1 1.中国石油大学(华东) 新能源学院, 青岛266580
2 2.山东能源集团有限公司新能源事业部, 济宁 273500
3 3.西安交通大学 材料科学与工程学院, 西安 710049
气体扩散层(GDL)是质子交换膜燃料电池(PEMFCs)的关键部件之一, 成本占燃料电池膜电极的40%~50%。开发低成本、高性能的GDL生产工艺, 可以降低燃料电池成本, 推动燃料电池商业化进程。本研究以纤维素棉布为原料, 通过铁基化合物的催化石墨化作用, 在较低温度(1500 ℃)下生成了一种高导电、高孔隙率的柔性生物质碳布。碳布由相互连接的微米级碳纤维组成, 形成了丰富的孔道, 其孔隙率为76.93%。经过铁基化合物催化, 碳纤维的表面原位生成了大量碳纳米管团簇, 增加了碳布的导电性, 使其平面电阻率降低至34 mΩ·cm, 垂直电阻率在 2 MPa压力下降低至2.8 mΩ·cm, 性能达到商业碳布的标准。生物质碳布作为气体扩散层的燃料电池在0.7 A·cm-2电流密度处功率密度达到0.4 W·cm-2, 超过了相同催化剂(Pt)负载量的商业碳布(0.34 W·cm-2)的电池功率密度。本研究制备的生物质碳布制备简单、价格低廉、性能优秀, 为开发低成本、高性能气体扩散层提供了新的思路。
生物质 碳布 碳纳米管 气体扩散层 燃料电池 biomass carbon cloth carbon nanotube gas diffusion layer fuel cell
1 1.昆明理工大学 材料科学与工程学院，昆明 650031
2 2.塔什干都灵工业大学, 塔什干 100095, 乌兹别克斯坦
光催化以其反应条件温和、能直接利用太阳能转化为化学能的优势, 而备受科研人员的关注。如何拓展光谱吸收范围及阻止光生“电子-空穴”复合, 是目前光催化研究领域的热点。本工作通过阳极氧化制备出非晶TiO2纳米管(TiO2NTs), 利用机械液压法将熔融铟锡合金压入非晶TiO2中, 得到In9.45Sn1/TiO2NTs, 再经高温煅烧后得到ITO/TiO2NTs复合材料。实验对比了TiO2NTs、In9.45Sn1/TiO2NTs与ITO/TiO2NTs对去除水溶液中亚甲基蓝的光催化性能, 在180 min光照下, ITO/TiO2NTs的降解效果最佳, 降解效率达96.14%。利用紫外-可见漫反射光谱(UV-Vis DRS)研究了TiO2NTs、In9.45Sn1/TiO2NTs和ITO/TiO2NTs的光吸附性能, ITO/TiO2NTs的吸光度最强。结合瞬态光电流响应、光电流密度电势、电化学阻抗谱和Mott-Schottky测试结果可知, ITO/TiO2NTs比TiO2NTs具有更高的电荷转移能力和供体密度, 抑制了空穴和电子的复合, 从而增强光电化学性能。经过五次循环后, ITO/TiO2NTs的降解效率保持在90.28%。自由基捕获实验结果表明, •O2-和•OH是光催化降解的主要活性物质。
二氧化钛 ITO 纳米管阵列 亚甲基蓝 机械液压法 titania ITO nanotube array methylene blue mechanical hydraulic method
1 上海电力大学 电子与信息工程学院, 上海 200090
2 深圳锐越微技术有限公司, 广东 深圳 518172
无结纳米管场效应晶体管(JLNT-FET)和反转模式纳米管场效应晶体管(IMNT-FET)因具有较好的驱动能力和对短沟道效应 (SCE) 卓越的抑制能力而被关注, 自热效应 (SHE)作为影响其电热性能的关键问题而被广泛研究。文章基于TCAD数值仿真, 通过对环境温度(TA)、接触热阻(Rtc)以及侧墙长度(LS)对体传导的JLNT-FET和表面传导的IMNT-FET的最大晶格温度(TLmax)、最大载流子温度(TCmax)、漏极电流(IDS)和栅极泄漏电流(IG)等器件参数影响的分析, 对比研究了JLNT-FET和IMNT-FET中传导机制对电热特性的影响。结果表明, 较高的TA、较大的Rtc及较小的LS, 都会加剧器件的声子散射, 导致严重的SHE。同时, 由于传导机制的差异, 体传导受界面散射和声子散射影响较小, JLNT-FET具有更好的电热特性。
无结纳米管场效应晶体管 反转模式纳米管场效应晶体管 电热特性 自热效应 热载流子注入 junctionless nanotube FET inversion-mode nanotube FET electrothermal self-heating effect hot carrier injection
Author Affiliations
Abstract
1 Institute of Animal Quarantine, Chinese Academy of Inspection and Quarantine, Beijing100176, China
2 Chinese Academy of Inspection and Quarantine Center for Biosafety, Sanya 572024, China
3 National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
The rapid spread of viral zoonoses can cause severe consequences, including huge economic loss, public health problems or even global crisis of society. Clinical detection technology plays a very important role in the prevention and control of such zoonoses. The rapid and accurate detection of the pathogens of the diseases can directly lead to the early report and early successful control of the diseases. With the advantages of being easy to use, fast, portable, multiplexing and cost-effective, semiconductor biosensors are kinds of detection devices that play an important role in preventing epidemics, and thus have become one of the research hotspots. Here, we summarized the advances of semiconductor biosensors in viral zoonoses detection. By discussing the major principles and applications of each method for different pathogens, this review proposed the directions of designing semiconductor biosensors for clinical application and put forward perspectives in diagnostic of viral zoonoses.The rapid spread of viral zoonoses can cause severe consequences, including huge economic loss, public health problems or even global crisis of society. Clinical detection technology plays a very important role in the prevention and control of such zoonoses. The rapid and accurate detection of the pathogens of the diseases can directly lead to the early report and early successful control of the diseases. With the advantages of being easy to use, fast, portable, multiplexing and cost-effective, semiconductor biosensors are kinds of detection devices that play an important role in preventing epidemics, and thus have become one of the research hotspots. Here, we summarized the advances of semiconductor biosensors in viral zoonoses detection. By discussing the major principles and applications of each method for different pathogens, this review proposed the directions of designing semiconductor biosensors for clinical application and put forward perspectives in diagnostic of viral zoonoses.
