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1.
Small ; 20(25): e2310162, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38221703

RESUMO

Carbon sorbent materials have shown great promise for solid-state hydrogen (H2) storage. Modification of these materials with nitrogen (N) dopants has been undertaken to develop materials that can store H2 at ambient temperatures. In this work density functional theory (DFT) calculations are used to systematically probe the influence of curvature on the stability and activity of undoped and N-doped carbon materials toward H binding. Specifically, four models of carbon materials are used: graphene, [5,5] carbon nanotube, [5,5] D5d-C120, and C60, to extract and correlate the thermodynamic properties of active sites with varying degrees of sp2 hybridization (curvature). From the calculations and analysis, it is found that graphitic N-doping is thermodynamically favored on more pyramidal sites with increased curvature. In contrast, it is found that the hydrogen binding energy is weakly affected by curvature and is dominated by electronic effects induced by N-doping. These findings highlight the importance of modulating the heteroatom doping configuration and the lattice topology when developing materials for H2 storage.

2.
Small ; 20(28): e2310339, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38295011

RESUMO

The modulation of the coordination environment of single atom catalysts (SACs) plays a vital role in promoting CO2 reduction reaction (CO2RR). Herein, N or B doped Fe-embedded graphyne (Fe-GY), Fe-nXGYm (n = 1, 2, 3; X = N, B; m = 1, 2, 3), are employed as probes to reveal the effect of the coordination environment engineering on CO2RR performance via heteroatom doping in SACs. The results show that the doping position and number of N or B in Fe-GY significantly affects catalyst activity and CO2RR product selectivity. In comparison, Fe-1NGY exhibits high-performance CO2RR to CH4 with a low limiting potential of -0.17 V, and Fe-2NGY3 is demonstrated as an excellent CO2RR electrocatalyst for producing HCOOH with a low limiting potential of -0.16 V. With applied potential, Fe-GY, Fe-1NGY, and Fe-2NGY3 exhibit significant advantages in CO2RR to CH4 while hydrogen evolution reaction is inhibited. The intrinsic essence analysis illustrates that heteroatom doping modulates the electronic structure of active sites and regulates the adsorption strength of the intermediates, thereby rendering a favorable coordination environment for CO2RR. This work highlights Fe-nXGYm as outstanding SACs for CO2RR, and provides an in-depth insight into the intrinsic essence of the promotion effect from heteroatom doping.

3.
Small ; 20(14): e2308788, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988647

RESUMO

Heteroatom-doped porous carbon materials have investigated to promote the energy density of zinc-ion hybrid capacitors (ZICs). Yet, the quest for high-performance carbon materials or cathodes brings to light the question of which dopants facilitate fast energy storage kinetics and various types of pseudocapacitive reactions. Investigation of carbon materials with precise quantitative dopants as the key variable represents an effective appropriate approach to comprehending the intricate role of dopants in energy storage areas. Here, a straightforward solvothermal strategy is demonstrated for a variety of pristine and iron-incorporated polymer microspheres, used as precursors for durable spherical carbons intended for cathode applications in ZICs. The strategy effectively governs the incorporation of dopants within the carbon materials, whilewhile maintaining consistent morphology, microtexture, and pore structure across different carbon variations. The synergistic effect of various dopants enhance the pseudocapacitance and facilitate the ion storage process. In consequence, the optimal cathode delivers considerable capacity (178.8 mAh g-1 at 0.5 A g-1), good energy density (120.2 Wh kg-1 at 336 W kg-1), and excellent cycling stability (101.5% capacity retention at 35 000 cycles). The demonstration showcases a viable method for crafting carbon materials with precise dopants to accommodate the zinc anode, thus enabling high-capacity and high-energy ZICs.

