture capacity. However, irreversible formation of Li2CO3 during discharging causes a high overpotential, short cycling life, and poor rate capability. To enable Li-CO2 batteries stable and rechargeable operation, the development of high-efficiency catalysts for CO2 reduction and Li2CO3 decomposition is highly desired. Herein, holey carbon nanotubes (CNTs) are developed as the cathode catalysts for the rechargeable Li-CO2 batteries. Benefiting from abundant defects for enhancing CO2 reduction/evolution reactions and holey structures for storing more discharge products, and combining advantage of high conductivity of CNTs for rapid electron transport, the as-prepared Li-CO2 batteries with holey CNTs exhibited a low overpotential of 1.18 V at 50 mA g−1. More importantly, the batteries delivered an ultrahigh discharge capacity of 17,500 mA h g−1 and long-time stability over 1500 h at 100 mA g−1. This study unlocks new avenues to develop high-efficiency cathode catalysts for high-performance metal-CO2 batteries and beyond.

Iridium-decorated carbon nanotubes as cathode catalysts for Li-CO2 batteries with a highly efficient direct Li2CO3 formation/decomposition capability

Rechargeable Li-CO2 batteries are regarded as the ideal application for the superior energy storage technology. However, they still limited by the lack of high efficiency electrocatalyst and limited understanding for the electrochemical reaction mechanism. In this work, we prepared the Ir-CNT composite by a rotation hydrothermal method, which remarkably promoted the reaction kinetics and enhanced the electrocatalytic performance of Li-CO2 batteries. The incorporation of Ir nanoparticles shows high activity enhancement for the adsorption of Li2CO3 species, which was confirmed by density functional theory (DFT) calculations. The Ir-CNT cathode exhibited an excellent ability to catalyze the formation and decomposition of Li2CO3 during cycling. Therefore, a large specific capacity of 10325.9 mAh g -1 and an excellent high rate cyclability with stably over 100 cycles were achieved. The three-dimensional Ir-CNT cathode could spontaneously advance the electrocatalytic activity of CO2 oxidation and precipitation to increase specific capacities and cycle life, significantly boosting the practical application of Li-CO2 batteries.

Cationic metal-organic framework derived ruthenium-copper nano-alloys in porous carbon to catalytically boost the cycle life of Li-CO2 batteries.

Rechargeable Li-CO2 batteries are an innovative energy storage technology with broad application prospects owing to their superb energy density and ability to capture the greenhouse gas CO2. However, they are still suffering from severe challenges in the formation and decomposition of electrochemically sluggish Li2CO3 discharge products, resulting in poor battery performance. Development of an efficient cathodic electrocatalyst has the potential to address these issues by catalytically boosting the conversion of Li2CO3. Herein, we have designed a Ru-Cu nanoalloy decorated porous carbon (Ru-Cu@NPC) material derived from an anion-exchanged cationic MOF, and it can serve as an efficient cathode electrocatalyst for Li-CO2 batteries. Benefitting from the uniform distribution of ultrafine Ru-Cu nanoalloys with high catalytic performance, Ru-Cu@NPC displays excellent CO2 reduction and evolution activities. Impressively, the Li-CO2 battery with the Ru-Cu@NPC catalyst exhibits a remarkably low potential gap of 0.93 V at 100 mA g-1 and a stable discharge/charge cycling performance of more than 400 cycles at a high current density of 400 mA g-1 within a limiting capacity of 1000 mA h g-1. The study provides an opportunity for the research of cationic MOF derived bimetallic catalysts in the Li-CO2 battery field.

Correction: A rechargeable Li–CO2 battery based on the preservation of dimethyl sulfoxide

Correction for ‘A rechargeable Li–CO2 battery based on the preservation of dimethyl sulfoxide’ by Zhenhua Lu et al., J. Mater. Chem. A, 2022, 10, 13821–13828, https://doi.org/10.1039/d2ta02586h.