semiconductor biosensor viral zoonoses graphene silicon nanowire carbon nanotube Journal of Semiconductors
2023, 44(2): 023102
Author Affiliations
Abstract
1 State Key Laboratory of Fluid Power and Mechatronic Systems, School of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China
2 Department of Mechanical Engineering, The University of Tokyo, Tokyo 113-8656, Japan
Carbon nanotube (CNT), particularly single-walled CNT, possesses exceptional properties, and can be utilized in many high-end applications including high-performance electronics. However, the atomic arrangement of a CNT determines its band structure, making the atomic-precision fabrication one of most important topics for the development of this material. In this perspective, the author gives a personal summary on the history, current status of the atomic-precision fabrication of CNT and outlines the remaining challenges as well as the possible paths that may lead the production of atomically precise CNTs from ‘fabrication’ to ‘manufacturing’.
atomic precision manufacturing carbon nanotube nanomaterial International Journal of Extreme Manufacturing
2022, 4(2): 023001
Author Affiliations
Abstract
1 Southern Federal University, Institute of Nanotechnologies, Electronics and Equipment Engineering, Shevchenko St., 2, Taganrog, 347922, Russia
2 Southern Federal University, Research Laboratory of Functional Nanomaterials Technology, Shevchenko St., 2, Taganrog, 347922, Russia
Recent studies have shown that nitrogen doping of carbon nanotubes (CNTs) can lead to the formation of piezoelectric properties in them, not characteristic of pure CNTs. In this work, nitrogen-doped CNTs were grown by plasma-enhanced chemical vapor deposition and the effect of the aspect ratio of the nanotube length to its diameter on its piezoelectric coefficient was shown. It was observed that as the aspect ratio of the nanotube increased from 7 to 21, the value of increased linearly from 7.3 to 10.7 pm/V. This dependence is presumably due to an increase in curvature-induced polarization because of an increase in the curvature and the number of bamboo-like “bridges” in the nanotube cavity formed as a result of the incorporation of pyrrole-like nitrogen into the nanotube structure. The obtained results can be used in the development of promising elements of nanopiezotronics (nanogenerators, memory elements, and strain sensors).Recent studies have shown that nitrogen doping of carbon nanotubes (CNTs) can lead to the formation of piezoelectric properties in them, not characteristic of pure CNTs. In this work, nitrogen-doped CNTs were grown by plasma-enhanced chemical vapor deposition and the effect of the aspect ratio of the nanotube length to its diameter on its piezoelectric coefficient was shown. It was observed that as the aspect ratio of the nanotube increased from 7 to 21, the value of increased linearly from 7.3 to 10.7 pm/V. This dependence is presumably due to an increase in curvature-induced polarization because of an increase in the curvature and the number of bamboo-like “bridges” in the nanotube cavity formed as a result of the incorporation of pyrrole-like nitrogen into the nanotube structure. The obtained results can be used in the development of promising elements of nanopiezotronics (nanogenerators, memory elements, and strain sensors).
