Read by QxMD icon Read

Graphen Oxide

Man Luo, Feng Wu, Mingsheng Long, Xiaoshuang Chen
Atomically thin two-dimensional materials including graphene, transition-metal dichalcogenides, black phosphorus and so forth have been considered as promising channel medias for electronic and optoelectronic devices in the past few years. However, the poor photoresponse time and the large dark current are the two major issues which greatly block their applications. Here, we report a vertical Au-WSe2-ITO (indium tin oxides) Schottky-junction photodetector with a broadband photoresponse from 550 nm to 950 nm and a stable photovoltaic responsivity of ~0...
August 15, 2018: Nanotechnology
Adam J Clancy, Mustafa K Bayazit, Stephen A Hodge, Neal T Skipper, Christopher A Howard, Milo S P Shaffer
Since the discovery of buckminsterfullerene over 30 years ago, sp2 -hybridised carbon nanomaterials (including fullerenes, carbon nanotubes, and graphene) have stimulated new science and technology across a huge range of fields. Despite the impressive intrinsic properties, challenges in processing and chemical modification continue to hinder applications. Charged carbon nanomaterials (CCNs), formed via the reduction or oxidation of these carbon nanomaterials, facilitate dissolution, purification, separation, chemical modification, and assembly...
August 15, 2018: Chemical Reviews
Seunghyun Hong, Yusuf Shi, Renyuan Li, Chenlin Zhang, Yong Jin, Peng Wang
Solar steam generation, due to its capability of producing clean water directly by solar energy, is emerging as a promising eco-friendly and energy-efficient technology to address global challenges of water crisis and energy shortage. Although diverse materials and architectures have been explored to improve solar energy utilization, high efficiency in solar steam generation could be accomplished only with external optical and thermal management. For the first time, we report a deployable, three-dimensional (3D) origami-based solar steam generator capable of near full utilization of solar energy...
August 15, 2018: ACS Applied Materials & Interfaces
Bagher Eftekhari-Sis, Zahra Rezazadeh, Ali Akbari, Mojtaba Amini
A nanosensor, based on 8-hydroxyquinoline functionalized graphene oxide, was developed for the fluorescence detection of Zn2+ . It showed high selectivity and sensitivity for Zn2+ ion in aqueous solution over other metal ions such as Li+ , Na+ , Ca2+ , Mg2+ , Al3+ , Cd2+ , Co2+ , Cu2+ , Hg2+ , Ni2+ , Pb2+ , Fe2+ , Fe3+ and Cr3+ . Due to the linearity of the emission intensity toward Zn2+ concentration, fluorescent technique could be used for the detection of Zn2+ ion even at very low concentrations.
August 14, 2018: Journal of Fluorescence
Yang Yu, Lihe Yan, Mengmeng Yue, Huanhuan Xu
Reduced graphene oxide (rGO) functionalized with silver nanoparticles (Ag NPs) is prepared using a femtosecond laser ablation in liquids method. By ablating the mixed aqueous solutions of silver nitrate and graphene oxide (GO) using femtosecond laser pulses, Ag ions and GO are simultaneously reduced and well-dispersed Ag NPs supported on rGO are obtained. The effect of laser power, irritation time and Ag ion concentration on the optical property and morphology of the products are systematically studied. The nonlinear optical responses of the functionalized graphene are studied using a nanosecond Z-scan technique...
July 2018: Royal Society Open Science
Matthew R Hauwiller, Layne Frechette, Matthew Jones, Justin C Ondry, Grant M Rotskoff, Phillip L Geissler, A Paul Alivisatos
Mechanisms of kinetically-driven nanocrystal shape transformations were elucidated by monitoring single particle etching of gold nanocrystals using in situ Graphene Liquid Cell TEM. By systematically changing the chemical potential of the oxidative etching and then quantifying the facets of the nanocrystals, non-equilibrium processes of atom removal could be deduced. Etching at sufficiently high oxidation potentials, both cube and rhombic dodecahedra (RDD)-shaped gold nanocrystals transform into kinetically-stable tetrahexahedra (THH)-shaped particles...
August 14, 2018: Nano Letters
Samaneh Kameli, Ali Mehrizad
Recent improvements based on heterojunction nanocomposites have opened new possibilities in photocatalysis. In this research, an ultrasound assisted co-precipitation method was used to fabricate silver, zinc sulfide, and reduced graphene oxide (Ag-ZnS/rGO) nanocomposite, and characterization results indicated that 3% Ag-ZnS spherical nanoparticles are successfully embedded in rGO matrix. The potential of the Ag-ZnS/rGO, as a visible light active photocatalyst, was assessed through optimizing degradation of Tetracycline (TC) by response surface methodology...
