Electronic sensors based on biomaterials can lead to novel green technologies that are low cost, renewable, and eco-friendly. Here we demonstrate bioelectronic ammonia sensors made from protein nanowires harvested from the microorganism Geobacter sulfurreducens. The nanowire sensor responds to a broad range of ammonia concentrations (10 to 106 ppb), which covers the range relevant for industrial, environmental, and biomedical applications. The sensor also demonstrates high selectivity to ammonia compared to moisture and other common gases found in human breath. These results provide a proof-of-concept demonstration for developing protein nanowire based gas sensors for applications in industry, agriculture, environmental monitoring, and healthcare.
相似文献On-demand hydrogen generation is desired for fuel cells, energy storage, and clean energy applications. Silicon nanowires (SiNWs) and nanoparticles (SiNPs) have been reported to generate hydrogen by reacting with water, but these processes usually require external assistance, such as light, electricity or catalysts. Herein, we demonstrate that a porous SiNWs array, which is fabricated via the metal-assisted anodic etching (MAAE) method, reacts with water under ambient and dark conditions without any energy inputs. The reaction between the SiNWs and water generates hydrogen at a rate that is about ten times faster than the reported rates of other Si nanostructures. Two possible sources of enhancement are discussed: SiNWs maintain their high specific surface area as they don’t agglomerate, and the intrinsic strain of the nanowires promotes the reactivity. Moreover, the porous SiNWs array is portable, reusable, and environmentally friendly, yielding a promising route to produce hydrogen in a distributed manner.
相似文献Nanoparticles (NPs) which are innovation and research focus in drug delivery systems, still have some disadvantages limiting its application in clinical use, such as short circulation time, recognition and clearance by reticuloendothelial system (RES) and passive targeting in certain organs. However, the recent combination of natural components and nanotechnology has offered new solutions to address these problems. A novel biomimetic platform consisting of nanoparticle core and membrane shell, such as cell membrane, exosome or vesicle vastly improves properties of nanoparticles. These coated nanoparticles can replicate the unique functions of the membrane, such as prolonged blood circulation, active targeting capability and enhanced internalization. In this review, we focus on the newest development of biological-camouflaged nanoparticles and mainly introduce its application related to cancer therapy and toll-like receptor.
相似文献Two-dimensional nanosheet membranes with responsive nanochannels are appealing for controlled mass transfer/separation, but limited by everchanging thicknesses arising from unstable interfaces. Herein, an interfacially stable, thermo-responsive nanosheet membrane is assembled from twin-chain stabilized metal-organic framework (MOF) nanosheets, which function via two cyclic amide-bearing polymers, thermo-responsive poly(N-vinyl caprolactam) (PVCL) for adjusting channel size, and non-responsive polyvinylpyrrolidone for supporting constant interlayer distance. Owing to the microporosity of MOF nanosheets and controllable interface wettability, the hybrid membrane demonstrates both superior separation performance and stable thermo-responsiveness. Scattering and correlation spectroscopic analyses further corroborate the respective roles of the two polymers and reveal the microenvironment changes of nanochannels are motivated by the dehydration of PVCL chains.
相似文献Oligo(p-phenyleneethynylene)s (OPEs) end-capped with (alkynyl)bis(diphosphine)ruthenium and thiol/thiolate groups stabilize ca. 2 nm diameter gold nanoparticles (AuNPs). The morphology, elemental composition and stability of the resultant organometallic OPE/AuNP hybrid materials have been defined using a combination of molecular- and nano-material chacterization techniques. The hybrids display long-term stability in solution (more than a month), good solubility in organic solvents, reversible ruthenium-centered oxidation, and transparency beyond 800 nm, and possess very strong nonlinear absorption activity at the first biological window, and unprecedented two-photon absorption activity in the second biological window (σ2 up to 38,000 GM at 1,050 nm).
相似文献As a promising graphene analogue, two-dimensional (2D) polymer nanosheets with unique 2D features, diversified topological structures and as well as tunable electronic properties, have received extensive attention in recent years. Here in this review, we summarized the recent research progress in the preparation methods of 2D polymer nanosheets, mainly including interfacial polymerization and solution polymerization. We also discussed the recent research advancements of 2D polymer nanosheets in the fields of energy storage and conversion applications, such as batteries, supercapacitors, electrocatalysis and photocatalysis. Finally, on the basis of their current development, we put forward the existing challenges and some personal perspectives.
