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21.
《印度化学会志》2023,100(4):100962
In the proposed work, an investigation of shielding effectiveness (SE) for varying compositions of Graphene, Multiwall carbon nanotubes (MWCNT), and Iron nanoparticles coated on Graphite (Fe@Graphite) was conducted in X-band (8.2 GHz–12.4 GHz). All these are mixed in an LDPE matrix. The nanomaterial was subjected to chemical characterization, i.e., Scanning electron microscopy (SEM), X-ray diffraction (XRD), and vibrating sample magnetometry (VSM). The shielding observed is dominantly due to absorption. The lattice structure which facilitates the shielding due to absorption was the hexagonal graphite structure on whose surface iron nanoparticles were embedded and used as the magnetic filler. At the same time, Graphene and MWCNT act as electrically conducting fillers. The Total shielding effectiveness(SET) was maximum for LDPE, MWCNT, Graphene, and Fe@Graphite, in the ratio of 50: 5: 25: 20 by weight %, and is 49 dB at 9.65 GHz for a sample thickness of 3 mm. 相似文献
22.
Haojie Zhu Fangcheng Wang Lu Peng Tingting Qin Prof. Feiyu Kang Prof. Cheng Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202212439
Rechargeable aqueous sodium ion batteries (ASIBs) are rising as an important alternative to lithium ion batteries, owing to their safety and low cost. Metal anodes show a high theoretical capacity and nonselective hydrated ion insertion for ASIBs, yet their large volume expansion and sluggish reaction kinetics resulted in poor electrochemical stability. Herein, we demonstrate an electrode cyclability enhancement mechanism by inlaying bismuth (Bi) nanoparticles on graphene nanosheets through chemical bond, which is achieved by a unique laser induced compounding method. This anchored metal-graphene heterostructure can effectively mitigate volume variation, and accelerate the kinetic capability as the active Bi can be exposed to the electrolyte. Our method can achieve a reversible capacity of 122 mAh g−1 at a large current density of 4 A g−1 for over 9500 cycles. This finding offers a desirable structural design of other metal anodes for aqueous energy storage systems. 相似文献
23.
Design and Development of a Non-Enzymatic Electrochemical Biosensor for the Detection of Glutathione
Shrute Kannappan Lakshmishri Prabakaran Noel Nesakumar K. Jayanth Babu Arockia Jayalatha Kulandaisamy Prof. John Bosco Balaguru Rayappan 《Electroanalysis》2023,35(1):e202100650
Glutathione (GSH-reduced form) is a tripeptide that plays a vital role as an antioxidant to remove xenobiotics in the human body and changes in GSH levels are a marker for the progression of various diseases. In this context, a highly sensitive non-enzymatic electrochemical biosensor for the detection of GSH has been developed using reduced graphene oxide Manganese oxide (rGMnO) nanocomposite as the nano-interface. Initially, graphene oxide was synthesized by Hummer's method and then thermally reduced in the presence of MnO2 in a blast furnace to obtain rGMnO nanocomposite. The nanocomposite was characterized to validate its structure and morphological properties via Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS). Cyclic voltammetry and amperometry studies showed that upon the addition of GSH, the Pt/rGMnO modified working electrode exhibited a linear response in the range of 1–100 μM at an input voltage of −0.62 V. The developed sensor was found to have a sensitivity of 0.3256 μA μM−1 and LOD of 970 nM with a recovery of 92–104 % in real blood serum samples. 相似文献
24.
Hassan Nabizadeh Bahareh Feyzi Amir Ahmad Salarian Seyed Reza Abtahi Ali Mohammadi Zahra Hami 《Electroanalysis》2023,35(1):e202200022
The development of selective and simple methods for the determination of different analytes is of great interest. This is the first time to show the applicability of graphene oxide-chitosan (GO-CS) nanocomposite for designing an electrochemical nanosensor for determination of Amlodipine, Valsartan, and Hydrochlorothiazide, simultaneously. Differential pulse voltammetrics current of AML, HCT, and VAL increased linearly in the ranges of 0.1–110, 0.1–110, and 1–230 μM with LOD of 5.5×10−2, 3.5×10−2 and 8.6×10−2 μM, respectively. Finally, GO-CS/GCE was used for the detection of these drugs in commercial tablets and compared with the reference method (HPLC). 相似文献
25.
