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951.
Molecular Diodes: Stable Molecular Diodes Based on π–π Interactions of the Molecular Frontier Orbitals with Graphene Electrodes (Adv. Mater. 10/2018) 下载免费PDF全文
952.
A C-band mode-locked fibre laser incorporating a boron nitride-doped graphene oxide (BN-GO)-based saturable absorber (SA) is proposed and demonstrated. The SA is fabricated by depositing multiple layers of synthesized BN-GO nanoparticles onto the polished surface of a side-polished fibre, which is then inserted into an erbium-doped fibre laser cavity to generate the desired pulsed output. The strong nonlinear optical response and light absorption of the BN-GO nanoparticles induces the generation of a highly stable mode-locked pulse at 1567.32?nm with visible Kelly’s sidebands. The pulses have a measured repetition rate of 13.56?MHz and a pulse width of 1.18?ps at the maximum pump power of 280.5?mW. The pulses have a frequency signal-to-noise ratio of ~53?dB, indicating a highly stable output. The proposed laser would find significant telecommunications applications, particularly for dense wavelength division multiplexing systems. 相似文献
953.
954.
Kewei Sun Penghui Ji Junjie Zhang Jinxi Wang Xuechao Li Xin Xu Haiming Zhang Lifeng Chi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(15)
Armchair graphene nanoribbons (AGNRs) with 8 and 10 carbon atoms in width (8‐ and 10‐AGNRs) are synthesized on Au (111) surfaces via lateral fusion of nanoribbons that belong to different subfamilies. Poly‐para‐phenylene (3‐AGNR) chains are pre‐synthesized as ladder ribbons on Au (111). Subsequently, synthesized 5‐ and 7‐AGNRs can laterally fuse with 3‐AGNRs upon annealing at higher temperature, producing 8‐ and 10‐AGNRs, respectively. The synthetic process, and their geometric and electronic structures are characterized by scanning tunneling microscopy/spectroscopy (STM/STS). STS investigations reveal the band gap of 10‐AGNR (2.0 ± 0.1 eV) and a large apparent band gap of 8‐AGNRs (2.3 ± 0.1 eV) on Au (111) surface. 相似文献
955.
Xiao Wang Qiaoxia Li Penghui Shi Jinchen Fan Yulin Min Qunjie Xu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(48)
Hydrogen is regarded as the most promising green clean energy in the 21st century. Developing the highly efficient and low‐cost electrocatalysts for oxygen evolution reaction (OER) is of great concern for the hydrogen industry. In the water electrolyzed reaction, the overpotential and the kinetics are the main hurdles for OER. Therefore, an efficient and durable oxygen evolution reaction electrocatalyst is required. In this study, an activated graphene (AG)–black phosphorus (BP) nanosheets hybrid is fabricated for supporting Ni3N particles (Ni3N/BP‐AG) in the application of OER. The Ni3N particles are combined with the BP‐AG heterostructure via facile mechanical ball milling under argon protection. The synthesized Ni3N/BP‐AG shows excellent catalytic performance toward the OER, demanding the overpotential of 233 mV for a current density of 10 mA cm?2 with a Tafel slope of 42 mV dec?1. The Ni3N/BP‐AG catalysts also show remarkable stability with a retention rate of the current density of about 86.4% after measuring for 10 000 s in potentiostatic mode. 相似文献
956.
Junyao Li Hang Heng Jianlin Lv Tingting Jiang Zhaoyin Wang Zhihui Dai 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(48)
Fabrication of high‐performance surface‐enhanced Raman scattering (SERS) biosensors relies on the coordination of SERS substrates and sensing strategies. Herein, a SERS active AuCu alloy with a starfish‐like structure is prepared using a surfactant‐free method. By covering the anisotropic AuCu alloy with graphene oxide (GO), enhanced SERS activity is obtained owing to graphene‐enhanced Raman scattering and assembly of Raman reporters. Besides, stability of SERS is promoted based on the protection of GO to the AuCu alloy. Meanwhile, it is found that SERS activity of AuCu/GO can be regulated by DNA. The regulation is sequence and length dual‐dependent, and short polyT reveals the strongest ability of enhancing the SERS activity. Relying on this phenomenon, a SERS biosensor is designed to quantify apurinic/apyrimidinic endonuclease 1 (APE1). Because of the APE1‐induced cycling amplification, the biosensor is able to detect APE1 sensitively and selectively. In addition, APE1 in human serum is analyzed by the SERS biosensor and enzyme‐linked immunosorbent assay (ELISA). The data from the SERS method are superior to that from ELISA, indicating great potential of this biosensor in clinical applications. 相似文献
957.
