Search results for "Phene"

On the Reaction of 3-Bromo-2-nitrobenzo[b]thiophene 13C-Labeled at C-2 with 3-(Trifluoromethyl)aniline:  A Preliminary Insight into a Nucleophilic Su…

1997

The results of the title reaction have furnished proofs against a rearrangement of the carbon-atom skeleton and for a nitro group shift in the relevant nucleophilic substitution.

A High-Performance Asymmetric Supercapacitor Based on Tungsten Oxide Nanoplates and Highly Reduced Graphene Oxide Electrodes.

2021

Tungsten oxide/graphene hybrid materials are attractive semiconductors for energy-related applications. Herein, we report an asymmetric supercapacitor (ASC, HRG//m-WO3 ASC), fabricated from monoclinic tungsten oxide (m-WO3 ) nanoplates as a negative electrode and highly reduced graphene oxide (HRG) as a positive electrode material. The supercapacitor performance of the prepared electrodes was evaluated in an aqueous electrolyte (1 m H2 SO4 ) using three- and two-electrode systems. The HRG//m-WO3 ASC exhibits a maximum specific capacitance of 389 F g-1 at a current density of 0.5 A g-1 , with an associated high energy density of 93 Wh kg-1 at a power density of 500 W kg-1 in a wide 1.6 V ope…

A DFT Study of the [3+2] Cycloadditions of RCNO (R = H, Me and F) With Carbon Flatland Mimicking Graphene

2012

Graphene is the latest allotrope of carbon to be under the spotlight ever since its discovery by Novoselov and coworkers in 2004. Owing to its fascinating structural, electrical, optical, mechanical and thermal properties, graphene can be regarded as as a rapidly rising star in various fields such as supercapacitors, biosensors and batteries. The organic chemistry of graphene has stimulated a great deal of research and is gaining considerable attention. Among the various experimental studies which have been carried out on graphene, it is found that [3+2] cycloadditions (32CA) can also be achieved on graphene sheets and the resulting functionalized graphenes are dispersible in polar organic …

Direct Metal‐Free Chemical Vapor Deposition of Graphene Films on Insulating Substrates for Micro‐Supercapacitors with High Volumetric Capacitance

2019

Direct, metal‐free synthesis of graphene films on insulating substrates in a controlled manner is of great importance for applications in (opto)electronic and energy storage devices. Graphene films are fabricated on fused silica substrates without metal catalyst via chemical vapor deposition (CVD), using propionic acid as a carbon source. Film‐thickness is readily adjustable between 5 and 45 nm by changing the deposition time and flow rate of the precursor, displaying sheet resistance in the range of 0.27–1.86 kΩ□−1. The resulting graphene films are directly integrated into micro‐supercapacitors without film transfer or liquid‐phase processing, and demonstrate ultrahigh operation rates up t…

Research frontiers in energy-related materials and applications for 2020-2030

2020

Abstract: This article delineates the state of the art for several materials used in the harvest, conversion, and storage of energy, and analyzes the challenges to be overcome in the decade ahead for them to reach the market and benefit society. The materials covered have had a special interest in recent years and include perovskites, materials for batteries and supercapacitors, graphene, and materials for hydrogen production and storage. Looking at the common challenges for these different systems, scientists in basic research should carefully consider commercial requirements when designing new materials. These include cost and ease of synthesis, abundance of precursors, recyclability of s…

Cover Picture: Direct Metal‐Free Chemical Vapor Deposition of Graphene Films on Insulating Substrates for Micro‐Supercapacitors with High Volumetric …

2019

Energy Storage: Giant Enhancement in the Supercapacitance of NiFe–Graphene Nanocomposites Induced by a Magnetic Field (Adv. Mater. 28/2019)

2019

Magnetic Nanocomposites Formed by FeNi3 Nanoparticles Embedded in Graphene. Application as Supercapacitors

2013

A general family of magnetic nanocomposites formed by FeNi3 ferromagnetic nanoparticles (NPs) embedded in a graphitized carbon matrix is reported. The soft chemical approach used relies on the catalytic effect of the NPs resulting from the thermal decomposition of the layered double hydroxide precursor, which acts as a multilayered nanoreactor enabling the formation of a range of carbon nanoforms (CNFs). This is followed by acid treatment of the as-prepared nanocomposites to isolate the different CNFs formed. These range from carbon nano-onions to graphene depending on the temperature of the thermal decomposition. This synthetic process paves the way for the rational design of metal–carbon …

Bottom-Up, On-Surface-Synthesized Armchair Graphene Nanoribbons for Ultra-High-Power Micro-Supercapacitors

2020

Bottom-up-synthesized graphene nanoribbons (GNRs) with excellent electronic properties are promising materials for energy storage systems. Herein, we report bottom-up-synthesized GNR films employed as electrode materials for micro-supercapacitors (MSCs). The micro-device delivers an excellent volumetric capacitance and an ultra-high power density. The electrochemical performance of MSCs could be correlated with the charge carrier mobility within the differently employed GNRs, as determined by pump–probe terahertz spectroscopy studies.

Proximity Effects on the Charge Density Wave Order and Superconductivity in Single-Layer NbSe2

2021

Collective electronic states such as the charge density wave (CDW) order and superconductivity (SC) respond sensitively to external perturbations. Such sensitivity is dramatically enhanced in two dimensions (2D), where 2D materials hosting such electronic states are largely exposed to the environment. In this regard, the ineludible presence of supporting substrates triggers various proximity effects on 2D materials that may ultimately compromise the stability and properties of the electronic ground state. In this work, we investigate the impact of proximity effects on the CDW and superconducting states in single-layer (SL) NbSe2 on four substrates of diverse nature, namely, bilayer graphene…