Unique Seamlessly Bonded CNT@Graphene Hybrid Nanostructure Introduced in an Interlayer for Efficient and Stable Perovskite Solar Cells

Carbon nanomaterials have been widely used as an interlayer for realizing efficient and stable perovskite solar cells (PSCs). Theoretically, the design of a carbon composite interlayer that combines excellent conductivity with a high specific surface area is a better strategy than the application of pure nanocarbons. Here, an unusual seamlessly bonded carbon nanotube@graphene (CNT@G) hybrid nanomaterial was strategically synthesized and demonstrated to behave as an efficient interlayer for realizing efficient and stable PSCs. Due to the advantage of the seamless bond, the as‐proposed hybrid nanostructure showed an apparent improvement compared to the use of CNTs only, graphene only, or a simple mixture of CNTs and graphene. The power conversion efficiency improved from 15.67% to 19.56% after introduction of the hybrid nanomaterial due to efficient carrier extraction, faster charge transport, and restrained carrier recombination. More importantly, PSCs with a CNT@G hybrid‐decorated hole transport layer (HTL) showed good thermal stability during a 50 h heat‐aging test at 100 °C and water stability under ambient humidity (30–50% relative humidity) for 500 h because the hybrid nanostructure exhibited an increased capability to block ion/molecule diffusion. Our results provide an alternative approach for fully exploring the potential application of nanocarbons in the development of high‐performance PSCs.     

用于超快宽带激光防护的共轭扭曲并苯高性能光限幅材料

高性能的光限幅对激光防护应用来说非常重要。虽然光限幅相关的研究持续了几十年,但是绝大多数的已知光限幅材料无法兼顾低限幅阈值、高线性透过率和宽带、超快响应。从实验和理论上报道一种基于共轭扭曲并苯分子的多功能光限幅材料。研究结果显示,借助等效三光子吸收,该材料能够在480~700 nm的光谱范围内实现光限幅并具备快速的响应能力。此外,样品还同时具备低限幅阈值（0.15 J/cm2）和极高的线性透过率（532 nm时92%）。该光限幅材料集以上所有优点于一身,在用于人眼和光子器件的超快激光防护领域具有巨大的前景。     

M13 Bacteriophage as Materials for Amplified Surface Enhanced Raman Scattering Protein Sensing

Because of their unique properties, nanomaterials have been actively investigated in recent years for biosensing applications. A typical approach for biomarker detection is to attach capture or detection antibodies to nanomaterials, allow the analyte to bind, and measure the resulting change in signal. While antibodies or aptamers possess at most one binding site each for the nanomaterial and analyte, it is shown that the high surface area filamentous M13 bacteriophage can be utilized as a scaffold for generating an amplified signal. Since only a few proteins at the tip of the micrometer‐long virus are involved in antigen binding, the rest of the bacteriophage can be augmented with hundreds of functional groups, each of which can bind to a specific nanomaterial. It is demonstrated that the combination of DNA‐modified M13 bacteriophage and surface enhanced Raman spectroscopy (SERS) active nanoparticles can be used to produce exponential gains in Raman signal compared to that of antibodies at the same antigen concentration. Because of these high sensitivities, Raman measurements can be made directly from individual silica microparticles, potentially enabling future single step identification and analysis of different proteins in complex mixtures, while avoiding additional processing steps or prepatterned microarrays.     

Recent Advances in Nanomaterials-Based FETs for SARS-CoV-2 (COVID-19 Virus) Diagnosis

The emergence of infectious diseases that are quickly spreading, like the coronavirus (COVID-19), necessitates the development of efficient biosensors that can quickly detect and identify pathogens. It is essential to create sensitive virus detection methods in order to stop a virus from spreading throughout the world. It is determined that field-effect transistors (FETs) made of nanomaterials are potential candidates for rapid virus identification due to how easily the electronic transport characteristics of such an atomically thin nanomaterial can be affected by perturbations. Various FETs in this review article are investigated that are based on nanoparticles, carbon nanotubes (CNT), graphene, graphene-oxide, and semiconducting transition metal dichalcogenides (TMDs) WSe₂ in order to show that they are promising biosensors in regards to quickly and precisely detect COVID-19. The conjugation of nanomaterials with proteins enables the direct delivery of antiviral agents to the host cells. This method also minimizes the off-target effects and enables the targeted interactions. This mechanism has produced encouraging results in regards to sensing or treating COVID-19. The high surface area and extremely small size of nanomaterials make them crucial in regards to the development of new detection methods. The point-of-care test method of detection is quick, simple, and user-friendly, and it only requires a small amount of a patient's blood. It does not require a laboratory or trained professionals. This overview of the current research that is conducted on nanomaterials will prove to be useful in the process of formulating strategies for the diagnosis, treatment, and vaccination of viruses in opinion. Finally, the conclusion of this review provides a summary of the current challenges and the future prospects.     

