Coulombic Efficiency Research Articles

Intrinsically Conductive and Cu-Functionalized Polymer-Composite Membranes as Gas Diffusion Electrodes for CO2 Electroreduction.

We introduced a new class of gas diffusion electrodes (GDEs) with adjustable pore morphology. We fabricated intrinsically conductive polymer-composite membranes containing carbon filler, enabling a pore structure variation through film casting cum phase separation protocols. We further selectively functionalized specific pore regions of the membranes with Cu by a NaBH4-facilitated coating strategy. The as-obtained GDEs can facilitate the electrochemical CO2 reduction reaction (CO2RR) at Cu active sites that are presented inside a defined and electrically conductive pore system. When employing them as free-standing cathodes in a CO2 flow electrolyzer, we achieved >70% Faradaic efficiencies for CO2RR products at up to 200 mA/cm2. We further demonstrated that deposition of a dense Cu layer on top of the membrane leads to obstruction of the underlying pore openings, inhibiting an excessive wetting of the pore pathways that transport gaseous CO2. However, the presentation of Cu inside the pore system of our novel membrane electrodes increased the C2H4/CO selectivity by a factor of up to 3 compared to Cu presented in the dense layer on top of the membrane. Additionally, we found that gaseous CO2 could still access Cu in macropores after wetting with electrolyte, while CO2RR was completely suppressed in wetted nm-scale pores.

Integrated Interfacial Modulation Strategy: Trace Sodium Hydroxyethyl Sulfonate Additive for Extended-Life Zn Anode Based on Anion Adsorption and Electrostatic Shield.

Aqueous zinc-ion batteries (AZIBs) are poised to play a pivotal part in meeting the growing demands for energy storage and powering portable electronics for their superior security, affordability, and environmentally friendly characteristics. However, the detrimental side reactions occurring at the zinc anode and the dendrite caused by uneven zinc plating/stripping have greatly compromised the cycling life of AZIBs, thereby impeding their practical prospects. In this study, the interfacial comodulation strategy was employed by combining the "electrostatic shielding" effect of cations with the characteristic adsorption of anions. Two molar ZnSO4 served as the matrix, and sodium hydroxyethyl sulfonate (SHES) was selected as a low-cost, nontoxic additive. Experimental results confirm that SHES and zinc anode exhibit robust interactions that lead to the formation of an electrostatic shield and a dynamic adsorption layer at the interface, thereby suppressing hydrogen evolution and corrosion. The combined "electrostatic shielding" effect of sodium ions and the robust characteristic adsorption of hydroxyethyl sulfonate anions serve to guide the directed three-dimensional (3D) diffusion of Zn2+, facilitating rapid, stable, and uniform deposition of zinc. Due to these effects, incorporating 0.2 M SHES as an additive extends the cycle life beyond 3600 h and enables a highly reversible process of deposition and stripping in symmetric cells. Additionally, the Zn-Cu half-cell exhibits reliable cycling for over 1400 cycles, achieving an average Coulombic efficiency of 99.6%. Moreover, the introduction of this additive substantially enhances the performance of Zn-MnO2 and Zn-NH4V4O10 full cells. This study demonstrates the practical feasibility of achieving anodes with high reversibility in AZIBs through the implementation of a strategy that involves anion adsorption at the interface, which holds paramount significance for the practical application of AZIBs.

A Versatile Redox-Active Electrolyte for Solid Fixation of Polyiodide and Dendrite-Free Operation in Sustainable Aqueous Zinc-Iodine Batteries.

Practical utilization of zinc-iodine (Zn-I2) batteries is hindered by significant challenges, primarily stemming from the polyiodide shuttle effect on the cathode and dendrite growth on the anode. Herein, a feasible redox-active electrolyte has been introduced with tetraethylammonium iodide as an additive that simultaneously addresses the above mentioned challenges via polyiodide solidification on the cathode and the electrostatic shielding effect on the anode. The tetraethylammonium (TEA+) captures water-soluble polyiodide intermediates (I3 -, I5 -), forming a solid complex at the cathode, thereby suppressing capacity loss during charge/discharge. Furthermore, the TEA+ mitigates dendrite growth on the Zn anode via the electrostatic shielding effect, promoting uniform and compact Zn deposition at the anode. Consequently, the Zn||Zn symmetric cell demonstrates superior cycling stability during Zn plating/stripping over 4,200h at 1mA cm-2 and 1 mAh cm-2. The Zn||NiNC full-cell exhibits a stable capacity retention of 98.4% after 20000 cycles (>5 months) with near-unity Coulombic efficiency at 1 A g-1. The study provides novel insights for establishing a new direction for low-cost, sustainable, and long-lifespan Zn-I2 batteries.