4.
Small ; : e2403253, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860540

RESUMO

The electrochemical nitrate reduction reaction (NO3RR) is of significance in regards of environmentally friendly issues and green ammonia production. However, relatively low performance with a competitive hydrogen evolution reaction (HER) is a challenge to overcome for the NO3RR. In this study, oxygen vacancy-controlled copper oxide (CuOx) catalysts through a plasma treatment are successfully prepared and supported on high surface area porous carbon that are co-doped with N, Se species for its enhanced electrochemical properties. The oxygen vacancy-increased CuOx catalyst supported on the N,Se co-doped porous carbon (CuOx-H/NSePC) exhibited the highest NO3RR performance with faradaic efficiency (FE) of 87.2% and yield of 7.9 mg cm-2 h-1 for the ammonia production, representing significant enhancements of FE and ammonia yield as compared to the un-doped or the oxygen vacancy-decreased catalysts. This high performance should be attributed to a significant increase in the catalytic active sites with facilitated energetics from strategies of doping the catalytic materials and weakening the N─O bonding strength for the adsorption of NO3 - ions on the modulated oxygen vacancies. This results show a promise that co-doping of heteroatoms and regulating of oxygen vacancies can be key factors for performance enhancement, suggesting new guidelines for effective catalyst design of NO3RR.

5.
Small ; : e2311848, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556630

RESUMO

Designing biomimetic nanomaterials with peroxidase (POD)-like activity at neutral pH remains a significant challenge. An S-doping strategy is developed to afford an iron single-atom nanomaterial (Fe1@CN-S) with high POD-like activity under neutral conditions. To the best of knowledge, there is the first example on the achievement of excellent POD-like activity under neutral conditions by regulating the active site structure. S-doping not only promotes the dissociation of the N─H bond in 3,3″,5,5″-tetramethylbenzidine (TMB), but also facilitates the desorption of OH* by the transformation of iron species' spin states from middle-spin (MS FeII) to low-spin (LS FeII). Meanwhile, LS FeII sites typically have more unfilled d orbitals, thereby exhibiting stronger interactions with H2O2 than MS FeII, which can enhance POD-like activity. Finally, a one-pot visual detection of glucose at pH 7 is performed, demonstrating the best selectivity and sensitivity than previous reports.

6.
Small ; 20(1): e2304844, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37653594

RESUMO

Fabricating highly efficient and long-life redox bifunctional electrocatalysts is vital for oxygen-related renewable energy devices. To boost the bifunctional catalytic activity of Fe-N-C single-atom catalysts, it is imperative to fine-tune the coordination microenvironment of the Fe sites to optimize the adsorption/desorption energies of intermediates during oxygen reduction/evolution reactions (ORR/OER) and simultaneously avoid the aggregation of atomically dispersed metal sites. Herein, a strategy is developed for fabricating a free-standing electrocatalyst with atomically dispersed Fe sites (≈0.89 wt.%) supported on N, F, and S ternary-doped hollow carbon nanofibers (FeN4 -NFS-CNF). Both experimental and theoretical findings suggest that the incorporation of ternary heteroatoms modifies the charge distribution of Fe active centers and enhances defect density, thereby optimizing the bifunctional catalytic activities. The efficient regulation isolated Fe centers come from the dual confinement of zeolitic imidazole framework-8 (ZIF-8) and polymerized ionic liquid (PIL), while the precise formation of distinct hierarchical three-dimensional porous structure maximizes the exposure of low-doping Fe active sites and enriched heteroatoms. FeN4 -NFS-CNF achieves remarkable electrocatalytic activity with a high ORR half-wave potential (0.90 V) and a low OER overpotential (270 mV) in alkaline electrolyte, revealing the benefit of optimizing the microenvironment of low-doping iron single atoms in directing bifunctional catalytic activity.

7.
Small ; 20(27): e2310908, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38279585

RESUMO

The high potassization/depotassization energy barriers and lack of efficient ion diffusion pathways are two serious obstacles for carbon-based materials to achieve satisfactory potassium ion storage performance. Herein, a facile and controllable one-step exfoliation-doping-etching strategy is proposed to construct heteroatoms (N, O, and S)-doped mesoporous few-layer carbon nanosheets (NOS-C). The mixed molten salts of KCl/K2SO4 are innovatively used as the exfoliators, dopants, and etching agents, which enable NOS-C with expanded interlayer spacing and uniformly distributed mesopores with the adjusted electronic structure of surrounding carbon atoms, contributing efficient dual (vertical and horizontal) K-ion diffusion pathways, low potassization/depotassization energy barriers and abundant active sites. Thus, the NOS anodes achieve a high reversible capacity of 516.8 mAh g-1 at 0.05 A g-1, superior rate capability of 202.8 mAh g-1 at 5 A g-1 and excellent long-term cyclic stability, and their practical application potential is demonstrated by the assembled potassium-ion full batteries. Moreover, a surface-interlayer synergetic K+ storage mechanism is revealed by a combined theoretical and experimental approach including in situ EIS, in situ Raman, ex situ XPS, and SEM analysis. The proposed K+ storage mechanism and unique structural engineering provide a new pathway for potassium-ion storage devices and even beyond.

