Low temperature growth of pyrolytic carbon with well-ordered graphite structure by chemical vapour deposition methods

Yoshimoto, Yoshikazu; Suzuki, Tomonari; Higashigaki, Yoshiyuki; Nakajima, Shin

doi:10.1016/0040-6090(88)90215-5

Cited by 14 publications

(5 citation statements)

References 9 publications

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“…Evoking Woodward−Hoffmann rules for the conservation of orbital symmetry, deposition kinetics should occur more rapidly for benzene than for aliphatic hydrocarbons of lesser symmetry. Adding to this, it was observed that fibers grown from benzene were more graphitic in cross-section than their aliphatic counterparts, supporting previous reports that highly oriented graphite is obtained during the CVD of benzene . Finally, the benzene molecule has the highest ratio of carbon mass to molecular mass (C x H x ) of all the precursors in question, so that under identical pressures it will transport carbon more rapidly than any aliphatic molecule of identical χ-value.…”

Section: Resultssupporting

confidence: 83%

Hyperbaric Laser Chemical Vapor Deposition of Carbon Fibers from the 1-Alkenes, 1-Alkynes, and Benzene

et al. 2006

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The growth of long carbon fibers was investigated using hyperbaric-pressure laser chemical vapor deposition (HP-LCVD). Precursors included the unbranched alkenes with linear structure 1-C(x)H(2x) (where x = 2,4,5,6,7,8), the unbranched alkynes, i.e., 1-C(x)H(2)(x-2) (where x = 3,4,5,6,8), and benzene. Rate constants, reaction orders, and apparent activation energies were derived for each precursor over a range of experimental conditions. Axial growth rates from the alkenes were 1-2 orders of magnitude greater than for the alkynes, while growth rates for benzene exceeded 10 mm s(-1). Generalized expressions for the growth rate vs molecular weight were determined. For the alkenes, the growth rate was directly proportional to the square root of the precursor molecular weight, while the alkynes exhibited an inverse relationship. Two regions of differing reaction order were identified for the alkynes; at pressures less than 2.0-2.5 bar, the average reaction order was 3.07, while above 2.0-2.5 bar, reaction orders diverged. Expressions were derived for the fraction of carbon atoms deposited per alkyne molecule transported; the deposition efficiency decreased with molecular weight for the alkynes, due in part to the Soret effect. In contrast, the reaction order for the alkenes was 1.65, and for benzene was 2.25. A phase change in the deposit was observed for both the alkenes and alkynes, with the exceptions of pentene and pentyne. Complete axial rate equations for the alkenes and alkynes were derived, as well as volumetric growth equations for the alkynes. It was shown that the volumetric rate increases nonlinearly with laser power at sufficiently high pressures.

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Section: Resultssupporting

confidence: 83%

Hyperbaric Laser Chemical Vapor Deposition of Carbon Fibers from the 1-Alkenes, 1-Alkynes, and Benzene

et al. 2006

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“…Thin films of “pyrolytic carbon” (pyC) are readily generated by chemical vapor deposition at moderate pyrolysis temperatures (900–1300 °C) . Among the various hydrocarbon precursors that have been used, benzene is a convenient source for bench‐scale deposition and yields high‐quality pyC films . We recently reported on the use of benzene‐derived pyC films on planar fused‐silica substrates as a means to investigate heterogeneous electron transfer of redox probes.…”

Section: Introductionmentioning

confidence: 99%

“…[39,40] Among the various hydrocarbon precursors that have been used, benzene is a convenient source for bench-scale deposition and yields high-quality pyC films. [41][42][43][44][45] We recently reported on the use of benzene-derived pyC films on planar fused-silica substrates as a means to investigate heterogeneous electron transfer of redox probes. When modified by electrolessly depositing nanoparticulate ruthenium oxide, the RuOx-decorated pyC mimicked the fast rates of Pt, not the far slower rates of carbon.…”

Section: Introductionmentioning

confidence: 99%

Pyrolytic Carbon Films with Tunable Electronic Structure and Surface Functionality: A Planar Stand‐In for Electroanalysis of Energy‐Relevant Reactions