Fast and Ultraclean Approach for Measuring the Transport Properties of Carbon Nanotubes

In this work, a fast approach for the fabrication of hundreds of ultraclean field‐effect transistors (FETs) is introduced, using single‐walled carbon nanotubes (SWCNTs). The synthesis of the nanomaterial is performed by floating‐catalyst chemical vapor deposition, which is employed to fabricate high‐performance thin‐film transistors. Combined with palladium metal bottom contacts, the transport properties of individual SWCNTs are directly unveiled. The resulting SWCNT‐based FETs exhibit a mean field‐effect mobility, which is 3.3 times higher than that of high‐quality solution‐processed CNTs. This demonstrates that the hereby used SWCNTs are superior to comparable materials in terms of their transport properties. In particular, the on–off current ratios reach over 30 million. Thus, this method enables a fast, detailed, and reliable characterization of intrinsic properties of nanomaterials. The obtained ultraclean SWCNT‐based FETs shed light on further study of contamination‐free SWCNTs on various metal contacts and substrates.     

基于AuPd/CNT敏感材料的电化学传感器对对乙酰氨基酚的检测

金属纳米材料由于其自身优异的催化性能成为电化学催化剂发展最为迅速的一类催化材料,贵金属催化剂的性能尤为明显。本文利用湿化学法合成了粒径为(8.26±0.2)nm AuPd双金属纳米材料,并与多壁碳纳米管进行复合获得AuPd/CNT复合材料,以此作为敏感材料构建了电化学传感器。Au为主催化剂,Pd为助催化剂,双金属催化剂的协同作用有效地提升了催化性能。以AuPd双金属纳米材料构建的电化学传感器对对乙酰氨基酚(PA)的定量测定具有宽的线性范围(4~1000μmol/L)、低的检测限(0.05μmol/L)。将传感器用于感冒片剂中对乙酰氨基酚的定量测定取得满意的结果,表明AuPd双金属纳米材料在构建电化学传感器用于PA检测中具有良好的应用前景。     

Biomimetic Nanomaterial Strategies for Virus Targeting: Antiviral Therapies and Vaccines

The ongoing coronavirus disease 2019 (COVID-19) pandemic highlights the importance of developing effective virus targeting strategies to treat and prevent viral infections. Since virus particles are nanoscale entities, nanomaterial design strategies are ideally suited to create advanced materials that can interact with and mimic virus particles. In this progress report, the latest advances in biomimetic nanomaterials are critically discussed for combating viral infections, including in the areas of nanomaterial-enhanced viral replication inhibitors, biomimetic virus particle capture schemes, and nanoparticle vaccines. Particular focus is placed on nanomaterial design concepts and material innovations that can be readily developed to thwart future viral threats. Pertinent nanomaterial examples from the COVID-19 situation are also covered along with discussion of human clinical trial efforts underway that might lead to next-generation antiviral therapies and vaccines.     

Highly Sensitive Glucose Biosensors Based on Organic Electrochemical Transistors Using Platinum Gate Electrodes Modified with Enzyme and Nanomaterials

Organic electrochemical transistors with glucose oxidase‐modified Pt gate electrodes are successfully used as highly sensitive glucose sensors. The gate electrodes are modified with nanomaterials (multi‐wall carbon nanotubes or Pt nanoparticles) for the first time, which results in a dramatic improvement in the sensitivity of the devices. The detection limit of the device modified with Pt nanoparticles on the gate electrode is about 5 nM, which is three orders of magnitude better than a device without the nanoparticles. The improvement of the device performance can be attributed to the excellent electrocatalytic properties of the nanomaterials and more effective immobilization of enzyme on the gate electrodes. Based on the same principle, many other types of enzyme sensors with high sensitivity and low cost are expected to be realized by modifying the gate electrodes of organic electrochemical transistors with specific enzymes and nanomaterials.     

