Fluoridation routes,function mechanism and application of fluorinated/fluorine-doped nanocarbon-based materials for various batteries:A review

With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms,doping fluorine atoms in nanocarbon-based materials is considered an effective way to improve the performance of used battery.However,there is still a blank in the systematic review of the mechanism and research progress of fluorine-doped nanostructured carbon materials in various batteries.In this review,the synthetic routes of fluorinated/fluorine-doped nanocarbon-based(CF_x)materials under different fluorine sources and the function mechanism of CF_x in various batteries are reviewed in detail.Subsequently,judging from the dependence between the structure and electrochemical performance of nanocarbon sources,the progress of CF_x based on different dimensions(0D–3D)for primary battery applications is reviewed and the balance between energy density and power density is critically discussed.In addition,the roles of CF_x materials in secondary batteries and their current applications in recent years are summarized in detail to illustrate the effect of introducing F atoms.Finally,we envisage the prospect of CF_x materials and offer some insights and recommendations to facilitate the further exploration of CF_x materials for various high-performance battery applications.

Photoactive materials based on semiconducting nanocarbons——A challenge opening new possibilities for photocatalysis

This perspective paper introduces the concept that nanocarbons and related materials such as carbon dots are an interesting intrinsic photocatalytic semiconducting material, and not only a modifier of the existing(semiconducting) materials to prepare hybrid materials. The semiconducting properties of the nanocarbons, and the possibility to have the band gap within the visible-light region through defect band engineering, introduction of light heteroatoms and control/manipulation of the curvature or surface functionalization are discussed. These materials are conceptually different from the "classical" semiconducting photocatalysts, because semiconductor domains with tuneable characteristics are embedded in a conductive carbon matrix, with the presence of various functional groups(as C=O groups) enhancing charge separation by trapping electrons. These nanocarbons open a range of new possibilities for photocatalysis both for energetic and environmental applications. The use of nanocarbons as quantum dots and photoluminescent materials was also analysed.

A review of nanocarbons in energy electrocatalysis: Multifunctional substrates and highly active sites

Nanocarbons are of progressively increasing importance in energy electrocatalysis, including oxygen reduction, oxygen evolution, hydrogen evolution, CO_2 reduction, etc. Precious-metal-free or metal-free nanocarbon-based electrocatalysts have been revealed to potentially have effective activity and remarkable durability, which is promising to replace precious metals in some important energy technologies,such as fuel cells, metal–air batteries, and water splitting. In this review, rather than overviewing recent progress completely, we aim to give an in-depth digestion of present achievements, focusing on the different roles of nanocarbons and material design principles. The multifunctionalities of nanocarbon substrates(accelerating the electron and mass transport, regulating the incorporation of active components,manipulating electron structures, generating confinement effects, assembly into 3 D free-standing electrodes) and the intrinsic activity of nanocarbon catalysts(multi-heteroatom doping, hierarchical structure,topological defects) are discussed systematically, with perspectives on the further research in this rising research field. This review is inspiring for more insights and methodical research in mechanism understanding, material design, and device optimization, leading to a targeted and high-efficiency development of energy electrocatalysis.

Defect and Doping Co‑Engineered Non‑Metal Nanocarbon ORR Electrocatalyst

Exploring low-cost and earth-abundant oxygen reduction reaction(ORR)electrocatalyst is essential for fuel cells and metal–air batteries.Among them,non-metal nanocarbon with multiple advantages of low cost,abundance,high conductivity,good durability,and competitive activity has attracted intense interest in recent years.The enhanced ORR activities of the nanocarbons are normally thought to originate from heteroatom(e.g.,N,B,P,or S)doping or various induced defects.However,in practice,carbon-based materials usually contain both dopants and defects.In this regard,in terms of the co-engineering of heteroatom doping and defect inducing,we present an overview of recent advances in developing non-metal carbon-based electrocatalysts for the ORR.The characteristics,ORR performance,and the related mechanism of these functionalized nanocarbons by heteroatom doping,defect inducing,and in particular their synergistic promotion effect are emphatically analyzed and discussed.Finally,the current issues and perspectives in developing carbon-based electrocatalysts from both of heteroatom doping and defect engineering are proposed.This review will be beneficial for the rational design and manufacturing of highly efficient carbon-based materials for electrocatalysis.