Electron-Efficient Co-electrosynthesis of Formates from CO2 and Methanol Feedstocks.

The electrochemical conversion of CO2 into valuable chemicals using renewable electricity shows significant promise for achieving carbon neutrality and providing alternative energy storage solutions. However, its practical application still faces significant challenges, including high energy consumption, poor selectivity, and limited stability. Here, we propose a hybrid acid/alkali electrolyzer that couples the acidic CO2 reduction reaction (CO2RR) at the cathode with alkaline methanol oxidation reaction (MOR) at the anode. This dual electro-synthesis cell is implemented by developing Bi nanosheets as cathode catalysts and oxide-decorated Cu2Se nanoflowers as anode catalysts, enabling high-efficiency electron utilization for formate production with over 180% coulombic efficiency and more than 90% selectivity for both CO2RR and MOR conversion. The hybrid acid/alkali CO2RR-MOR cell also demonstrates long-term stability exceeding 100 hours of continuous operation, delivers a formate partial current density of 130 mA cm-2 at a voltage of only 2.1 V, and significantly reduces electricity consumption compared to the traditional CO2 electrolysis system. This study illuminates an innovative electron-efficiency and energy-saving techniques for CO2 electrolysis, as well as the development of highly efficient electrocatalysts.

Electrosynthesis of Amides through Cu- and Co-Incorporated Nickel Hydroxide-Catalyzed Oxidation of Primary Amines Coupled with Hydrogen Evolution.

The electrocatalytic oxidation of organic molecules coupled with hydrogen evolution reaction can reduce overpotential and can be connected in series with nonelectrochemical processes to achieve the preparation of more high-value compounds. Herein, Cu- and Co-incorporated nickel hydroxide (CuCo-Ni(OH)2) was synthesized and applied to the anodic benzylamine oxidation reaction, which is 280 mV lower than the corresponding oxygen evolution reaction to reach the current density of 50 mA cm-2. When the electrocatalytic oxidation of benzylamine and hydrogen evolution reaction are coupled to form an electrolytic cell, the potential to reach 10 mA cm-2 is reduced by 197 mV compared to the overall water splitting. The benzylamine is converted to benzamide with 99.3% conversion and 90.2% faraday efficiency under 1.45 V constant voltage electrolysis, and the catalytic performance remains at a high level after 4 cycles. The characterization and density functional theory calculations show that Cu and Co share the transfer charge from Ni, making it easy for CuCo-Ni(OH)2 to deprotonate Ni-O* sites. The formed Ni-O* sites exhibit lower energy barriers in the proton transfer of benzylamine to benzonitrile and hydration intermediates, resulting in a better catalytic performance of CuCo-Ni(OH)2 than Ni(OH)2 in the electrocatalytic oxidation of benzylamine to benzamide.

Cascade Electrocatalytic Reduction of Nitrate to Ammonia Using a Heterobimetallic Covalent Organic Framework Composed of Cu-Porphyrin and Co-Bipyridine.

The electrocatalytic reduction of nitrate (NO3-) to ammonia (NH3) not only offers an effective solution to environmental problems caused by the accumulation of NO3- but also provides a sustainable alternative to the Haber-Bosch process. However, the conversion of NO3- to NH3 is a complicated process involving multiple steps, leading to a low Faradaic efficiency (FE) for NH3 production. The structural designability of covalent organic frameworks (COFs) renders feasible and precise modulation at the molecular level, facilitating the incorporation of multiple well-defined catalytic sites with different reactivities into a cohesive entity. This promotes the efficiency of the overall reaction through the coupling of multistep reactions. Herein, heterobimetallic CuP-CoBpy was prepared by postmodification, involving the anchoring of cobalt ions to the CuP-Bpy structure. As a result of the cascade effect of the bimetallic sites, CuP-CoBpy achieved an outstanding NH3 yield of 13.9 mg h-1 mgcat.-1 with a high FE of 96.7% at -0.70 V versus the reversible hydrogen electrode and exhibited excellent stability during catalysis. A series of experimental and theoretical studies revealed that the CuP unit facilitates the conversion of NO3- to NO2-, while the CoBpy moiety significantly prompts the reduction of NO2- to NH3. This study demonstrates that tailoring the structural units for the construction of COFs based on each step in the multistep reaction can enhance both the catalytic activity and product selectivity of the overall process.

