Functional porous carbon-based composite electrode materials for lithium secondary batteries

The synthetic routes of porous carbons and the applications of the functional porous carbon-based composite electrode materials for lithium secondary batteries are reviewed. The synthetic methods have made great breakthroughs to control the pore size and volume, wall thickness, surface area, and connectivity of porous carbons, which result in the development of functional porous carbon-based composite electrode materials. The effects of porous carbons on the electrochemical properties are further discussed. The porous carbons as ideal matrixes to incorporate active materials make a great improvement on the electrochemical properties because of high surface area and pore volume, excellent electronic conductivity, and strong adsorption capacity. Large numbers of the composite electrode materials have been used for the devices of electrochemical energy conversion and storage, such as lithium-ion batteries （LIBs）, Li-S batteries, and Li-O2 batteries. It is believed that functional porous carbon-based composite electrode materials will continuously contribute to the field of lithium secondary batteries.

Directional Oxygen Functionalization by Defect in Different Metamorphic-Grade Coal-Derived Carbon Materials for Sodium Storage

As the limiting factor for an energy storage technique from lab-scale to industrial-scale,cost means not only the price of raw materials but also the simplicity of processing technics.In this work,the oxygen functionalized carbon materials were obtained from three representative different metamorphic-grade coals,that is,lignite,bitumite,anthracite.Oxygen functional groups like quinones,carboxylic anhydrides,and lactones are easier to form near defects according to the thermogravimetric-mass spectrometry measurements and density functional theory calculation.Considering the highest amount of defects and C=O contained functional groups,the low metamorphic-grade lignite derived carbon exhibits a reversible capacity of 259.7 mA h g^(-1)after 50 cycles at 0.03 A g^(-1),best among these micron sized coal-based carbons.The surface active sites contribute highly stable and majority of sodium storage capacity evidenced by in situ Raman spectra and cyclic voltammetry curves at different scan rates.The coal-based carbon materials in this work offer options for industrial applications of sodium-ion battery anode materials.

Proof of Aerobically Autoxidized Self-Charge Concept Based on Single Catechol-Enriched Carbon Cathode Material

The self-charging concept has drawn considerable attention due to its excellent ability to achieve environmental energy harvesting,conversion and storage without an external power supply.However,most self-charging designs assembled by multiple energy harvesting,conversion and storage materials increase the energy transfer loss;the environmental energy supply is generally limited by climate and meteorological conditions,hindering the potential application of these selfpowered devices to be available at all times.Based on aerobic autoxidation of catechol,which is similar to the electrochemical oxidation of the catechol groups on the carbon materials under an electrical charge,we proposed an air-breathing chemical self-charge concept based on the aerobic autoxidation of catechol groups on oxygen-enriched carbon materials to ortho-quinone groups.Energy harvesting,conversion and storage functions could be integrated on a single carbon material to avoid the energy transfer loss among the different materials.Moreover,the assembled Cu/oxygen-enriched carbon battery confirmed the feasibility of the air-oxidation self-charging/electrical discharging mechanism for potential applications.This air-breathing chemical self-charge concept could facilitate the exploration of high-efficiency sustainable air self-charging devices.

Nonlinear stability of advanced sandwich cylindrical shells comprising porous functionally graded material and carbon nanotube reinforced composite layers under elevated temperature

The nonlinear stability of sandwich cylindrical shells comprising porous functionally graded material(FGM) and carbon nanotube reinforced composite(CNTRC)layers subjected to uniform temperature rise is investigated. Two sandwich models corresponding to CNTRC and FGM face sheets are proposed. Carbon nanotubes(CNTs) in the CNTRC layer are embedded into a matrix according to functionally graded distributions. The effects of porosity in the FGM and the temperature dependence of properties of all constituent materials are considered. The effective properties of the porous FGM and CNTRC are determined by using the modified and extended versions of a linear mixture rule, respectively. The basic equations governing the stability problem of thin sandwich cylindrical shells are established within the framework of the Donnell shell theory including the von K’arm’an-Donnell nonlinearity. These equations are solved by using the multi-term analytical solutions and the Galerkin method for simply supported shells.The critical buckling temperatures and postbuckling paths are determined through an iteration procedure. The study reveals that the sandwich shell model with a CNTRC core layer and relatively thin porous FGM face sheets can have the best capacity of thermal load carrying. In addition, unlike the cases of mechanical loads, porosities have beneficial effects on the nonlinear stability of sandwich shells under the thermal load. It is suggested that an appropriate combination of advantages of FGM and CNTRC can result in optimal efficiency for advanced sandwich structures.