Nanocarbons and their hybrids as catalysts for non-aqueous lithium–oxygen batteries

Rechargeable lithium-oxygen(Li–O_2) batteries have been considered as the most promising candidates for energy storage and conversion devices because of their ultra high energy density. Until now, the critical scientific challenges facing Li–O_2batteries are the absence of advanced electrode architectures and highly efficient electrocatalysts for both oxygen reduction reaction(ORR) and oxygen evolution reaction(OER), which seriously hinder the commercialization of this technology. In the last few years, a number of strategies have been devoted to exploring new catalysts with novel structures to enhance the battery performance. Among various of oxygen electrode catalysts, carbon-based materials have triggered tremendous attention as suitable cathode catalysts for Li–O_2batteries due to the reasonable structures and the balance of catalytic activity, durability and cost. In this review, we summarize the recent advances and basic understandings related to the carbon-based oxygen electrode catalytic materials, including nanostructured carbon materials(one-dimensional(1D) carbon nanotubes and carbon nanofibers, 2D graphene nanosheets, 3D hierarchical architectures and their doped structures), and metal/metal oxide-nanocarbon hybrid materials(nanocarbon supporting metal/metal oxide and nanocarbon encapsulating metal/metal oxide). Finally, several key points and research directions of the future design for highly efficient catalysts for practical Li–O_2batteries are proposed based on the fundamental understandings and achievements of this battery field.

Lymph node mapping in rabbit liver cancer with nanocarbon and methylene blue injecta

Objective:To discuss the value of lymph node mapping in rabbit liver cancer with nanocarbon and methylene blue injecta.Methods:Rabbit liver cancer model was established by transplanting VX2 cells with laparotomy in celiac planting method.Twenty Japan white rabbits were divided into two groups randomly.Each group had 10 rabbits.Lymph node mapping in (wo groups rabbit liver cancer were observed.Two groups rabbit liver cancer and local lymph nodes were removed.The number and location of local lymph nodes were recorded,and then the samples were obtained from both groups.Results:The lymph nodes dyed time was(100.50±29.92) s in nanocarbon group,and(11.20+4.18) s in methylene blue group with statistical significance between two groups(P=0.000).In the comparison of lymph node fading time,nanocarbon group was(2.22±0.74) h,methylene blue group was(1.63+0.54) h,nanocarbon group was longer than the methylene blue group,but without statistical significance(P=0.058).The accuracy was 87.5% (35/40) in methylene blue group,while,the nanocarbon group was 87.2%(34/39),with statistical significance(P=1.000).Conclusions:Experimental results show that application of nanocarbon injection and methylene blue injection during resection of liver cancer and local lymph nodes in rabbit liver cancer model has obvious tracer function in liver cancer and lymphatic drainage. It can reduce the complexity and risk of the operation,and avoid the blindness in the process of traditional lymph node dissection surgery.Besides,they can effectively reduce the number of residual lymph nodes after operation.It can achieve the lymph node dissection more thoroughly, promptly,easily and safely.

Nanocarbon-Enhanced 2D Photoelectrodes:A New Paradigm in Photoelectrochemical Water Splitting

Solar-driven photoelectrochemical(PEC)water splitting systems are highly promising for converting solar energy into clean and sustainable chemical energy.In such PEC systems,an integrated photoelectrode incorporates a light harvester for absorbing solar energy,an interlayer for transporting photogenerated charge carriers,and a co-catalyst for triggering redox reactions.Thus,understanding the correlations between the intrinsic structural properties and functions of the photoelectrodes is crucial.Here we critically examine various 2D layered photoanodes/photocathodes,including graphitic carbon nitrides,transition metal dichalcogenides,layered double hydroxides,layered bismuth oxyhalide nanosheets,and MXenes,combined with advanced nanocarbons(carbon dots,carbon nanotubes,graphene,and graphdiyne)as co-catalysts to assemble integrated photoelectrodes for oxygen evolution/hydrogen evolution reactions.The fundamental principles of PEC water splitting and physicochemical properties of photoelectrodes and the associated catalytic reactions are analyzed.Elaborate strategies for the assembly of 2D photoelectrodes with nanocarbons to enhance the PEC performances are introduced.The mechanisms of interplay of 2D photoelectrodes and nanocarbon co-catalysts are further discussed.The challenges and opportunities in the field are identified to guide future research for maximizing the conversion efficiency of PEC water splitting.