8.
Small ; 20(27): e2310250, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38295142

RESUMO

The commercialization of rechargeable Zn-air batteries (ZABs) relies on the material innovation to accelerate the sluggish oxygen electrocatalysis kinetics. Due to the differentiated mechanisms of reverse processes, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), rationally integrating dual sites for bifunctional oxygen electrocatalysis is prerequisite yet remains challenging. Herein, multicomponent synergistic active sites within highly graphitic carbon substrate are exquisitely constructed, which is accomplished by fluorine (F) modulation strategy. The incorporation of F dopants facilitates pyridinic N formation for anchoring single metal sites, thus guaranteeing the coexistence of sufficient M-Nx sites and metal nanoparticles toward bifunctional oxygen electrocatalysis. As a result, the optimal catalyst, denoted as F NH2-FeNi-800, outperforms commercial Pt/C+RuO2 with smaller gap between Ej = 10 and E1/2 (ΔE) of 0.63 V (vs 0.7 V for Pt/C+RuO2), demonstrating its superior bifunctionality. Beyond that, its superiority is validated in homemade rechargeable ZABs. ZABs assembled using F NH2-FeNi-800 as the air cathode delivers higher peak power density (123.8 mW cm-2) and long-cycle lifetime (over 660 cycles) in comparison with Pt/C@RuO2 (68.8 mW cm-2; 300 cycles). The finding not only affords a highly promising oxygen electrocatalyst, but also opens an avenue to constructing multifunctional active sites for heterogeneous catalysts.

9.
Small ; 20(26): e2309655, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38243851

RESUMO

Bifunctional catalysts have inherent advantages in simplifying electrolysis devices and reducing electrolysis costs. Developing efficient and stable bifunctional catalysts is of great significance for industrial hydrogen production. Herein, a bifunctional catalyst, composed of nitrogen and sulfur co-doped carbon-coated trinickel disulfide (Ni3S2)/molybdenum dioxide (MoO2) nanowires (NiMoS@NSC NWs), is developed for seawater electrolysis. The designed NiMoS@NSC exhibited high activity in alkaline electrolyte with only 52 and 191 mV overpotential to attain 10 mA cm-2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. Significantly, the electrolyzer (NiMoS@NSC||NiMoS@NSC) based on this bifunctional catalyst drove 100 mA cm-2 at only 1.71 V along with a robust stability over 100 h in alkaline seawater, which is superior to a platinum/nickel-iron layered double hydroxide couple (Pt||NiFe LDH). Theoretical calculations indicated that interfacial interactions between Ni3S2 and MoO2 rearranged the charge at interfaces and endowed Mo sites at the interfaces with Pt-like HER activity, while Ni sites on Ni3S2 surfaces at non-interfaces are the active centers for OER. Meanwhile, theoretical calculations and experimental results also demonstrated that interfacial interactions improved the electrical conductivity, boosting reaction kinetics for both HER and OER. This study presented a novel insight into the design of high-performance bifunctional electrocatalysts for seawater splitting.