Carbon nanotube nitrogen piezoelectric nanogenerator PFM Journal of Advanced Dielectrics
2022, 12(6): 2241001
1 共青科技职业学院机电工程学院, 九江 332020
2 海南科技职业大学机电工程学院, 海口 570100
3 江西晶纳新材料有限公司, 南昌 330000
4 南昌大学机电工程学院, 南昌 330000
利用艾奇逊炉分别在3 000 ℃和2 800 ℃下进行碳纳米管的提纯实验。利用ICP、EDS、TGA检测了提纯碳纳米管的主要催化金属含量、灼烧残余物含量; 用四探针薄膜电阻仪检测其电阻率; 利用SEM、XRD、FT-IR研究了不同温度提纯碳纳米管的组织结构变化和表面特点。研究结果表明, 艾奇逊炉在不同温度下提纯的碳纳米管都可以有效降低碳纳米管粉体中的催化金属含量和灼烧残余物含量, 满足动力电池导电剂要求。与原生碳纳米管比较, 3 000 ℃提纯的碳纳米管的电阻率显著下降, 石墨晶化程度提高; 而2 800 ℃提纯的碳纳米管的电阻率略有提高, 石墨晶化程度变化不大, 表面官能团数量减少。
碳纳米管 高温纯化 艾奇逊炉 体积电阻率 石墨晶化 carbon nanotube high temperature purifying Acheson furnace volume resistivity crystallization of graphite
1 辽宁工程技术大学材料科学与工程学院，辽宁 阜新 123000
2 辽宁工程技术大学矿业学院，辽宁 阜新 123000
以天然硅酸盐矿物还原制备硅负极材料，即可以继承天然矿物结构来提高硅材料的电化学性能，又具有低成本的特点。以天然埃洛石铝热还原的产物为原料，沥青为碳源，采用简单的蒸发溶剂的方法制备了硅碳复合材料。结果表明：硅是以直径为30 nm左右的纳米管形式存在，碳层均匀地包覆在硅纳米管上，使得硅碳复合材料的直径增大，碳层厚度约为7 nm，碳以无定形结构存在，碳包覆还导致比表面积下降。电化学测试表明，与硅纳米管相比，当包覆碳含量(质量分数)为15%时电化学性能最好，首次充放电容量分别为1 387.8 mA瘙簚h/g和1 615.7 mA瘙簚h/g，首次Coulombic效率达到85.9%。不但保持住了硅纳米管的首次充放电效率，循环性能得到大幅度提升，与硅纳米管的循环200次容量保持率38%相比，包覆碳含量为15%的循环200次容量保持率提高了45.8%。包覆碳含量为15%的硅/碳复合材料的500次循环后比容量为1 065.6 mA瘙簚h/g。容量保持率为76.8%。
埃洛石 硅/碳复合材料 硅纳米管 锂离子电池 负极材料 halloysite silicon/carbon composite silicon nanotube lithium-ion battery anode material
1 伊犁师范大学化学与环境科学学院, 伊宁 835000
2 塔城地区质量与计量检测所,塔城 834700
为克服TiO2纳米管在光电转换时电子-空穴复合率高和吸收光谱范围窄的缺陷,利用多酸H4SiW12O40(SiW12)和CsPbI3量子点对其协同修饰,采用电沉积法将SiW12沉积在TiO2纳米管上,制备了SiW12/TiO2纳米管复合薄膜; 使用高温热注射法合成出CsPbI3量子点,再通过化学浴沉积法沉积CsPbI3量子点到复合薄膜上,得到SiW12/CsPbI3/TiO2纳米管复合薄膜,探究SiW12沉积时间、CsPbI3沉积次数对TiO2纳米管光电性能的影响。利用扫描电子显微镜(SEM)、能谱仪(EDS)、透射电子显微镜(TEM)、X射线衍射(XRD)仪、红外分光光度计(FT-IR)、紫外-可见分光光度计(UV-Vis)对薄膜进行表征,使用电化学工作站测试薄膜的光电化学性能。结果表明: TiO2纳米管沉积多酸SiW12和CsPbI3量子点后,光吸收范围扩大、电荷转移电阻降低,光电转换效率得到显著提升,最高达到0.52%。说明SiW12和CsPbI3的协同作用很好地抑制了TiO2纳米管电子-空穴的复合,并拓宽了吸收光谱范围,提高了TiO2纳米管的光电转换效率。
二氧化钛纳米管 电子-空穴复合 吸收光谱 多酸 CsPbI3量子点 复合薄膜 光电转换效率 TiO2 nanotube electron-hole recombination absorption spectrum polyoxometalate CsPbI3 quantum dot composite film photoelectric conversion efficiency