Plasma activation towards oxidized nanocarbons for efficient electrochemical synthesis of hydrogen peroxide

Oxidized nanocarbons(ONCs)have been regarded as efficient electrocatalysts for H2O2 production.However,wet chemical procedures involving large volumes of strong acid and long synthetic time are usually needed to obtain these ONCs.Herein,a plasma activation strategy is developed as a rapid and environmentally benign approach to obtain various ONCs,including oxidized multiwalled carbon nanotubes,single-walled carbon nanotube,graphene,and super P carbon black.After a few minutes of plasma activation,oxygen-containing functional groups and defects can be effectively introduced onto the surface of nanocarbons.Enhanced electrocatalytic activity and selectivity are demonstrated by the plasma-ONCs for H2O2 production.Taking oxidized multiwalled carbon nanotubes as an example,high selectivity(up to 95%)and activity(0.75 V at 1 mA cm^(−2))can be achieved in alkaline solution.Moreover,ex situ x-ray photoelectron spectroscopy and in situ Raman measurements reveal that C–O,C=O,edge defect,and sp2 basal planar defect are probably the active sites.

Primary amine coupling on nanocarbon catalysts: Reaction mechanism and kinetics via fluorescence probe analysis

Non-metallic nanocarbon materials catalyzed coupling reactions of primary amines to produce imine is an efficient,green and sustainable synthetic route,which has a wide application prospect in fine chemicals or pharmaceutical molecules.In the present study,we show firstly the relatively high catalytic activity of graphene oxide in the reaction of oxidative coupling of benzylamine(OCB),which is even comparable with typical metal-based catalysts,indicating the great potential of nanocarbon materials in this reaction system.More importantly,a novel twophoton fluorescence probe molecule(N-propyl-4-hydrazinyl-1,8-naphthalimide,NA)with special chemical structure of hydrazine functionality was synthesized.The probe NA could selectively react with aldehyde or ketone compounds,leading to the photoluminescence enhancement via inhibition of photo induced electron transfer(PET)process.The synthesized NA was applied as probe in carbon catalyzed OCB system to predict the existence of reaction intermediate benzaldehyde(BA),indicating the reaction pathway of oxidation-deamination-condensation in nanocarbon catalyzed OCB process.The proposed luminescence-probe strategy for revealing the kinetics and mechanism may also shed light in other reaction systems concerning the intermediates or products of ketones or aldehydes.

Electrocatalytic conversion of CO_2 to liquid fuels using nanocarbon-based electrodes

Recent advances on the use of nanocarbon-based electrodes for the electrocatalytic conversion of gaseous streams of CO2 to liquid fuels are discussed in this perspective paper. A novel gas-phase electrocatalytic cell, different from the typical electrochemical systems working in liquid phase, was developed. There are several advantages to work in gas phase, e.g. no need to recover the products from a liquid phase and no problems of CO2 solubility, etc. Operating under these conditions and using electrodes based on metal nanoparticles supported over carbon nanotube (CNT) type materials, long C-chain products (in particular isopropanol under optimized conditions, but also hydrocarbons up to C8-C9) were obtained from the reduction of CO2 . Pt-CNT are more stable and give in some cases a higher productivity, but Fe-CNT, particular using N-doped carbon nanotubes, give excellent properties and are preferable to noble-metal-based electrocatalysts for the lower cost. The control of the localization of metal particles at the inner or outer surface of CNT is an importact factor for the product distribution. The nature of the nanocarbon substrate also plays a relevant role in enhancing the productivity and tuning the selectivity towards long C-chain products. The electrodes for the electrocatalytic conversion of CO2 are part of a photoelectrocatalytic (PEC) solar cell concept, aimed to develop knowledge for the new generation artificial leaf-type solar cells which can use sunlight and water to convert CO2 to fuels and chemicals. The CO2 reduction to liquid fuels by solar energy is a good attempt to introduce renewables into the existing energy and chemical infrastructures, having a higher energy density and easier transport/storage than other competing solutions (i.e. H2 ).

赋能纳米碳提高原油采收率研究进展

赋能纳米碳由于高横纵比和两亲化结构,体现出表面活性剂、分子薄膜、胶体、液晶分子和聚合物的多面特性,在纳米化学提高原油采收率领域独具优势和应用潜力。调研总结了一维碳纳米管、二维石墨烯等纳米碳结构和性质的共性与特性,全面归纳了纳米碳的起源、制备方法与赋能路径;提出了油藏高温、高矿化度条件纳米碳的精细调控赋能策略,剖析了赋能纳米碳在水-油和水-岩石界面吸附和组装机制,多维度精细表征手段及信息化物理模拟方法。以水驱油藏波及系数和波及区内驱油效率均低的普遍性问题为导向,基于纳米的分子—粒子跨尺度特征和水-油-岩界面效应提炼了赋能纳米碳大幅扩大波及系数和提高驱油效率的协同耦合机制。最后,提出了赋能纳米碳提高原油采收率规模应用存在的问题和低碳、高效的发展路径。