Lewis-base ligand-reshaped interfacial hydrogen-bond network boosts CO2 electrolysis.

Both the catalyst and electrolyte strongly impact the performance of CO2 electrolysis. Despite substantial progress in catalysts, it remains highly challenging to tailor electrolyte compositions and understand their functions at the catalyst interface. Here, we report that the ethylenediaminetetraacetic acid (EDTA) and its analogs, featuring strong Lewis acid-base interaction with metal cations, are selected as electrolyte additives to reshape the catalyst-electrolyte interface for promoting CO2 electrolysis. Mechanistic studies reveal that EDTA molecules are dynamically assembled toward interface regions in response to bias potential due to strong Lewis acid-base interaction of EDTA4--K+. As a result, the original hydrogen-bond network among interfacial H2O is disrupted, and a hydrogen-bond gap layer at the electrified interface is established. The EDTA-reshaped K+ solvation structure promotes the protonation of *CO2 to *COOH and suppressing *H2O dissociation to *H, thereby boosting the co-electrolysis of CO2 and H2O toward carbon-based products. In particular, when 5mM of EDTA is added into the electrolytes, the Faradaic efficiency of CO on the commercial Ag nanoparticle catalyst is increased from 57.0% to 90.0% at an industry-relevant current density of 500mA cm-2. More importantly, the Lewis-base ligand-reshaped interface allows a range of catalysts (Ag, Zn, Pd, Bi, Sn, and Cu) to deliver substantially increased selectivity of carbon-based products in both H-type and flow-type electrolysis cells.

Porous Bi Nanosheets Derived from β-Bi2O3 for Efficient Electrocatalytic CO2 Reduction to Formate.

The electrochemical CO2 reduction reaction (ECO2RR) is a promising strategy for converting CO2 into high-value chemical products. However, the synthesis of effective and stable electrocatalysts capable of transforming CO2 into a specified product remains a huge challenge. Herein, we report a template-regulated strategy for the preparation of a Bi2O3-derived nanosheet catalyst with abundant porosity to achieve the expectantly efficient CO2-to-formate conversion. The resultant porous bismuth nanosheet (p-Bi) not only exhibited marked Faradaic efficiency of formate (FEformate), beyond 91% in a broad potential range from -0.75 to -1.1 V in the H-type cell, but also demonstrated an appreciable FEformate of 94% at a high current density of 262 mA cm-2 in the commercially important gas diffusion cell. State-of-the-art X-ray absorption near edge structure spectroscopy (XANES) and theoretical calculation unraveled the distinct formate production performance of the p-Bi catalyst, which was cocontributed by its smaller size, plentiful porous structure, and stronger Bi-O bond, thus accelerating the absorption of CO2 and promoting the subsequent formation of intermediates. This work provides an avenue to fabricate bismuth-based catalysts with high planar and porous morphologies for a broad portfolio of applications.

Preferred crystal plane electrodeposition of aluminum anode with high lattice-matching for long-life aluminum batteries

Aluminum batteries have become the most attractive next-generation energy storage battery due to their advantages of high safety, high abundance, and low cost. However, the dendrite problem associated with inhomogeneous electrodeposition during cycling leads to low Coulombic efficiency and rapid short-circuit failure of the aluminum metal anode, which severely hampers the cycling stability of aluminum battery. Here we show an aluminum anode material that achieves high lattice matching between the substrate and the deposit, allowing the aluminum deposits to maintain preferred crystal plane growth on the substrate surface. It not only reduces the nucleation barrier of aluminum and decreases electrode polarization, but also enables uniform deposition of aluminum, improving the cycling stability of aluminum batteries. Aluminum anode with (111) preferred crystal plane can stably 25000 cycles at the current density of 5 A·g−1, with a capacity retention rate of over 80%.

Conductive Zeolite Supported Indium-Tin Alloy Nanoclusters for Selective and Scalable Formic Acid Electrosynthesis.