10.
Chemistry ; 30(23): e202304157, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38270279

RESUMO

The environmental impact from the waste disposal has been widely concerned around the world. The conversion of wastes to useful resources is important for the sustainable society. As a typical family of wastes, biomass materials basically composed of collagen, protein and lignin are considered as useful resources for recycle and reuse. In recent years, the development of carbon material derived from biomasses, such as plants, crops, animals and their application in electrochemical energy storage have attracted extensive attention. Through the selection of the appropriate biomass, the optimization of the activation method and the control of the pyrolysis temperatures, carbon materials with desired features, such as high-specific surface area, variable porous framework, and controllable heteroatom-doping have been fabricated. Herein, this review summarized the preparation methods, morphologies, heteroatoms doping in the plant/animal-derived carbonaceous materials, and their application as electrode materials for secondary batteries and supercapacitors, and as electrode support for lithium-sulfur batteries. The challenges and prospects for the controllable synthesis and large-scale application of biomass-derived carbonaceous materials have also been outlooked.

11.
Chem Rec ; 24(1): e202300088, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37098879

RESUMO

CoP nanomaterials have been extensively regarded as one of the most promising electrocatalysts for overall water splitting due to their unique bifunctionality. Although the great promise for future applications, some important issues should also be addressed. Heteroatom doping has been widely acknowledged as a potential strategy for improving the electrocatalytic performance of CoP and narrowing the gap between experimental study and industrial applications. Recent years have witnessed the rapid development of heteroatom-doped CoP electrocatalysts for water splitting. Aiming to provide guidance for the future development of more effective CoP-based electrocatalysts, we herein organize a comprehensive review of this interesting field, with the special focus on the effects of heteroatom doping on the catalytic performance of CoP. Additionally, many heteroatom-doped CoP electrocatalysts for water splitting are also discussed, and the structure-activity relationship is also manifested. Finally, a systematic conclusion and outlook is well organized to provide direction for the future development of this interesting field.

12.
Nanotechnology ; 35(35)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729121

RESUMO

The massive volume dilation, unsteady solid electrolyte interphase, and weak conductivity about Si have failed to bring it to practical applications, although its potential capacity is up to 4200 mAh g-1. For solving these problems, novel binary regulated silicon-carbon materials (Si/BPC) were done by a sol-gel procedure combined with single carbonization. Analytical techniques were systematically utilized to examine the effects of element doping at several gradients on morphology, structure and electrochemical properties of composites, thus the optimal content was identified. Si/BPC preserves a discharge specific capacity of 1021.6 mAh g-1with a coulomb efficiency of 99.27% after 180 cycles at 1000 mA g-1, within the upgrade than single-doped and undoped. In rate test, it has a specific capacity of 1003.2 mAh g-1at a high current density of 5000 mA g-1, quickly back towards 2838.6 mAh g-1at 200 mA g-1. The inclusion of B and P elements is linked to the electrochemical characteristics. In the co-doped carbon layers, the synergistic impact of doping B and P accelerates the diffusion kinetics of lithium ions, boosts diffusion rate of Li+, offers low electrochemical impedance (45.75 Ω). This brings more defects to provide transport carriers and induces a substantial amount of electrochemically active sites, which fosters the storage of Li+, thus making silicon material electrochemically more active and potential.

13.
Nanotechnology ; 35(33)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38744256

RESUMO

Secondary battery as an efficient energy conversion device has been highly attractive for alleviating the energy crisis and environmental pollution. Hierarchical porous carbon (HPC) materials with multiple sizes pore channels are considered as promising materials for energy conversion and storage applications, due to their high specific surface area and excellent electrical conductivity. Although many reviews have reported on carbon materials for different fields, systematic summaries about HPC materials for lithium storage are still rare. In this review, we first summarize the main preparation methods of HPC materials, including hard template method, soft template method, and template-free method. The modification methods including porosity and morphology tuning, heteroatom doping, and multiphase composites are introduced systematically. Then, the recent advances in HPC materials on lithium storage are summarized. Finally, we outline the challenges and future perspectives for the application of HPC materials in lithium storage.