Accelerated Iron Oxide Nanoparticle Degradation Mediated by Polyester Encapsulation within Cellular Spheroids

Nanomaterials including gold nanoparticles, polymeric nanoparticles, and magnetic iron oxide nanoparticles are utilized in tissue engineering for imaging, drug delivery, and maturation. Prolonged presence of these nanomaterials within biological systems remains a concern due to potential adverse affects on cell viability and phenotype. Accelerating nanomaterial degradation within biological systems is expected to reduce the potential adverse effects in the tissue. Similar to biodegradable polymeric scaffolds, the ideal nanomaterial remains stable for sufficient time to accomplish its desired task, and then rapidly degrades once that task is completed. Here, surface modifications are reported to accelerate iron oxide MNP degradation mediated by polymer encapsulation, in which iodegradable coatings composed of FDA approved polymers with different degradation rates are used: poly(lactide) (PLA) or copolymer poly(lactide‐co‐glycolide) (PLGA). Results demonstrate that degradation of MNPs can be controlled by varying the content and composition of the polymeric nanoparticles used for MNP encapsulation (PolyMNPs). Incorporated into cellular spheroids, PolyMNPs maintain a high viability compared to non‐coated MNPs, and are also useful in magnetically patterning cellular spheroids into fused tissues for tissue engineering applications. Accelerated degradation compared to non‐coated MNPs makes PolyMNPs a viable alternative for removing nanomaterials from tissues after accomplishing their desired role.     

Deep Cavitand Self‐Assembled on Au NPs‐MWCNT as Highly Sensitive Benzene Sensing Interface

The unprecedented sensitivity and partial selectivity of quinoxaline‐walled thioether‐legged deep cavitand functionalized multiwall carbon nanotubes toward traces of benzene vapors are presented. The cavitand is grafted onto gold nanoparticle (Au‐NP) decorated oxygen plasma treated multiwall carbon nanotubes (O‐MWCNT) by a self‐assembled monolayer process affording a product referred to as cav‐Au‐MWCNT. The reported technique is suitable for the mass production of hybrid nanomaterials at low cost. The cav‐Au‐MWCNT resistive gas sensor operates at room temperature and shows an outstanding performance toward traces of benzene vapors. The detection of 2.5 ppb of benzene in dry air is demonstrated with a limit of detection (LOD) near 600 ppt. For the first time, it is shown that a CNT nanomaterial can effectively sense the extremely harmful benzene molecule with higher sensitivity than toluene or o‐xylene at the trace levels. The cavitand is well suited for binding benzene, which, being in close proximity to the MWCNT, affects its density of states (DOS) shifting the Fermi level away from the valence band. The binding of benzene is transduced in a diminution of MWCNT conductance. Furthermore, the inclusion of benzene is fully reversible at room temperature, implying that the sensor can operate at very low power consumption.     

Physical Reservoir Computing Based on Nanoscale Materials and Devices

Bioinspired computation systems can achieve artificial intelligence, bypassing fundamental bottlenecks and cost constraints. Computational frameworks suited for temporal/sequential data processing such as recurrent neural networks (RNNs) suffer from problems of high complexity and low efficiency. Physical systems assembled with nanoscale materials and devices represent as an alternative route to serve as the core component for physically implanted reservoir computing. In this review, an overview of the development of the paradigm of physical reservoir computing (PRC) is provided and the typical physical reservoirs constructed with nanomaterials and nanodevices are described. The physical reservoirs based on multiple nanomaterials overcome the problems of RNN, show strong robustness, and effectively deal with tasks with improved reliability and availability. Finally, the challenges and perspectives of nanomaterial and nanodevice-based PRC as a component of next-generation machine learning systems are discussed.     