Nanocarbon-based electrode materials applied for supercapacitors

As one of the promising energy storage and conversion systems,supercapacitors(SCs)are highly favored owing to their high power density and good service life.Among all the key components of supercapacitor devices,the design and investigation of electrode materials play an essential role in determining the whole electrochemical charge storage performance.Recently,nanocarbon-based materials(e.g.,graphene,carbon dots,graphene quantum dots,etc.)have been widely used as SC electrode materials because of their good physical structure and chemical properties,providing a new route to further improve the energy density and life span of SCs.Here,we review the latest progress of nanocarbon-based materials(including nanocarbon and nanocarbon-based composite materials)as electrode materials in SCs application.The recent progress of carbon dots,graphene,carbon nanotubes,and other nanocarbon materials electrodes is summarized,while the capacitance and energy density of the above nanocarbon electrodes still need to be improved.Then,the preparation and performance of nanocarbonbased composite electrodes comprising transition metal oxides,conductive polymer,and metal-organic framework derived porous carbon are reviewed.Finally,we outline major challenges and propose some ideas on building better nanocarbon-based SC electrodes.

MOF衍生碳基材料的电催化应用及其先进表征技术

鉴于对清洁和可持续能源的需求,来自金属有机框架(MOFs)的纳米炭衍生物正崭露头角,成为电催化能量转化的独特催化剂。这些MOF衍生的纳米炭材料不仅保持了MOFs组成可定制和结构多样性等优势,而且在热解过程中可有效防止金属纳米颗粒和金属氧化物的聚集。因此,它们提高了电催化效率,改善了电导率,并在燃料电池和金属-空气电池等绿色能源技术中发挥了关键作用。该综述以MOF衍生碳基材料的炭化机制为起点,随后深入探讨了固有炭缺陷、金属和非金属原子掺杂,并研究了这些材料的合成策略。此外,全面介绍了先进的表征技术,包括原位映射和原位光谱学。最后,对MOF衍生碳基材料作为电催化剂的研究前景提供了见解。该综述的主要目标是为当前MOF衍生碳基电催化剂的状况提供更清晰的视角,鼓励更高效电催化材料的发展。

Hierarchical,seamless,edge-rich nanocarbon hybrid foams for highly efficient electromagnetic-interference shielding

Lightweight,flexible,ultrahigh-performance electromagnetic-interfe rence(EMI)shielding materials are urgently required in the areas of aircraft/aerospace,portable and wearable electronics.Herein,1 D carbon nanotubes(CNT)and carbon nanofibers(CNF)with 2 D edge-rich graphene(ERG)are used to form a lightweight,flexible CNT-ERG-CNF hybrid foam.This foam was fabricated through a self-sacrificial templating chemical vapor deposition process,where nanocarbons bond through covalent bonding,forming a hierarchical 3 D hybridized carbon nanostructure.Multistage conductive networks and heterogeneous interfaces were constructed using edge-rich nanocarbons to increase the induced currents and interfacial polarization which makes great contributions to achieve high absorption electromagnetic shielding effectiveness(SEA).The CNT-ERG-CNF hybrid foam exhibits EMI shielding effectiveness(SE)exceeding55.4 dB in the X-band while the specific SE(SSE,SE divided by mass density)achieves 9200 dB cm^(3)g^(-1),which surpasses that of nearly all other carbon-based composite materials.Furthermore,the structural stability and durability of the flexible CNT-ERG-CNF hybrid foams is examined by measuring EMI SE after 10000 times cyclic bending.Remarkably,this work not only provides a new idea for preparing hierarchical carbon materials for a wide range of applications,but presents some fundamental insights for achieving higher absorption losses in EMI shielding materials.

Single Cu atom dispersed on S,N-codoped nanocarbon derived from shrimp shells for highly-efficient oxygen reduction reaction

Recently,Cu-based single-atom catalysts(SACs)have garnered increasing attention as substitutes for platinum-based catalysts in the oxygen reduction reaction(ORR).Therefore,a facile,economical,and efficient synthetic methodology for the preparation of a high-performance Cu-based SAC electrocatalyst for the ORR is extremely desired,but is also significantly challenging.In this study,we propose a ball-milling method to synthesize isolated metal SACs embedded in S,N-codoped nanocarbon(MNSDC,M=Cu,Fe,Co,Ni,Mn,Pt,and Pd).In particular,the Cu-NSDC SACs exhibit high electrochemical activity for the ORR with half-wave potential(E_(1/2))of 0.84 V(vs.reversible hydrogen electrode(RHE),20 mV higher than Pt/C)in alkaline electrolyte,excellent stability,and electrocatalytic selectivity.Density functional theory(DFT)calculations demonstrated that the desorption of OH*intermediates was the rate-determining step over Cu-NSDC.This study creates a pathway for high-performance ORR single atomic electrocatalysts for fuel cell applications and provides opportunities to convert biowaste materials into commercial opportunities.