14.
Environ Res ; 251(Pt 1): 118595, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38462080

RESUMO

Over the last years, the strategy of employing inevitable organic waste and residue streams to produce valuable and greener materials for a wide range of applications has been proven an efficient and suitable approach. In this research, sulfur-doped porous biochar was produced through a single-step pyrolysis of birch waste tree in the presence of zinc chloride as chemical activator. The sulfur doping process led to a remarkable impact on the biochar structure. Moreover, it was shown that sulfur doping also had an important impact on sodium diclofenac (S-DCF) removal from aqueous solutions due to the introduction of S-functionalities on biochar surface. The adsorption experiments suggested that General and Liu models offered the best fit for the kinetic and equilibrium studies, respectively. The results showed that the kinetic was faster for the S-doped biochar while the maximum adsorption capacity values at 318 K were 564 mg g-1 (non-doped) and 693 mg g-1 (S-doped); highlighting the better affinity of S-doped biochar for the S-DCF molecule compared to non-doped biochar. The thermodynamic parameters (ΔH0, ΔS0, ΔG0) suggested that the S-DCF removal on both adsorbents was spontaneous, favourable, and endothermic.


Assuntos
Carvão Vegetal , Diclofenaco , Enxofre , Termodinâmica , Poluentes Químicos da Água , Diclofenaco/química , Cinética , Adsorção , Poluentes Químicos da Água/química , Enxofre/química , Carvão Vegetal/química , Purificação da Água/métodos , Porosidade
15.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731492

RESUMO

Carbon quantum dots are a novel form of carbon material. They offer numerous benefits including particle size adjustability, light resistance, ease of functionalization, low toxicity, excellent biocompatibility, and high-water solubility, as well as their easy accessibility of raw materials. Carbon quantum dots have been widely used in various fields. The preparation methods employed are predominantly top-down methods such as arc discharge, laser ablation, electrochemical and chemical oxidation, as well as bottom-up methods such as templates, microwave, and hydrothermal techniques. This article provides an overview of the properties, preparation methods, raw materials for preparation, and the heteroatom doping of carbon quantum dots, and it summarizes the applications in related fields, such as optoelectronics, bioimaging, drug delivery, cancer therapy, sensors, and environmental remediation. Finally, currently encountered issues of carbon quantum dots are presented. The latest research progress in synthesis and application, as well as the challenges outlined in this review, can help and encourage future research on carbon quantum dots.

16.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474582

RESUMO

Graphene quantum dots (GQDs) possess the photosensitive absorption for photoelectrochemical hydrogen evolution owing to special band structures, whereas they usually confront with photo-corrosion or undesired charge recombination during photoelectrochemical reactions. Hence, we establish the heterojunction between GQDs and MoSe2 sheets via a hydrothermal process for improved stability and performance. Photoanodic water splitting with hydrogen evolution boosted by the heteroatom doped N,S-GQDs/MoSe2 heterojunction has been attained due to the abundant active sites, promoted charge separation and transfer kinetics with reduced energy barriers. Diphasic 1T and 2H MoSe2 sheet-hybridized quantum dots contribute to the Schottky heterojunction, which can play a key role in expedited carrier transport to inhibit accumulative photo-corrosion and increase photocurrent. Heteroatom dopants lead to favored energy band matching, bandgap narrowing, stronger light absorption and high photocurrent density. The external quantum efficiency of the doped heterojunction has been elevated twofold over that of the non-doped pristine heterojunction. Modification of the graphene quantum dots and MoSe2 heterojunction demonstrate a viable and adaptable platform toward photoelectrochemical hydrogen evolution processes.

17.
Small ; 19(20): e2300440, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36808688

RESUMO

Nitrogen doping is an effective strategy to improve potassium ion storage of carbon electrodes via the creation of adsorption sites. However, various undesired defects are often uncontrollably generated during the doping process, limiting doping effect on capacity enhancement and deteriorating the electric conductivity. Herein, boron element is additionally introduced to construct 3D interconnected B, N co-doped carbon nanosheets to remedy these adverse effects. This work demonstrates that boron incorporation preferentially converts pyrrolic N species into BN sites with lower adsorption energy barrier, further enhancing the capacity of B, N co-doped carbon. Meanwhile, the electric conductivity is modulated via the conjugation effect between the electron-rich N and electron-deficient B, accelerating the charge-transfer kinetics of potassium ions. The optimized samples deliver a high specific capacity, high rate capability, and long-term cyclic stability (532.1 mAh g-1 at 0.05 A g-1 , 162.6 mAh g-1 at 2 A g-1 over 8000 cycles). Furthermore, hybrid capacitors using the B, N co-doped carbon anode deliver a high energy and power density with excellent cycle life. This study demonstrates a promising approach using BN sites for adsorptive capacity and electric conductivity enhancement in carbon materials for electrochemical energy storage applications.