Creation and physical properties of the molybdenum-containing polyethylene-based nanomaterials

The thermal decomposition of molybdenum carbonyl is employed for the creation of the composite nanomaterial that represents molybdenum-containing nanoparticles stabilized in the high-pressure polyethylene matrix. The resulting nanomaterials are studied using the transmission electron microscopy, X-ray phase analysis, and electron paramagnetic resonance. The experiments show that the Mo-containing nanoparticles have a mean size of 3–5 nm and consist of several components (Mo, MoC, MoO₃, and MoO₂). The concentration dependences of the electrophysical properties of the synthesized nanomaterials are analyzed.     

一维纳米材料排列方法的研究进展

基于国内外一维纳米材料器件的最新研究进展,系统综述了近年来一维纳米材料的排列方法,并介绍了磁场排列法、电场排列法、微流法、Langmiur-Blodgett等方法的原理和优缺点。同时,指出了一维纳米材料器件集成所面临的挑战,例如无法兼顾大规模有序排列与单一纳米材料精确定位排列等。最后,简单展望了一维纳米材料排列方法的发展趋势,传统排列方法,包括磁学方法和电学方法等的发展已经遇到了技术瓶颈,短时间内难以得到本质性的优化,生物技术也许会成为一维纳米材料有序排列的一个发展方向。     

飞秒激光组装一维纳米材料及其应用

一维纳米材料具有众多优异的特性,是构建微纳米功能性器件的基石。实现一维纳米材料在二维和三维空间的高精度和高定向组装是充分发挥其应用潜力的关键,同时也是制造难点。在众多纳米材料组装技术中,飞秒激光直写诱导组装技术具有独特优势,可实现一维纳米材料在任意三维结构中的可设计、高定向及高精度的组装。首先简要介绍了一维纳米材料组装研究的背景,并总结了非激光直写组装技术的研究现状和存在的挑战,然后较详细介绍了飞秒激光直写技术在一维纳米材料组装研究中的进展,重点回顾了金属(包括Au和Ag纳米线)、半导体(包括CNTs和ZnO)一维纳米材料的飞秒激光直写组装及微纳光电子功能器件的制造。并讨论了诱导一维纳米材料定向排布的光学力和非光学力(包括剪切力、体积收缩应力和空间限制)的作用机理,理论计算和实验研究结果验证了飞秒激光诱导的非光学力作用是导致一维纳米材料定向排布的主要原因。最后探讨了目前飞秒激光组装技术面临的一些问题和未来在高精度纳米材料组装和三维功能器件集成方面的发展趋势。     

2D Nanomaterial Supported Single-Metal Atoms for Heterogeneous Photo/Electrocatalysis

Single-atom catalysts (SACs) attract intensive attention owing to their unmatched catalytic activities and high atom utilization. Besides metal species themselves, the substrates play a key role for the improvement of their catalytic performance by optimizing metal–support interactions and coordination structures. In the past years, various 2D nanomaterials have been employed to anchor single metal atoms for renewable energy technologies and other important industrial processes. Tremendous progress has been achieved in the development of 2D supported SACs for advanced energy conversion reactions. This article provides a comprehensive and critical review of up-to-date advances in the field of 2D supported SACs. The state-of-the-art characterizations including ex/in situ microscopic and spectroscopic techniques are summarized with the emphasis on their specific superiorities in identifying the reactive sites and reaction mechanisms, combined with theoretical calculations and experimental results. A brief overview of various reactions including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), two-electron oxygen reduction reaction (2e-ORR), carbon dioxide reduction (CO₂RR), and nitrogen reduction reaction (NRR) under the framework of electrocatalysis and photocatalysis, is presented on basis of versatile 2D nanomaterial supports. Last, the key challenges and opportunities in this rising field are highlighted.     

Structural,optical and photocatalytic properties of ZnO nanoparticles modified with Cu

ZnO and ZnO modified with Cu nanoparticles have been prepared by a simple forced hydrolysis method. The concentration of Cu incorporated in ZnO ranged from 1% to 5% by atomic weight, and the influence of Cu concentration on the physical properties of ZnO and the relation to the photocatalytic performance has been investigated. The prepared ZnO and ZnO:Cu samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy and UV–vis transmittance spectroscopy. The results show that the ZnO nanomaterial was crystalline with the hexagonal wurtzite structure, with the preferential orientation of the grains along the (101) plane. The average grain size for samples with 1–5% Cu was in the range of 11–29 nm. The ZnO nanoparticles annealed at 420 °C showed an increased photocatalytic activity for the decomposition of methylene blue.     