Promoting electrochemical reduction of CO_(2) to ethanol by B/N-doped sp^(3)/sp^(2) nanocarbon electrode

Electrochemical reduction of CO_(2) to value-added chemicals holds promise for carbon utilization and renewable electricity storage.However,selective CO_(2) reduction to multi-carbon fuels remains a significant challenge.Here,we report that B/N-doped sp^(3)/sp^(2) hybridized nanocarbon(BNHC),consisting of ultra-small nanoparticles with a sp^(3) carbon core covered by a sp^(2) carbon shell,is an efficient electrocatalyst for electrochemical reduction of CO_(2) to ethanol at relatively low overpotentials.CO_(2) reduction occurs with a Faradaic efficiency of 58.8%-69.1% for ethanol and acetate production at -0.5∼-0.6 V(vs.RHE),among which 51.6%-56.0% is for ethanol.The high selectivity for ethanol is due to the integrated effect of sp^(3)/sp^(2) carbon and B/N doping.Both sp^(3) carbon and B/N doping contribute to enhanced ethanol production with sp^(2) carbon reducing the overpotential for CO_(2) reduction to ethanol.

Actuation and blocking force of stacked nanocarbon polymer actuators

We have developed stacked nanocarbon polymer actuators that are composed of several nanocarbon polymer actuator films using nonwoven fabric as insulation layers.The nonwoven fabric prepared through electrospinning methods has extremely-low-density structures,which do not significantly prevent the motions of each nanocarbon actuator layer.Therefore,stacking several thin nanocarbon polymer actuators using nonwoven fabric as insulation layers is expected to increase generated force without decreasing the displacement of a one-layer actuator.We have prepared stacked actuators with one,two,three,four,and seven layers using this method.The displacement and blocking force of these actuators are measured and compared with those of one-layer actuators of different thicknesses.Displacement is weakly dependent on the thickness of the actuator films of the stacked actuators.On the contrary,it decreases considerably as the thickness of the actuator film of the one-layer actuator increases.In both cases,blocking force is proportional to the thickness of actuator films.We have developed a stacked actuator model based on a trilayer actuator model and confirmed the experimental results using the model.

N-doped nanocarbon embedded in hierarchically porous metal-organic frameworks for highly efficient CO_(2) fixation

The rational integration of multi-functional components with metal–organic frameworks(MOFs) to form MOF-based catalysts can often afford enhanced catalytic activity for specific reactions. Herein, we propose a novel strategy for the synthesis of hierarchically porous MOFs(e.g., MIL-101)-encapsulated N-doped nanocarbon(CN@MIL) by controlled pyrolysis of ionic liquids@MIL-101 precursors(ILs@MIL). The obtained CN@MIL composites not only possess abundant enlarged mesopores,but also show multi-active sites without the sacrifice of their structure stability. The CN@MIL can efficiently facilitate the mass transfer of substrates, exhibiting excellent catalytic performance in the synthesis of cyclic carbonates from epoxides and CO_(2) under mild and co-catalyst-free conditions(i.e., 90 ℃ and ambient pressure of CO_(2)). Furthermore, the multi-active Lewis acid sites and nucleophilic sites(Br ions) as well as the strong affinity of catalysts toward CO_(2)also contribute to the excellent catalytic activity of the CN@MIL. This study might open a new avenue for the rational design of MOF-based composites by employing ILs@MOF as precursors for advanced heterogeneous catalysis.

婴幼儿乳糜腹手术治疗:附11例报道

目的总结并分享婴幼儿乳糜腹的手术经验。方法回顾性分析2013年9月—2022年7月收治的11例手术治疗的乳糜腹患儿的临床资料。男婴8例,女婴3例;就诊年龄1(0.033,2)个月;产前彩超发现4例,出生后出现腹胀、呕吐症状7例。于肠系膜根部发现漏孔5例,给予缝合结扎,其中传统剖腹探查3例,使用纳米炭术中定位2例;肠旋转不良4例,予行Ladd手术;术中探查未见明显漏孔2例,予腹腔引流。结果11例患儿经手术治疗后皆治愈。随访3~6个月,无复发病例。结论婴幼儿乳糜腹保守治疗疗效不佳者可予手术治疗。术中探查发现漏孔者,予结扎后预后好。术中使用纳米炭定位可缩短手术时间。先天性肠旋转不良也是婴幼儿乳糜腹常见的病因,应积极探查复位,术后恢复好。