18.
Small ; 19(52): e2305666, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635104

RESUMO

Tuning the coordination environment of the metal center in metal-nitrogen-carbon (M-N-C) single-atom catalysts via heteroatom-doping (oxygen, phosphorus, sulfur, etc.) is effective for promoting electrocatalytic CO2 reduction reaction (CO2 RR). However, few studies are investigated establishing efficient CO2 reduction by introducing boron (B) atoms to regulate the M-N-C structure. Herein, a B-C3 N4 self-sacrifice strategy is developed to synthesize B, N co-coordinated Ni single atom catalyst (Ni-BNC). X-ray absorption spectroscopy and high-angle annular dark field scanning transmission electron microscopy confirm the structure (Ni-N3 B/C). The Ni-BNC catalyst presents a maximum CO Faradaic efficiency (FECO ) of 98.8% and a large CO current density (jCO ) of -62.9 mA cm-2 at -0.75 and -1.05 V versus reversible hydrogen electrode, respectively. Furthermore, FECO could be maintained above 95% in a wide range of potential windows from -0.65 to -1.05 V. In situ experiments and density functional theory calculations demonstrate the Ni-BNC catalyst with B atoms coordinated to the central Ni atoms could significantly reduce the energy barrier for the conversion of *CO2 to *COOH, leading to excellent CO2 RR performance.

19.
Small ; 19(40): e2204119, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37259261

RESUMO

Heteroatom-doped porous carbon materials with distinctive surface properties and capacitive behavior have been accepted as promising candidates for supercapacitor electrodes. Currently, the researches mainly focus on developing facile synthetic method and unveiling the structure-activity relationship to further elevate their capacitive performance. Here, the B, N co-doped porous carbon sheet (BN-PCS) is constructed by one-pot pyrolysis of agar in KCl/KHCO3 molten salt system. In this process, the urea acts as directing agent to guide the formation of 2D sheet morphology, and the decomposition of KHCO3 and boric acid creates rich micro- and mesopores in the carbon framework. The specific capacitance of optimized BN-PCS reaches 361.1 F g-1 at a current density of 0.5 A g-1 in an aqueous KOH electrolyte. Impressively, the fabricated symmetrical supercapacitor affords a maximum energy density of 43.5 Wh kg-1 at the power density of 375.0 W kg-1 in 1.0 mol L-1 TEABF4 /AN electrolyte. It also achieves excellent long-term stability with capacitance retention of 91.1% and Columbic efficiency of 100% over 10 000 cycles. This study indicates one-pot molten salt method is effective in engineering advanced carbon materials for high-performance energy storage devices.

20.
Small ; 19(27): e2300605, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36974568

RESUMO

Hard carbons are deemed as promising anode materials for high-performance potassium-ion battery, but their commercialization is still hindered by the insufficient K+ transfer kinetics and poor potassiophilicity. Herein, these issues are addressed by improving the wettability of hard carbon, which can be achieved by the introduction of open mesochannels. A series of such hollow mesoporous carbon capsules with different dimensions are synthesized, which exhibit markedly enhanced wettability with electrolyte compared to the microporous counterparts. Various characterizations confirm its effects on promoting the kinetics and potassiophilicity of as-synthesized carbons, which can be additionally improved by S-doping. As a result, the 2D mesoporous carbon anode exhibits excellent rate capability (122.2 mAh g-1 at 4 A g-1 ), high reversible capacity (396.6 mAh g-1 at 0.1 A g-1 after 200 cycles), and outstanding cycling stability (197.0 mAh g-1 at 2 A g-1 after 1400 cycles). In addition, the hollow mesoporous architecture can effectively buffer the volume expansion and thus stabilize the carbon anodes, as visualized by in situ transmission electron microscopy. This work provides new insight for enhanced K+ storage performance from the perspective of anode wettability with electrolyte, as well as a universal anode design that combines mesochannels architecture with heteroatom doping.

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