Electrospinning-derived functional carbon-based materials for energy conversion and storage

The over-exploitation of fossil fuel energy has brought about serious environmental problems.It would be of great significance to construct efficient energy conversion and storage system to maximize utilize renewable energy,which contributes to reducing environmental hazards.For the past few years,in terms of electrocatalysis and energy storage,carbon fiber materials show great advantages due to its outstanding electrical conductivity,good flexibility and mechanical property.As a simple and low-cost technique,electrospinning can be employed to prepare various nanofibers.It is noted that the functional fiber materials with different special structure and composition can be obtained for energy conversion and storage by combining electrospinning with other post-processing.In this paper,the structural design,controllable synthesis and multifunctional applications of electrospinning-derived functional carbon-based materials(EFCMs)is reviewed.Firstly,we briefly introduce the history,basic principle and typical equipment of electrospinning.Then we discuss the strategies for preparing EFCMs with different structures and composition in detail.In addition,we show recently the application of advanced EFCMs in energy conversion and storage,such as nitrogen species reduction reaction,CO_(2) reduction reaction,oxygen reduction reaction,water-splitting,supercapacitors and ion batteries.In the end,we propose some perspectives on the future development direction of EFCMs.

An All‑In‑One Multifunctional Touch Sensor with Carbon‑Based Gradient Resistance Elements

Human–machine interactions using deep-learning methods are important in the research of virtual reality,augmented reality,and metaverse.Such research remains challenging as current interactive sensing interfaces for single-point or multipoint touch input are trapped by massive crossover electrodes,signal crosstalk,propagation delay,and demanding configuration requirements.Here,an all-inone multipoint touch sensor(AIOM touch sensor)with only two electrodes is reported.The AIOM touch sensor is efficiently constructed by gradient resistance elements,which can highly adapt to diverse application-dependent configurations.Combined with deep learning method,the AIOM touch sensor can be utilized to recognize,learn,and memorize human–machine interactions.A biometric verification system is built based on the AIOM touch sensor,which achieves a high identification accuracy of over 98%and offers a promising hybrid cyber security against password leaking.Diversiform human–machine interactions,including freely playing piano music and programmatically controlling a drone,demonstrate the high stability,rapid response time,and excellent spatiotemporally dynamic resolution of the AIOM touch sensor,which will promote significant development of interactive sensing interfaces between fingertips and virtual objects.

Synergistic interaction between redox-active electrolytes and functionalized carbon in increasing the performance of electric double-layer capacitors

The increasing demand of high-performance supercapacitors has aroused great interest in developing specific capacitance and energy density. Active carbon （AC） has attracted much attention as a promising electrode material for electric double-layer capacitors （EDLCs）. Here, a facile strategy has been employed to fabricate high-performance EDLCs using the surface-oxygen functionalized active carbon （FAC） as an electrode and 2 M KOH with K3Fe（CN）6 as an electrolyte. In this system, K3Fe（CN）6 was used as a redox additive to enhance the performance of EDLCs. A 38.5% increase in specific capacitance （207.7 F g-1） was achieved compared with the KOH electrolyte without adding K3Fe（CN）G （152.9 F g-1）, due to the synergistic effects between oxygenic functional groups and redox electrolyte. These findings provide an alternative route to improve the performance of EDLCs, which are promising candidates for the broad applications of high-performance supercapacitors.

Vibration characteristics of piezoelectric functionally graded carbon nanotube-reinforced composite doubly-curved shells

This paper presents an analytical solution for the free vibration behavior of functionally graded carbon nanotube-reinforced composite(FG-CNTRC) doubly curved shallow shells with integrated piezoelectric layers. Here, the linear distribution of electric potential across the thickness of the piezoelectric layer and five different types of carbon nanotube(CNT) distributions through the thickness direction are considered. Based on the four-variable shear deformation refined shell theory, governing equations are obtained by applying Hamilton's principle. Navier's solution for the shell panels with the simply supported boundary condition at all four edges is derived. Several numerical examples validate the accuracy of the presented solution. New parametric studies regarding the effects of different material properties, shell geometric parameters, and electrical boundary conditions on the free vibration responses of the hybrid panels are investigated and discussed in detail.