相似文献Atomic non-noble metal materials show the potential to substitute noble metals in catalysis. Herein, melamine formaldehyde resin is developed to synthesize atomic iron on mesoporous nitrogen-doped carbon. The triazine units with abundant nitrogen content and cavity can realize effectively anchoring of single metal atoms. The atomic iron with unique charge and coordination characteristics shows superior catalytic performance in dehydrogenation reaction. Various N-heterocycles compounds and amines can be efficiently dehydrogenated into the corresponding products at room temperature, which is the mildest of all reported reaction conditions even when noble metal catalysts are considered. Therefore, development of atomic non-noble metal catalysts with mesoporous structure may provide an effective way to realize the substitution for noble metals in heterogeneous catalysis.
相似文献DNA-based nanofabrication of inorganic nanostructures has potential application in electronics, catalysis, and plasmonics. Previous DNA metallization has generated conductive DNA-assembled nanostructures; however, the use of semiconductors and the development of well-connected nanoscale metal—semiconductor junctions on DNA nanostructures are still at an early stage. Herein, we report the first fabrication of multiple electrically connected metal—semiconductor junctions on individual DNA origami by location-specific binding of gold and tellurium nanorods. Nanorod attachment to DNA origami was via DNA hybridization for Au and by electrostatic interaction for Te. Electroless gold plating was used to create nanoscale metal—semiconductor interfaces by filling the gaps between Au and Te nanorods. Two-point electrical characterization indicated that the Au—Te—Au junctions were electrically connected, with current—voltage properties consistent with a Schottky junction. DNA-based nanofabrication of metal—semiconductor junctions opens up potential opportunities in nanoelectronics, demonstrating the power of this bottom-up approach.
相似文献With the slowing down of the Moore’s law and fundamental limitations due to the von-Neumann bottleneck, continued improvements in computing hardware performance become increasingly more challenging. Resistive switching (RS) devices are being extensively studied as promising candidates for next generation memory and computing applications due to their fast switching speed, excellent endurance and retention, and scaling and three-dimensional (3D) stacking capability. In particular, RS devices offer the potential to natively emulate the functions and structures of synapses and neurons, allowing them to efficiently implement neural networks (NNs) and other in-memory computing systems for data intensive applications such as machine learning tasks. In this review, we will examine the mechanisms of RS effects and discuss recent progresses in the application of RS devices for memory, deep learning accelerator, and more faithful brain-inspired computing tasks. Challenges and possible solutions at the device, algorithm, and system levels will also be discussed.
相似文献The development of magnetic two-dimensional (2D) materials in its infancy has generated an enormous amount of attention as it offers an ideal platform for the exploration of magnetic properties down to the 2D limit, paving the way for spintronic devices. Due to the nonnegligible advantages including time efficiency and simplified process, the facile bottom-up chemical vapor deposition (CVD) is regarded as a robust method to fabricate ultrathin magnetic nanosheets. Recently, some ultrathin magnets possessing fascinating properties have been successfully synthesized via CVD. Here, the recent researches toward magnetic 2D materials grown by CVD are systematically summarized with special emphasis on the fabrication methods. Then, heteroatoms doping and phase transition induced in CVD growth to bring or tune the magnetic properties in 2D materials are discussed. Characterizations and applications of these magnetic materials are also discussed and reviewed. Finally, some perspectives in need of urgent attention regarding the development of CVD-grown magnetic 2D materials are proposed.
相似文献The remarkable ability of biological systems to sense and adapt to complex environmental conditions has inspired the design of next-generation electronics with advanced functionalities. This review focuses on emerging bio-inspired strategies for the development of flexible and stretchable electronics that can accommodate mechanical deformations and integrate seamlessly with biological systems. We will provide an overview of the practical considerations in the materials and structure designs of flexible and stretchable electronics. Recent progress in bio-inspired pressure/strain sensors, stretchable electrodes, mesh electronics, and flexible energy devices are then discussed, with an emphasis on their unconventional micro/nanostructure designs and advanced functionalities. Finally, current challenges and future perspectives are identified and discussed.
相似文献