August 14, 2018: Photochemistry and Photobiology
Daniela Iannazzo, Alessandro Pistone, Stefania Ferro, Laura De Luca, Annamaria Monforte, Roberto Romeo, Maria Rosa Buemi, Christophe Pannecouque
Graphene quantum dots (GQD) are the next generation of nanomaterials with great potential in drug delivery and target-specific HIV inhibition. In this study we investigated the antiviral activity of graphene based nanomaterials by using water soluble GQD synthesized from multi-walled carbon nanotubes (MWCNT) through prolonged acidic oxidation and exfoliation and compared their anti-HIV activity with that exerted by reverse transcriptase inhibitors (RTI) conjugated with the same nanomaterial. The antiretroviral agents chosen in this study, CHI499 and CDF119, belong to the class of non-nucleoside reverse transcriptase inhibitors (NNRTI)...
August 14, 2018: Bioconjugate Chemistry
Dong Gyu Kim, Jong Han Choi, Duck-Kyun Choi, Sang Woo Kim
Electromagnetic (EM) wave emissions from wearable or flexible smart display devices can cause product malfunction and have a detrimental effect on human health. Therefore, EM shielding strategies are becoming increasingly necessary. Consequently, herein, we prepared a transparent acrylic polymer-coated/reduced graphene oxide/silver nanowire (Ag NW) (A/RGO/SAW) EM interference (EMI) shielding film via liquid-to-vapor pressure-assisted wet sintering. The film exhibited enhanced Ag NW network formation and antireflection (AR) effects...
August 14, 2018: ACS Applied Materials & Interfaces
Hong Li, Yanhui Li, Meng Wang, Zhen Niu, Xiutong Wang, Baorong Hou
For improving the photocathodic protection performance of TiO2 photoanode, ZnIn2S4/reduced graphene oxide (RGO)/TiO2 nanotubes (NTs) composite was synthesized by electrochemical anodizing combined with hydrothermal method. The photoelectrochemical and photocathodic protection properties of the ZnIn2S4/RGO/TiO2 composite were investigated in detail. Compared with pure TiO2 NTs, the ZnIn2S4/RGO/TiO2 composite showed a significant improvement in photocathodic protection performances. The photogenerated open circuit potential (OCP) drop of ZnIn2S4/RGO/TiO2 coupled with Q235 carbon steel (CS) in 3...
August 14, 2018: Nanotechnology
Xuehua Li, Jiansheng Qian, Xingge Guo, Liwei Shi
A novel polypyrrole nanowires coated by graphene oxide (PPy-NWs/GO) has been successfully synthesized by one-step electrochemical method, whose structure was different from previously reported PPy/GO composites. The microbial fuel cell equipped with PPy-NWs/GO as anode was fabricated and compared with PPy-NWs ones. The SEM images show that the synthesized PPy-NWs/GO materials possess more surface areas than PPy-NWs. The electrochemical analysis indicated that PPy-NWs/GO anode had lower charge transfer resistance, which may be attributed to synergistic effect of them...
August 2018: 3 Biotech
Sake Wang, Hongyu Tian, Chongdan Ren, Jin Yu, Minglei Sun
The structural, electronic, and optical properties of heterostructures formed by transition metal dichalcogenides MX2 (M = Mo, W; X = S, Se) and graphene-like zinc oxide (ZnO) were investigated using first-principles calculations. The interlayer interaction in all heterostructures was characterized by van der Waals forces. Type-II band alignment occurs at the MoS2 /ZnO and WS2 /ZnO interfaces, together with the large built-in electric field across the interface, suggesting effective photogenerated-charge separation...
August 13, 2018: Scientific Reports
Pranay Ranjan, Shweta Agrawal, Apurva Sinha, T Rajagopala Rao, Jayakumar Balakrishnan, Ajay D Thakur
A low cost, non-explosive process for the synthesis of graphene oxide (GO) is demonstrated. Using suitable choice of reaction parameters including temperature and time, this recipe does not require expensive membranes for filtration of carbonaceous and metallic residues. A pre-cooling protocol is introduced to control the explosive nature of the highly exothermic reactions during the oxidation process. This alleviates the requirement for expensive membranes and completely eliminates the explosive nature of intermediate reaction steps when compared to existing methods...
August 13, 2018: Scientific Reports
Indiran Muralisankar, Santhanam Agilan, Rajendran Selvakumar, Sundararajan Vairam
This study discusses the use of Co3 O4 impregnated graphene (CoOIG) as an efficient adsorbent for the removal of methyl violet (MV) dye from wastewater. CoOIG nanocomposites have been prepared by pyrolyzing paraffin wax with cobalt acetate. The synthesised nanocomposite was characterised by X-ray diffraction, field emission scanning electron microscope, transmission electron microscope, Fourier transform infrared spectroscope, Raman spectroscopy, and Brunauer-Emmett-Teller isotherm studies. The above studies indicate that the composites have cobalt oxide nanoparticles of size 51-58 nm embedded in the graphene nanoparticles...