Upgrading excess CO2 toward the electrosynthesis of formic acid is of significant research and commercial interest. However, simultaneously achieving high selectivity and industrially relevant current densities of CO2-to-formate conversion remains a grand challenge for practical implementations. Here, an electrically conductive zeolite support is strategically designed by implanting Sn ions into the skeleton structure of a zeolite Y, which impregnates ultrasmall In0.2Sn0.8 alloy nanoclusters into the supercages of the tailored 12-ring framework. The prominent electronic and geometric interactions between In0.2Sn0.8 nanoalloy and zeolite support lead to the delocalization of electron density that enhances orbital hybridizations between In active site and *OCHO intermediate. Thus, the energy barrier for the rate-limiting *OCHO formation step is reduced, facilitating the electrocatalytic hydrogenation of CO2 to formic acid. Accordingly, the developed zeolite electrocatalyst achieves an industrial-level partial current density of 322mA cm-2 and remarkable Faradaic efficiency of 98.2% for formate production and stably maintains Faradaic efficiency above 93% at an industrially relevant current density for over 102 h. This work opens up new opportunities of conductive zeolite-based electrocatalysts for industrial-level formic acid electrosynthesis from CO2 electrolysis and toward practically accessible electrocatalysis and energy conversion.

Molecular Electrochemical Catalysis of CO-to-Formaldehyde Conversion with a Cobalt Complex.

Formox, a highly energy-intensive process, currently serves as the primary source of formaldehyde (HCHO), for which there is a crucial and steadily growing chemical demand. The alternative electrochemical production of HCHO from C1 carbon sources such as CO2 and CO is still in its early stages, with even the few identified cases lacking mechanistic rationalization. In this study, we demonstrate that cobalt phthalocyanine (CoPc) immobilized on multiwalled carbon nanotubes (MW-CNTs) constitutes an excellent electrocatalytic system for producing HCHO with productivity through the direct reduction of CO, the two-electron reduction product of CO2. By carefully adjusting both the pH and the applied potential, we identified conditions that enable the production of HCHO with a partial current density of 0.64 mA cm-2 (17.5% Faradaic efficiency, FE) and a total FE of 61.2% for the liquid products (formaldehyde and methanol). A reduction mechanism is proposed.

Metal–Organic Framework Supported Low‐Nuclearity Cluster Catalysts for Highly Selective Carbon Dioxide Electroreduction to Ethanol

AbstractIt is still a great challenge to achieve high selectivity of ethanol in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials and lower energy barrier of possible other C2+ products. Here, we report a MOF‐based supported low‐nuclearity cluster catalysts (LNCCs), synthesized by electrochemical reduction of three‐dimensional (3D) microporous Cu‐based MOF, that achieves a single‐product Faradaic efficiency (FE) of 82.5 % at −1.0 V (versus the reversible hydrogen electrode) corresponding to the effective current density is 8.66 mA cm−2. By investigating the relationship between the species of reduction products and the types of catalytic sites, it is confirmed that the multi‐site synergism of Cu LNCCs can increase the C−C coupling effect, and thus achieve high FE of CO2–to–ethanol. In addition, density functional theory (DFT) calculation and operando attenuated total reflectance surface‐enhanced infrared absorption spectroscopy further confirmed the reaction path and mechanism of CO2–to–EtOH.

Unraveling the Active Sites on Mesoporous CuFe2O4@N-Carbon Catalysts with Abundant Oxygen Vacancies and M-N-C Content for Boosted Nitrogen Reduction Toward Electrosynthesis of Ammonia.

Transition metal centers dispersed over nitrogen-doped carbon (M-NC) supports have been widely explored for electrocatalytic reactions; however, sparsely reported for electrochemical nitrogen reduction reaction (ENRR). Particularly, the single-atom catalysts (SACs) have shown reasonable ammonia yield rate and faradaic efficiency (FE), but their complex synthesis and low durability for long-term electrocatalysis runs restrict their use on a larger scale. Importantly, the catalytic active sites in metal nanostructured-based M-NC catalysts toward enhanced N2 adsorption and activation are still not clear as they are highly challenging to reveal. A few studies have predicted that the surface oxygen vacancies (Ovac) favor an enhanced ENRR performance. Herein, a strategy using tailored M-NC content and Ovac in a single catalyst for enhanced ammonia electrosynthesis is devised. A mesoporous bimetallic spinel oxide (CuFe2O4) supported over N-doped carbon (CuFe2O4@NC) derived from Prussian blue analog (PBA) via controlled pyrolysis possess is found to show boosted ENRR activity. Moreover, operando NH3 formation over the catalyst is observed using four electrode set up. This approach enables rapid evaluation ofelectrocatalytic efficacy and avoids false positive results. The rotating disc electrode results reveal that mass transport in acidic media and surface absorption in alkline media primarily regulate ENRR over CuFe2O4@NC electrocatalyst.