Transition‐metal‐atom‐pairs deposited on g‐CN monolayer for nitrogen reduction reaction:Density functional theory calculations

The development of highly active DFT catalysts for an electrocatalytic N_(2)reduction reaction(NRR)under mild conditions is a difficult challenge.In this study,a series of atom‐pair catalysts(APCs)for an NRR were fabricated using transition‐metal(TM)atoms(TM=Sc−Zn)doped into g‐CN monolayers.The electrochemical mechanism of APCs for an NRR has been reported by well‐defined density functional theory calculations.The calculated limiting potentials were−0.47 and−0.78 V for the Fe_(2)@CN and Co_(2)@CN catalysts,respectively.Owing to its high suppression of hydrogen evolution reactions,Co_(2)@CN is a superior electrocatalytic material for a N_(2)fixation.Stable Fe_(2)@CN may be a strongly attractive material for an NRR with a relatively low overpotential after an improvement in the selectivity.The two‐way charge transfer affirmed the donation‐acceptance procedure between N_(2)and Fe_(2)@CN or Co_(2)@CN,which play a crucial role in the activation of inert N≡N bonds.This study provides an in‐depth investigation into atom‐pair catalysts and will open up new avenues for highly efficient g‐CN‐based nanostructures for an NRR.

Direct transformation of fossil carbon into chemicals: A review

Despite the long tradition of fossil carbon(coal,char,and related carbon-based materials)for fueling mankind,the science of transforming them into chemicals is still demandingly progressing in the current energy scenario,especially when considering its responsibilities to the global climate change.Traditionally,there are four routes of preparing chemicals directly from fossil carbon,including hydrogasification,gasification,direct liquefaction,and oxidation,in the macroscope of gas-solid reaction(hydrogasification and gasification)and liquid-solid reaction(direct liquefaction and oxidation).When the study goes to microscale,the gas-solid reaction can be considered as the reaction between the severe condensed radicals and gas,while the liquid-solid reaction is the direct reaction between the radical and the activated-molecule.To have a full overview of the area,this review systematically summarizes the main factors in these processes and shows our own perspectives as follows,(ⅰ)stabilizing the free radicals generated from coal and then directly converting them has the highest efficiency in coal utilization;(ⅱ)the research on the self-catalytic process of coal structure will have a profound impact on the direct preparation of chemicals from fossil carbon.Further discussions are also proposed to guide the future study of the area into a more sustainable direction.

Towards Practical Application of Li-S Battery with High Sulfur Loading and Lean Electrolyte:Will Carbon-Based Hosts Win This Race?

As the need for high-energy–density batteries continues to grow, lithium-sulfur(Li–S) batteries have become a highly promising next-generation energy solution due to their low cost and exceptional energy density compared to commercially available Li-ion batteries. Research into carbon-based sulfur hosts for Li–S batteries has been ongoing for over two decades, leading to a significant number of publications and patents.However, the commercialization of Li–S batteries has yet to be realized. This can be attributed, in part, to the instability of the Li metal anode. However, even when considering just the cathode side, there is still no consensus on whether carbon-based hosts will prove to be the best sulfur hosts for the industrialization of Li–S batteries. Recently, there has been controversy surrounding the use of carbon-based materials as the ideal sulfur hosts for practical applications of Li–S batteries under high sulfur loading and lean electrolyte conditions. To address this question, it is important to review the results of research into carbon-based hosts, assess their strengths and weaknesses, and provide a clear perspective. This review systematically evaluates the merits and mechanisms of various strategies for developing carbon-based host materials for high sulfur loading and lean electrolyte conditions. The review covers structural design and functional optimization strategies in detail, providing a comprehensive understanding of the development of sulfur hosts. The review also describes the use of efficient machine learning methods for investigating Li–S batteries. Finally, the outlook section lists and discusses current trends, challenges, and uncertainties surrounding carbon-based hosts, and concludes by presenting our standpoint and perspective on the subject.