September 2018: IET Nanobiotechnology
Kunal Biswas, Debashis De, Jaya Bandyopadhyay, Pintu Sen
Two different morphological forms of graphene nanosheets: improved reduced graphene oxide (IRGO) and modified reduced GO (rGO) (MRGO) have been synthesised by improved and modified methods, respectively. Physical characterisations of these graphene nanosheets were carried out using X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Colloidal stability of these nanosheets toward a selected bacterium (e.g. Staphylococcus aureus ) was ascertained by zeta potential. In the present study, the authors for the first time made an attempt to study and compare the potentialities of these two different forms of graphene nanosheets as efficient bactericidal agents...
September 2018: IET Nanobiotechnology
Sergey A Grigoriev, Vladimir N Fateev, Artem S Pushkarev, Irina V Pushkareva, Natalia A Ivanova, Valery N Kalinichenko, Mikhail Yu Presnyakov, Xing Wei
Reduced graphene oxide (RGO) and RGO modified by ozone (RGO-O) and fluorine (RGO-F) were synthesized. Pt nanoparticles were deposited on these materials and also on Vulcan XC-72 using the polyol method. The structural and electrochemical properties of the obtained catalysts were investigated in a model glass three-electrode electrochemical cell and in a laboratory PEM fuel cell. Among the RGO-based catalysts, the highest electrochemically active surface area (EASA) was obtained for the oxidized RGO supported catalyst...
August 10, 2018: Materials
Feiyan Liu, Dan Yang, Yawen Liu, Qianqian Cao, Yulian Sun, Qiong Wang, Hao Tang
The surface functional groups of GO have significant effects on the performances of GO-based gene delivery vector. In this work, the polyamidoamine (PAMAM) dendrimer and glycyrrhetinic acid (GA) were tethered onto the GO surface by one-step covalently cross-linking method. The micro-morphology, surface functional groups, and zeta potential of the obtained GO-PAMAM-GA hybrid were characterized and verified. The effects of GA amount in the hybrid on the dispersive property in cell culture medium, in vitro cytotoxicity to human hepatocarcinoma (SMMC-7721) and human embryonic kidney (HEK-293) cells, and gene (plasmid DNA of enhanced green fluorescent protein) transfection capacity were investigated in detail...
July 30, 2018: Colloids and Surfaces. B, Biointerfaces
Xin Wu, Hui Li, Ning Xiao
Medication obstruction of microscopic organisms has turned into a worldwide medical issue, as it makes the ordinary anti-toxins less effective. It is desperately expected to investigate novel antibacterial materials and create viable treatment techniques to defeat the medication obstruction of anti-infection agents. Herein, we effectively fabricated silver nanoparticles improved proline/graphene oxide nano-flakes (GO-Pro/n-Ag) as novel anti-pathogenic substance through simplistic technique. The property of the silver nanoparticles activated discharge gave amazing antibacterial and antifungal movement against the pathogenic microorganism...
July 18, 2018: Journal of Photochemistry and Photobiology. B, Biology
Siyong Gu, Chien-Te Hsieh, Tzu-Wei Lin, Chun-Yao Yuan, Yasser Ashraf Gandomi, Jeng-Kuei Chang, Jianlin Li
Graphene sheets that can exhibit electrical conducting and semiconducting properties are highly desirable and have potential applications in fiber communications, photodetectors, solar cells, semiconductors, and broadband modulators. However, there is currently no efficient method that is able to tune the band gap of graphene sheets. This work adopts an efficient atomic layer oxidation (ALO) technique to cyclically increase the oxidation level of graphene sheets, thus, tuning their electrical conductance, band-gap structure, and photoluminescence (PL) response...
August 13, 2018: Nanoscale
Hadi Beitollahi, Hadiseh Salimi, Mohammad Reza Ganjali
An electrode has been developed based on using a composite of hematoxylin/graphene/ZnO nanocomposite to modify a glassy carbon electrode (GCE). The electrode (HGGCE) was tested and found to be applicable for the voltammetric analysis of levodopa in the presence of vitamin B6 , theophylline and guaifenesin using a 0.1 M phosphate buffer solution (PBS) pH 7 as the solvent. The HGGCE was used as the working electrode in cyclic voltammetry (CV) and square wave voltammetry (SWV) studies on the electrochemical behavior of levodopa at its surface...
2018: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"