Balancing pH for enhanced bacterial community performance in microbial fuel cells: implications for bio-electricity generation and pollutant reduction

Microbial fuel cells (MFCs) represent a promising technology to generate bio-electricity and synchronously reduce wastewater pollutants. The presence of exoelectrogens in wastewater is critical for bio-electricity and pollutant reduction, but the performance of exoelectrogens at different pH levels remains unknown. This study aims to bridge this gap by offering an integrated approach to understanding the performance of exoelectrogens under varying substrate pH, particularly in bio-electricity generation and pollutant reduction in sugarbeet processing wastewater (SBWW). Three pH levels (ranging from acidic to alkaline) were studied and MFC's electricity output was measured. Later, current density, power density, and coulombic efficiency (CE) were calculated. Both pre- and post-experiment substrate samples were analysed with inductively coupled plasma (ICP). Furthermore, 16S rRNA gene analysis, DNA amplification, sequencing library preparation, and bioinformatics workflows on post-experiment samples of the substrate and anode samples were conducted. A diverse community of microorganisms was identified, especially Alphaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria (Geobacter). Bacteroidetes and Desulfovibrio were the major exoelectrogens responsible for electricity generation. Among the three pH levels tested, the most alkaline pH level (9.5±0.1) outperformed the others, achieving a 54% higher power density, 21% greater current density, and a 40% higher CE compared to the acidic pH level (6.5±0.1). Around 50–99% of pollutants were removed from the SBWW. The study revealed that Gammaproteobacteria thrive and perform better in alkaline environment.

Application of artificial SEI layers for lithium metal battery anodes

Unpredictable lithium dendrite growth on the metal anode and repeated destruction and creation of the solid electrolyte interphase (SEI) layer result in hidden risks and low Coulombic efficiencies (CEs). Researchers have found that designing a high-quality SEI layer can prevent the growth of dendrite. However, designing and forming a high-quality SEI layer is still a problem. Making trade-off between capacity reduction caused by the SEI layer and better cycle stability significantly limits the general performance of lithium metal batteries. In this research, characteristics of SEI layers and some significant advancements made in SEI formation are outlined. Some designs for the SEI layers on the lithium metal anodes include designing hybrid polymer SEI layers, producing synthetic SEI layers. By controlling the behaviours of Li ions throughout the stripping and depositing processes, the capacity and stability of Li metal anodes may be improved. Finally, some case studies of the applying of SEI in lithium metal battery systems are introduced.

Added Anions to Zirconia as a Ceramic Material

Abstract: Anodic polarization of zircaloy-4 has been studied at a constant current density of 8 mA.cm2 and at room temperature. Thickness estimates were made from capacitance and faradaic data. Anodic polarized coloured zirconia film was observed by the addition of millimolar concentration of anions (Cl¯). By the addition of chloride ions to the oxalic acid dihydrate was better improvement in the anodization rate, faradaic efficiency field strength zirconia ceramic is recorded for exhibiting enhanced mechanical properties for manufacture of medical devices as well as biocompatability and have biological properties also. In future research needed to validate zirconia ceramic applications

Fabrication and characterization of Sb2O3-MoS2 nanocomposites for high performance supercapacitor applications.

Binary nanocomposite-based electrodes have been studied extensively in recent times owing to their multiple oxidation states, excellent physico-chemical features, and combined morphology, which are suitable for increasing the electrochemical performance of supercapacitors. The present work deals with Sb2O3-MoS2 NCs electrode for supercapacitor applications. The XRD, Raman, SEM, EDX, HRTEM, SAED and XPS characterizations have been studied to analyze the phase formation, vibrational modes, morphology, elemental composition and binding energies of the prepared Sb2O3-MoS2 NCs electrode material, as well as their electrochemical measurements such as CV, GCD, and EIS have been analyzed. The developed Sb2O3-MoS2 NCs electrode provides a high specific capacitance of 454.3 F/g at the current density of 1 A/g. Further, the hybrid supercapacitor device has been constructed which shows 104.04 F/g of specific capacitance at 2 A/g and manifests a good energy density of 24.42 Wh/kg at a power density of 1299.89 W/kg. Additionally, the hybrid device Sb2O3-MoS2//AC exhibits a good capacitive retention of 90.6% and a coulombic efficiency of 100.45% at 10 A/g over 8000 cycles.