酸皮基磷光型碳点的制备及防伪应用

以浸酸山羊皮为碳源、硼酸为硼源,采用热解法制备了磷光型碳点(P-CDs)。探讨了浸酸山羊皮含量、反应pH、反应温度和反应时间对P-CDs余辉时间的影响。采用有机元素分析仪、SEM、EDS、TEM、FTIR、XRD对样品进行了表征,并评价了P-CDs的防伪应用。结果表明,在浸酸山羊皮含量(以3 g硼酸为基准,下同)4.10%、反应pH为7、反应温度为225℃、反应时间为7.5 h的条件下,制备的P-CDs的余辉时间达到12s;该材料的最佳发射波长为520 nm,对应明亮的青绿色余辉。P-CDs平均粒径为4.42 nm,具有典型的石墨结构,硼原子成功地掺入到碳点中,形成了C—B、B—O等共轭链结构,稳定了三重激发态,延长了余辉时间。

Functional carbon materials addressing dendrite problems in metal batteries:surface chemistry,multi-dimensional structure engineering,and defects

Metal batteries that directly use active metals as anodes are considered as one of the most promising solutions to achieve the energy upgrade of battery technologies,while their practical application still suffers from dendrite problems.Functional carbon materials(FCMs)have demonstrated their great potential in suppressing metal dendrites benefitting from the multiple merits such as chemical tunability and capability of multi-dimensional structure assembly.Here,we initiate a review to present the recent progress in employing FCMs to deal with dendrite problems.It focuses on the surface chemistry and multi-dimensional carbon material engineering,which systematically overcomes the problems through diverse methods,such as reinforcing desolvation,improving interface compatibility,homogenizing electric field,buffering volume expansion and lattice mismatch.In addition,we also refine the long-standing debate about whether surface defects in FCMs are beneficial to suppress the metal dendrites or not,especially in the non-aqueous electrolyte regime.Finally,the remaining challenges for utilizing FCMs to suppress metal dendrites and the possible solutions are proposed to guide the future development.

电子功能材料生产过程节能技术规范金属材料标准分析

为响应国家绿色低碳要求,支撑金属功能材料行业发展,钢铁研究总院牵头制定《电子功能材料生产过程节能技术规范 第1部分:金属材料》,介绍了该标准制定的背景,重点分析了本次标准制订的术语定义、产品分类、考核评价要求等内容,结合产品应用及产业现状,提出相关建议,从而有效指导行业使用该标准,推动行业技术进步,提高行业的高质量发展水平。

生物质碳基催化材料的研究进展

生物质是产量丰富、种类繁多、价格低廉、环境友好的优良碳源,以生物质为原料制备碳催化材料无疑是变废为宝,可从根本上解决环境污染和资源浪费等问题。介绍了生物质的种类、组分及结构对生物质碳基催化材料性能的影响,对制备生物质碳基催化材料的两种常见方法热解法和水热碳化法进行了对比,探讨了进一步增强催化剂活性的3种方式:杂原子掺杂、金属离子修饰和官能化,分析总结了生物质碳催化材料面临的挑战。

CO_(2)基聚氨酯丙烯酸酯紫外光固化树脂的制备及性能

以CO_(2)基聚碳酸亚丙酯二醇(PPCD)为软段、二环己基甲烷二异氰酸酯(HMDI)为硬段、甲基丙烯酸羟丙酯(HPMA)为封端剂和稀释剂、2,4,6-三甲基苯甲酰基-二甲苯基氧化膦(TMO)为光引发剂,以不同氰羟比(HMDI中异氰酸酯基与PPCD中羟基的物质的量之比,下同)制备了一系列CO_(2)基聚氨酯丙烯酸酯(PUA)紫外光固化树脂,并经紫外光引发制备了PUA紫外光固化胶膜。通过FTIR、XRD表征和力学性能、TGA、黏度测试,考察了氰羟比对PUA紫外光固化树脂和胶膜结构与性能的影响。结果表明,随着氰羟比的增大,PUA紫外光固化胶膜的水接触角、硬度和拉伸强度增大,吸水率和断裂伸长率下降,PUA紫外光固化树脂黏度降低。以氰羟比为2.0∶1制备的PUA紫外光固化树脂(PUA-4树脂)和PUA紫外光固化胶膜(PUA-4胶膜)综合性能最好,PUA-4树脂黏度为1437 mPa·s;PUA-4胶膜拉伸强度为32.9 MPa,断裂伸长率为139.2%,水接触角为86.9°,24 h吸水率为8.2%,邵氏硬度为94 HA。