Parker

Sassin

et al. 2020

ChemElectroChem

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Fundamental charge‐transfer dynamics for technologically relevant carbons, such as disordered “hard” carbons, can be studied by designing planar mimics. We fabricate thin films of “pyrolytic carbon” (pyC) by decomposition of benzene at 1000 °C and examine the physical and electrochemical properties of the native pyC film, as well as variants after heteroatom doping, plasma oxidation, and metal nanoparticle modification. The pyC films are optically reflective at the macroscale, relatively planar (1–3 nm RMS roughness by atomic force microscopy) and disordered (via Raman scattering). Thiophenyl‐doped pyC films (0.6–1.7 atom % sulfur) suitably mimic the disorder, chemical state (X‐ray photoelectron spectroscopy), and work function (Kelvin probe) of a workhorse carbon black, Vulcan XC‐72. Using ferri/ferrocyanide as a redox probe, we find that oxygen functionalities enhance the heterogeneous electron‐transfer rate constant up to 3×, while high levels of sulfur dopants decrease the rate 2×. We also explore thiophenyl‐directed adsorption of Au nanoparticles and show that hydrogen evolution at 0.1 mA cm−2 occurs ∼95 mV more positive at <1 % Au@pyC∼S than at pyC∼S.

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“…24 In the present report, we explore the use of this nanometric RuOx surface modifier as a means to enhance the typically modest electron-transfer rates of carbon electrodes. The pyrolysis of benzene vapor at moderate temperatures (1000 °C) provides a simple chemical vapor deposition (CVD) route to disordered (or partially graphitized) carbon coatings on either planar substrates 32,33 or complex 3D objects. 34,35 We use such pyrolytic carbon films, deposited on fused silica plates, as effective 2D mimics of the disordered carbons (e.g., carbon black powders) that are commonly used in electrochemical applications.…”

Section: ■ Introductionmentioning

confidence: 99%

“…In the present report, we explore the use of this nanometric RuO x surface modifier as a means to enhance the typically modest electron-transfer rates of carbon electrodes. The pyrolysis of benzene vapor at moderate temperatures (1000 °C) provides a simple chemical vapor deposition (CVD) route to disordered (or partially graphitized) carbon coatings on either planar substrates , or complex 3D objects. , We use such pyrolytic carbon films, deposited on fused silica plates, as effective 2D mimics of the disordered carbons (e.g., carbon black powders) that are commonly used in electrochemical applications . The “CVD-C” substrates are coated electrolessly with RuO x using the solution-phase protocol noted above and the resulting RuO x @CVD-C assembly is calcined at 150, 200, and 250 °C to gradually convert the amorphous as-deposited RuO x to more ordered, rutile-like and ultimately nanocrystalline RuO 2 without initiating oxide-catalyzed combustion of the carbon …”

Section: Introductionmentioning

confidence: 99%

Rewriting Electron-Transfer Kinetics at Pyrolytic Carbon Electrodes Decorated with Nanometric Ruthenium Oxide

et al. 2017

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Platinum is state-of-the-art for fast electron transfer whereas carbon electrodes, which have semimetal electronic character, typically exhibit slow electron-transfer kinetics. But when we turn to practical electrochemical devices, we turn to carbon. To move energy devices and electro(bio)analytical measurements to a new performance curve requires improved electron-transfer rates at carbon. We approach this challenge with electroless deposition of disordered, nanoscopic anhydrous ruthenium oxide at pyrolytic carbon prepared by thermal decomposition of benzene (RuOx@CVD-C). We assessed traditionally fast, chloride-assisted ([Fe(CN)]) and notoriously slow ([Fe(HO)]) electron-transfer redox probes at CVD-C and RuOx@CVD-C electrodes and calculated standard heterogeneous rate constants as a function of heat treatment to crystallize the disordered RuOx domains to their rutile form. For the fast electron-transfer probe, [Fe(CN)], the rate increases by 34× over CVD-C once the RuOx is calcined to form crystalline rutile RuO. For the classically outer-sphere [Fe(HO)], electron-transfer rates increase by an even greater degree over CVD-C (55×). The standard heterogeneous rate constant for each probe approaches that observed at Pt but does so using only minimal loadings of RuOx.

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Low temperature growth of pyrolytic carbon with well-ordered graphite structure by chemical vapour deposition methods

Cited by 14 publications

References 9 publications

Hyperbaric Laser Chemical Vapor Deposition of Carbon Fibers from the 1-Alkenes, 1-Alkynes, and Benzene

Hyperbaric Laser Chemical Vapor Deposition of Carbon Fibers from the 1-Alkenes, 1-Alkynes, and Benzene

Pyrolytic Carbon Films with Tunable Electronic Structure and Surface Functionality: A Planar Stand‐In for Electroanalysis of Energy‐Relevant Reactions

Rewriting Electron-Transfer Kinetics at Pyrolytic Carbon Electrodes Decorated with Nanometric Ruthenium Oxide

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