Hong Zhang Chenxu Zhao Jianxi Yao Wallace C. H. Choy 《Angewandte Chemie (International ed. in English)》2023,62(24):e202219307
Advancing inverted (p-i-n) perovskite solar cells (PSCs) is critical for commercial applications given their compatibility with different bottom cells for tandem photovoltaics, low-temperature processability (≤100 °C), and promising operational stability. Although inverted PSCs have achieved an efficiency of over 25 % using doped or expensive organic hole transport materials (HTMs), their synthesis cost and stability still cannot meet the requirements for their commercialization. Recently, dopant-free and low-cost non-stoichiometric nickel oxide nanocrystals (NiOx NCs) have been extensively studied as a low-cost and effective HTM in perovskite optoelectronics. In this minireview, we summarize the synthesis and surface-functionalization methods of NiOx NCs. Then, the applications of NiOx NCs in other perovskite optoelectronics beyond photovoltaics are discussed. Finally, we provide a perspective for the future development of NiOx NCs for the commercialization of perovskite optoelectronics. 相似文献
26.
Guanghui Feng Dr. Shibin Wang Prof. Shenggang Li Ruipeng Ge Dr. Xuefei Feng Prof. Junwei Zhang Dr. Yanfang Song Dr. Xiao Dong Jiazhou Zhang Prof. Gaofeng Zeng Prof. Qiang Zhang Prof. Guijun Ma Dr. Yi-De Chuang Prof. Xixiang Zhang Prof. Jinghua Guo Prof. Yuhan Sun Prof. Wei Wei Prof. Wei Chen 《Angewandte Chemie (International ed. in English)》2023,62(15):e202218664
Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO2), i.e., artificial photosynthesis (AP) is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C2 compounds with a high CO2 conversion rate remains challenging for current AP technologies. We performed CO2 photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C2H5OH) selectivity of>99 % and a CO2 conversion rate of up to 17.1 mmol gcat−1 h−1 with sustained performance. Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few-layer graphene overlayer, which also favored an efficient CO2 to C2H5OH conversion pathway. 相似文献
27.
Dr. Wenhui Niu Dr. Yubin Fu Gianluca Serra Kun Liu Jörn Droste Yeonju Lee Zhitian Ling Dr. Fugui Xu Dr. José D. Cojal González Dr. Andrea Lucotti Prof. Dr. Jürgen P. Rabe Prof. Dr. Michael Ryan Hansen Prof. Dr. Wojciech Pisula Prof. Dr. Paul W. M. Blom Prof. Dr. Carlos-Andres Palma Prof. Dr. Matteo Tommasini Prof. Dr. Yiyong Mai Dr. Ji Ma Prof. Dr. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2023,62(35):e202305737
The incorporation of nanopores into graphene nanostructures has been demonstrated as an efficient tool in tuning their band gaps and electronic structures. However, precisely embedding the uniform nanopores into graphene nanoribbons (GNRs) at the atomic level remains underdeveloped especially for in-solution synthesis due to the lack of efficient synthetic strategies. Herein we report the first case of solution-synthesized porous GNR ( pGNR ) with a fully conjugated backbone via the efficient Scholl reaction of tailor-made polyphenylene precursor ( P1 ) bearing pre-installed hexagonal nanopores. The resultant pGNR features periodic subnanometer pores with a uniform diameter of 0.6 nm and an adjacent-pores-distance of 1.7 nm. To solidify our design strategy, two porous model compounds ( 1 a , 1 b ) containing the same pore size as the shortcuts of pGNR , are successfully synthesized. The chemical structure and photophysical properties of pGNR are investigated by various spectroscopic analyses. Notably, the embedded periodic nanopores largely reduce the π-conjugation degree and alleviate the inter-ribbon π–π interactions, compared to the nonporous GNRs with similar widths, affording pGNR with a notably enlarged band gap and enhanced liquid-phase processability. 相似文献
28.