Unveiling the impact of stabilization pretreatment on sodium storage performance in hard carbon

Stabilization pretreatment coupled with molecular cross-linking is commonly used to modify starch, aiming to obtain starch-based hard carbon materials with appropriate spherical particle sizes. Nevertheless, the impact of the intermediate stabilization process on its sodium storage performance remains unclear. Herein, a hard carbon material with no surface open pores, low specific surface area and abundant internal closed pores with thinner pore walls is successfully synthesized and exhibits significantly improved initial Coulombic efficiency and plateau capacity through a simple low-temperature pretreatment strategy, using renewable and cost-effective soluble starch as the raw material. Additionally, research indicates that an appropriate degree of disorder or defectiveness is conducive to forming a larger quantity of closed pores with thinner pore walls. Both excessively low and high defect levels are detrimental to the formation of closed pores. This work will encourage researchers to further focus on the impact of defectiveness on closed pores, which will promote the development of high-energy practical sodium-ion batteries.

Sodium Ion-Conducting Electrolytes Based on Chloroaluminate Ionic Liquids and δ-NaCl.

Sodium-containing ionic liquids are very promising candidates as ion-conducting materials in alternative to electrolytes based on lithium chemistry. Here we investigate a series of seven ionic liquids with formula (EMImCl/(AlCl3)1.5)/(δ-NaCl)x (0≤x≤0.74). The salt is comprised of a disordered form of NaCl prepared by metalorganic synthesis, which assures faster dissolution in high concentration. The vibrational investigation carried out by FT-IR spectroscopy in the medium IR region shed light on salt-IL interactions. The ionic conductivity was investigated by Broadband Electric Spectroscopy. The direct current conductivity (σdc) profiles versus the reciprocal temperature exhibited a Vogel-Tamman-Fulcher behavior indicating the assistance of micro-Brownian motions to ionic migration. The value of σdc at 25 °C for x=0.74 was found to be 1.2×10-2 S cm-1. Reversible deposition of Na and Al-containing species take place with high Coulombic efficiency (up to 97 %) and a high Na+ cation transport number (up to 0.95). The understanding of ionic speciation was investigated in comparison with aqueous acid-base systems exploring the benefits and limitations of such analogy. The role of a Grotthuss-type mechanism facilitating the exchange of chlorides between acidic catenated chloroaluminate species in anionic domains of the ILs is considered.

Gradient Lithium Ion Regulation Current Collectors for High-Performance and Dendrite-Free Li Metal Batteries.

Lithium metal anode has attracted wide attention due to its ultrahigh theoretical specific capacity, lowest reduction potential, and low density. However, uncontrollable dendritic growth and volume change caused by uneven Li+ deposition still seriously hinder the large-scale commercial application of lithium metal batteries, even causing serious battery explosions and other safety problems. Hence, gold nanoparticles with a gradient distribution anchored on 3D carbon fiber paper (CP) current collectors followed by the encapsulation of polydopamine (PDA) (CP/Au/PDA) are constructed for stable and dendrite-free Li metal anodes for the first time. Significantly, lithiophilic Au nanoparticles showing a gradient distribution in the carbon fiber paper could guide the transfer of Li+ from the outside to the inside of the CP/Au/PDA electrode as well as lower the nucleation overpotential of Li, thereby obtaining the uniform Li deposition. Meanwhile, the PDA layer could in situ be converted to Li-PDA which could serve as an efficient Li+ conductor to further facilitate uniform Li+ transport among the whole CP/Au/PDA electrode. Besides, 3D carbon fiber paper could effectively accommodate the volume change during the plating/stripping process of Li metal. As a result, CP/Au/PDA electrodes deliver a low nucleation overpotential (∼9 mV) and a high Coulombic efficiency (mean value of ∼98.8%) at a current density of 1 mA cm-2 with the capacity of 1 mA h cm-2. Furthermore, Li@CP/Au/PDA electrodes also can demonstrate an ultralow voltage hysteresis (∼20 mV) and a long cycle life (1000 h) in symmetric cells. Finally, with LiFePO4 (LFP) as the cathode, the Li@CP/Au/PDA-LFP full cell delivers a high discharge capacity of 136 mA h g-1 even after 350 cycles at 1C, exhibiting a per cycle loss as low as 0.01%. This gradient lithium ion regulation current collector is of great significance for the development of lithium metal anodes.