Ultrafast degradation of common organic dyes in presence of gadolinium oxide/graphene oxide in water
Yong Wu He Qiang Wang Xin Yan Le Qin He 《Fullerenes, Nanotubes and Carbon Nanostructures》2019,27(6):478-481
Gadolinium oxide/graphene oxide (Gd2O3/GO) nanocomposite has been prepared by a simple method in N,N-dimethylformamide (DMF) and employed as an excellent catalyst for common organic dyes degradation under ultrasound. The scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectrum (XPS) data revealed that the Gd2O3 nanoparticles were successfully attached on the surface of GO sheets. The High efficiencies of common dyes (methylene blue, methyl orange, methyl violet rhodamine B, fuchsin base, thymolphthalein, crystal violet and eosin) degradation within 15?min illustrated that the as-synthesized nanocomposite was an ultrafast, stable, recyclable, and economical material for environment related applications. 相似文献
958.
Donghun Lee Haeli Park Soo Deok Han Su Han Kim Woong Huh Jae Yoon Lee Yoon Seok Kim Myung Jin Park Won Il Park Chong‐Yun Kang Chul‐Ho Lee 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(2)
Ultralow power chemical sensing is essential toward realizing the Internet of Things. However, electrically driven sensors must consume power to generate an electrical readout. Here, a different class of self‐powered chemical sensing platform based on unconventional photovoltaic heterojunctions consisting of a top graphene (Gr) layer in contact with underlying photoactive semiconductors including bulk silicon and layered transition metal dichalcogenides is proposed. Owing to the chemically tunable electrochemical potential of Gr, the built‐in potential at the junction is effectively modulated by absorbed gas molecules in a predictable manner depending on their redox characteristics. Such ability distinctive from bulk photovoltaic counterparts enables photovoltaic‐driven chemical sensing without electric power consumption. Furthermore, it is demonstrated that the hydrogen (H2) sensing properties are independent of the light intensity, but sensitive to the gas concentration down to the 1 ppm level at room temperature. These results present an innovative strategy to realize extremely energy‐efficient sensors, providing an important advancement for future ubiquitous sensing. 相似文献
959.
Corvin Rive Giacomo Reina Prerana Wagle Emanuele Treossi Vincenzo Palermo Alberto Bianco Lucia Gemma Delogu Matthias Rieckher Bjrn Schumacher 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(45)
Graphene oxide (GO) holds high promise for diagnostic and therapeutic applications in nanomedicine but reportedly displays immunotoxicity, underlining the need for developing functionalized GO with improved biocompatibility. This study describes adverse effects of GO and amino‐functionalized GO (GONH2) during Caenorhabditis elegans development and ageing upon acute or chronic exposure. Chronic GO treatment throughout the C. elegans development causes decreased fecundity and a reduction of animal size, while acute treatment does not lead to any measurable physiological decline. However, RNA‐Sequencing data reveal that acute GO exposure induces innate immune gene expression. The p38 MAP kinase, PMK‐1, which is a well‐established master regulator of innate immunity, protects C. elegans from chronic GO toxicity, as pmk‐1 mutants show reduced tissue‐functionality and facultative vivipary. In a direct comparison, GONH2 exposure does not cause detrimental effects in the wild type or in pmk‐1 mutants, and the innate immune response is considerably less pronounced. This work establishes enhanced biocompatibility of amino‐functionalized GO in a whole‐organism, emphasizing its potential as a biomedical nanomaterial. 相似文献
960.
Marek E. Schmidt Manoharan Muruganathan Teruhisa Kanzaki Takuya Iwasaki Ahmed M. M. Hammam Shunei Suzuki Shinichi Ogawa Hiroshi Mizuta 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(46)
The predicted quasiparticle energy gap of more than 1 eV in sub‐6 nm graphene nanoribbons (GNRs) is elusive, as it is strongly suppressed by the substrate dielectric screening. The number of techniques that can produce suspended high‐quality and electrically contacted GNRs is small. The helium ion beam milling technique is capable of achieving sub‐5 nm patterning; however, the functional device fabrication and the electrical characteristics are not yet reported. Here, the electrical transport measurement of suspended ≈6 nm wide mono‐ and bilayer GNR functional devices is reported, which are obtained through sub‐nanometer resolution helium ion beam milling with controlled total helium ion budget. The transport gap opening of 0.16–0.8 eV is observed at room temperature. The measured transport gap of the different edge orientated GNRs is in good agreement with first‐principles simulation results. The enhanced electron–electron interaction and reduced dielectric screening in the suspended quasi‐1D GNRs and anti‐ferromagnetic coupling between opposite edges in the zigzag GNRs substantiate the observed large transport gap. 相似文献