Jiahui Xian Suisheng Li Hui Su Peisen Liao Shihan Wang Runan Xiang Yawei Zhang Prof. Qinghua Liu Prof. Guangqin Li 《Angewandte Chemie (International ed. in English)》2023,62(30):e202306726
The conversion of industrial exhaust gases of nitrogen oxides into high-value products is significantly meaningful for global environment and human health. And green synthesis of amino acids is vital for biomedical research and sustainable development of mankind. Herein, we demonstrate an innovative approach for converting nitric oxide (NO) to a series of α-amino acids (over 13 kinds) through electrosynthesis with α-keto acids over self-standing carbon fiber membrane with CoFe alloy. The essential leucine exhibits a high yield of 115.4 μmol h−1 corresponding a Faradaic efficiency of 32.4 %, and gram yield of products can be obtained within 24 hours in lab as well as an ultra-long stability (>240 h) of the membrane catalyst, which could convert NO into NH2OH rapidly attacking α-keto acid and subsequent hydrogenation to form amino acid. In addition, this method is also suitable for other nitrogen sources including gaseous NO2 or liquidus NO3− and NO2−. Therefore, this work not only presents promising prospects for converting nitrogen oxides from exhaust gas and nitrate-laden waste water into high-value products, but also has significant implications for synthetizing amino acids in biomedical and catalytic science. 相似文献
29.
Tong Shen Dr. Ya Zou Dr. Xudong Hou Dr. Haipeng Wei Dr. Longbin Ren Liuying Jiao Prof. Jishan Wu 《Angewandte Chemie (International ed. in English)》2023,62(45):e202311928
Polycyclic aromatic hydrocarbons (PAHs) with a one-dimensional (1D), ribbon-like structure have the potential to serve as both model compounds for corresponding graphene nanoribbons (GNRs) and as materials for optoelectronics applications. However, synthesizing molecules of this type with extended π-conjugation presents a significant challenge. In this study, we present a straightforward synthetic method for a series of bis-peri-dinaphtho-rylene molecules, wherein the peri-positions of perylene, quaterrylene, and hexarylene are fused with naphtho-units. These molecules were efficiently synthesized primarily through intramolecular or intermolecular radical coupling of in situ generated organic radical species. Their structures were confirmed using X-ray crystallographic analysis, which also revealed a slightly bent geometry due to the incorporation of a cyclopentadiene ring at the bay regions of the rylene backbones. Bond lengh analysis and theoretical calculations indicate that their electronic structures resemble pyrenacenes more than quinoidal rylenes. That is, the aromatic sextets are predominantly localized along the long axis of the skeletones. As the chain length increases, these molecules exhibit enhanced electronic absorption with a bathochromic shift, and multiple amphoteric redox waves. This study introduces a novel synthetic approach for generating 1D extended PAHs and GNRs, along with their structure-dependent electronic properties. 相似文献
30.
Chathuranga S. L. Rathnamalala Selena Hernandez Dr. Melissa Y. Lucero Chelsea B. Swartchick Dr. Abdul Kalam Shaik Prof. Dr. Nathan I. Hammer Amanda K. East Prof. Dr. Steven R. Gwaltney Prof. Dr. Jefferson Chan Prof. Dr. Colleen N. Scott 《Angewandte Chemie (International ed. in English)》2023,62(13):e202214855
Shortwave infrared (SWIR) dyes are characterized by their ability to absorb light from 900 to 1400 nm, which is ideal for deep tissue imaging owing to minimized light scattering and interference from endogenous pigments. An approach to access such molecules is to tune the photophysical properties of known near-infrared dyes. Herein, we report the development of a series of easily accessible (three steps) SWIR xanthene dyes based on a dibenzazepine donor conjugated to thiophene ( SCR-1 ), thienothiophene ( SCR-2 ), or bithiophene ( SCR-3 ). We leverage the fact that SCR-1 undergoes a bathochromic shift when aggregated for in vivo studies by developing a ratiometric nanoparticle for NO ( rNP-NO ), which we employed to successfully visualize pathological levels of nitric oxide in a drug-induced liver injury model via deep tissue SWIR photoacoustic (PA) imaging. Our work demonstrates how easily this dye series can be utilized as a component in nanosensor designs for imaging studies. 相似文献