Hybrid Antibacterial Fabrics with Extremely High Aspect Ratio Ag/AgTCNQ Nanowires

This study reports the synthesis of extremely high aspect ratios (>3000) organic semiconductor nanowires of Ag–tetracyanoquinodimethane (AgTCNQ) on the surface of a flexible Ag fabric for the first time. These one‐dimensional (1D) hybrid Ag/AgTCNQ nanostructures are attained by a facile, solution‐based spontaneous reaction involving immersion of Ag fabrics in an acetonitrile solution of TCNQ. Further, it is discovered that these AgTCNQ nanowires show outstanding antibacterial performance against both Gram negative and Gram positive bacteria, which outperforms that of pristine Ag. The outcomes of this study also reflect upon a fundamentally important aspect that the antimicrobial performance of Ag‐based nanomaterials may not necessarily be solely due to the amount of Ag+ ions leached from these nanomaterials, but that the nanomaterial itself may also play a direct role in the antimicrobial action. Notably, the applications of metal‐organic semiconducting charge transfer complexes of metal‐7,7,8,8‐tetracyanoquinodimethane (TCNQ) have been predominantly restricted to electronic applications, except from our recent reports on their (photo)catalytic potential and the current case on antimicrobial prospects. This report on growth of these metal‐TCNQ complexes on a fabric not only widens the window of these interesting materials for new biological applications, it also opens the possibilities for developing large‐area flexible electronic devices by growing a range of metal‐organic semiconducting materials directly on a fabric surface.     

Graphene Oxide Based Fluorescent DNA Aptasensor for Liver Cancer Diagnosis and Therapy

Graphene oxide (GO)-based fluorescent DNA aptasensors are promising nanomaterials in bioassays owing to the fluorescent ultrasensitivity and target identification ability. However, their in vivo application remains an appealing yet significantly challenging task. In this contribution, for the first time, a nanomaterial for in vivo diagnosis and therapy of liver tumors is demonstrated. A DNA nanomaterial consisting of DNA tetrahedron and aptamers, aggregation-induced emission luminogens, and antitumor drug doxorubicin, is fabricated and attached on the GO surface. This developed hybrid with good biocompatibility exhibits high selectivity to target liver cancer cells, and performs well in in vitro and in vivo liver tumor fluorescence imaging diagnosis and chemotherapy. Additionally, a GO-based fluorescent DNA nanodevice is also constructed by using microfluidic chips for liver tumor cell screening.     

Novel Fuzzy Adaptive Sensorless Induction Motor Drive

Investigations were carried out on a novel sensorless drive for induction motors, based on the combination of an open-loop (OL) estimator and a steady-state (SS) estimator. The novelty of this new sensorless structure is obtained by an intelligent mixing of the OL estimator response with the SS one. A fuzzy system weights the two estimated speed values according to the motor operating point. Then, the final speed value is obtained averaging the previously weighted speed values. Moreover, the OL estimator response is improved by means of using a fuzzy-controlled adaptive filter that selects the optimum cutoff frequency. The aim of this paper is to obtain a moderate performance sensorless drive for induction motors that could be easily implemented for industrial applications without a high computational effort. Simulation and experimental results illustrate the operation and performance of the proposed fuzzy-logic-based sensorless drive.     

用FeCl_3作催化剂先体制备碳纳米结构

以不同浓度的FeCl3溶液作为催化剂先体,利用乙醇催化燃烧法,在铜片上生长出了碳纳米管和碳纳米纤维。讨论了不同浓度的FeCl3催化剂先体对生长碳纳米材料产物和形貌的影响。利用扫描电镜,透射电镜和喇曼光谱对样品的形貌和结构进行了表征。实验结果表明,随着催化剂先体浓度增大,碳纳米材料产量增大,直径呈现增大趋势,其直径范围也逐渐变大。当催化剂先体浓度为0.01mol/L时,可以制备出直径较小的碳纳米管;当催化剂先体浓度为0.1mol/L时,可以制备出直径分布均匀的碳纳米管与碳纳米纤维的混合物;当催化剂先体浓度为1mol/L时,可以制备出直径分布不均匀的碳纳米纤维。