Graphene-like Carbon from Calcium Hydroxide

Abstract

The development of inexpensive and environmentally friendly graphene-like carbon is critical for its integration into industrial products. This work highlights the production of graphene-like carbon structures from calcium hydroxide. The chemical vapor deposition conditions to grow graphitic carbon on a calcium hydroxide catalyst are reported. Acetylene, steam, and calcium hydroxide are used to grow a crumpled carbon morphology. The crumpled carbon resulted in a high surface area of 1276 m 2 /g and high electrical conductivity (>10 5 S/m). Additionally, the significance and origin of the C 1s X-ray photoelectron spectroscopy (XPS) π−π* plasmon loss peak as it is related to high electrical conductivity is reported. A unique mechanism for the catalytic process involving calcium acetylide is proposed. Several deposition times, steam concentration, and catalyst morphology were tested to synthesize a variety of carbon morphologies from calcium-based materials. Crumpled carbon, hollow nanospheres, bamboo-like carbon nanotubes, multi-walled carbon nanotubes, and graphene fiber morphologies were all formed using calcium-based catalysts. Multiple reaction conditions, a scaled reaction (300 g), and catalyst recyclability were investigated. Calcium-based materials were then used as catalysts for the growth of other graphene-like carbons.

Constructing Charge Bridge Path for High‐Performance Tin Perovskite Photovoltaics

“…The 3‐AMBTh treatment also caused changes in the C 1 s core levels, which are displayed qualitatively in Figure 1c; The emergence of the π–π* satellite peak stems from the interaction between an ejected core‐shell carbon 1s electron and the delocalized π‐system. [ 25 ] In the pure ICBA sample, the peak area ratio corresponding to the π–π interaction region relative to the total area is determined to be 4.27%. This mainly originates from the π–π interactions present in pure ICBA samples.…”

Two-Dimensional Hexagonal-Shaped Mesoporous Carbon Sheets for Supercapacitors

“…Based on previous studies, − a mechanism for this reaction is proposed below Equation shows that the oxygen in MgO reacts with acetylene to form CO, leaving the magnesium to form a carbide. When the steam was supplied, magnesium acetylide was hydrolyzed to Mg­(OH) 2 and acetylene anions C 2– .…”

“…Two-dimensional (2D) mesoporous carbons may have shorter channels for charge transport, , which would be highly desirable for EDLCs. Mesoporous carbon materials have been obtained via a variety of methods including templating, which may produce ordered mesopores with narrow pore size distribution. , Recently, we established a templating process that involves metal carbide (LaC 2 , CaC 2 , YC 2 ) intermediates to form graphitic carbon. − At temperatures above 500 °C, carbon is formed by passing steam and acetylene gas over the metal carbide. Hydrolyzable carbides have been known since 1837 .…”

Magnesium Hydroxide Templated Hierarchical Porous Carbon Nanosheets as Electrodes for High-Energy-Density Supercapacitors

“…Recently, we prepared carbon on La­(OH) 3 , Y­(OH) 3 , and Ca­(OH) 2 nanoparticles using acetylene and steam. ,, Acetylene reacts with the metal hydroxide to develop a metal acetylide, which transforms back to metal hydroxide and acetylide anions through a reaction with steam. This leads to the growth of graphitic carbon.…”