光热光动力协同抗菌碳点的制备、表征及性能

以烯丙基三甲基氯化铵(QAC)为碳源、CuCl_(2)·2H_(2)O为Cu掺杂原料,采用一步水热法合成了具有光热光动力协同抗菌性能的铜离子掺杂碳点(CuQACDs)。通过TEM、Zeta电位、FTIR、XPS、Raman光谱、UV-Vis吸收光谱对CuQACDs进行了结构表征。选用大肠杆菌(E.coli)及金黄色葡萄球菌(S.aureus)评价了CuQACDs的抗菌性能。结果表明,n(QAC)∶n(Cu^(2+))=1∶2制备的CuQACD2是具有良好分散性的球形纳米颗粒,平均水合粒径约为4.9 nm,Zeta电位为8.17 mV;在功率密度1.5 W/cm^(2)的808 nm激光照射下,CuQACD2光热转换效率为21.7%,同时可在细菌细胞内显著生成活性氧(ROS);CuQACD2对E.coli和S.aureus均有显著抑制效果,在质量浓度1.50 g/L下,采用功率密度1.5 W/cm^(2)的808 nm激光照射10 min后,E.coli的细胞存活率为1.67%,S.aureus的细胞存活率为1.06%。

MOFs负载ACF吸附剂的制备及H_(2)S脱除特性

将活性炭纤维(ACF)负载到金属有机框架材料MOF-199上,在水热条件下制备了MOF-199@ACF吸附剂,利用固定床反应装置评价其脱H_(2)S性能;采用氮气吸/脱附、XRD、EDS、SEM、XPS表征和分析了MOF-199@ACF的物相组成;考察了ACF负载量、吸附温度、相对湿度对MOF-199@ACF脱除H_(2)S性能的影响,探究了MOF-199@ACF在H_(2)S脱除中可能的反应机理。结果表明,与MOF-199相比,ACF负载量(质量分数)为1%的吸附剂MOF-199@1%ACF的H_(2)S出现时间从180 min延后至405 min,穿透硫容从7.2 mg/g提升至14.5 mg/g;ACF负载量为1%不会干扰MOF-199结晶形成的稳定结构,ACF参与配位使MOF-199@1%ACF表面粗糙化,导致更多的吸附位点暴露,增加了比表面积(从MOF-199的1108.6 m^(2)/g增至1978.3 m^(2)/g);MOF-199@1%ACF是以化学吸附的活化吸附为主,升高温度(30~70℃)有利于加快吸附速率;适量水气(相对湿度10%)有助于性能提升(穿透硫容14.8 mg/g)。

溶剂热法制备尼龙66基碳点及其指纹识别、荧光防伪、光线阻挡应用

以尼龙66(PA66)和植酸(IP6)为前驱体、乙酸为溶剂,采用溶剂热法制备了PA66基碳点(66CDs)。利用TEM、FTIR、XPS、荧光光谱对其进行了表征,对其光学性能、离子稳定性和时间稳定性进行了测试,探究了其指纹识别、荧光防伪、光线阻挡的应用。结果表明,将1.6 g PA66、1.1 g IP6加入20 mL乙酸中,于260℃下反应36h,制备的66CDs具有最大荧光强度。66CDs为球形结构,平均粒径4.00nm,表面含有羧基、羟基、氨基等官能团;66CDs的荧光为非激发波长依赖型,最佳激发波长和发射波长分别为360和490 nm,荧光量子产率可达11.69%,其荧光强度不受常见金属阳离子影响,30 d内具有稳定性。由66CDs与水溶性淀粉制备的荧光粉末可用于指纹识别,不仅可将66CDs制成油墨用于荧光防伪,还可将其制成防蓝光膜,用于蓝光防护。

碱金属修饰的萘炔/萘二炔对CO_(2)选择性吸附分离的理论计算

采用巨正则蒙特卡洛模拟和密度泛函理论结合的方式探究了不同碱金属(alkali metal,AM,包括Li、Na、K)修饰提升萘炔(naphyne,NY)和萘二炔(naphdiyne,NDY)的CO_(2)吸附分离性能。通过结合能和结构的电子性质分析发现,AM修饰的NY和NDY具有良好的结构稳定性。在298 K、100 k Pa的条件下,Li修饰的萘二炔(Li-NDY)表现出高达11.37 mmol·g^(-1)的CO_(2)吸附量和430.85的CO_(2)选择性(优于N_(2))。同时,利用气体吸附密度分布揭示了不同AM修饰的NY/NDY(AM-NY、AM-NDY)具有高吸附量的原因,以及二者作用效果差异的本质。最后,从吸附热、库仑和范德瓦耳斯相互作用等角度详细说明了AM引入的改性机制。