Graphene-reinforced silicon oxycarbide composites prepared by phase transfer

Yu, Min; Picot, Olivier T.; Saunders, Theo; Dlouhý, Ivo; Feng, Jinyu; Titirici, Maria‐Magdalena; Mahajan, Amit; Reece, Michael J.

doi:10.1016/j.carbon.2018.07.042

Cited by 16 publications

(13 citation statements)

References 38 publications

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“…and NGA-SiOC100, respectively, which are several orders of magnitude higher than those of pristine SiOC following pyrolysis at the same temperatures 59 and are of a similar magnitude to the conductivity of pure graphene aerogels [60][61] . Compared with other reported graphene/PDC composites summarised in Table S1 (SiOC-graphene@1500/1700 50 , SiOC-GO@1700 47 , RGO/CNTS/SiCN@1000 26 , GO/PSZ@800/1000 51 , SiCN-rGO@1000 46 , SiCNO-GO@1000 48 , SiCO/GO@1100 62 , rGO/Si3N4@1600 63 , SiCN/rGOA@1000 49 ), the lightweight, porous properties of the 3D porous NGA-SiOC monoliths (NGA-SiOC15, NGA-SiOC50 and NGA-SiOC100) and the reported graphene/PDCs (SiOC-graphene@1500/1700 50 , SiOC-GO@1700 47 , RGO/CNTS/SiCN@1000 26 , GO/PSZ@800/1000 51 , SiCN-rGO@1000 46 , SiCNO-GO@1000 48 , SiCO/GO@1100 62 , rGO/Si3N4@1600 63 , SiCN/rGOA@1000 49 ) (e) Schematic of the conductive pathway for electron transport in porous graphene/SiOC monoliths and dense random graphene/SiOC composite. (Note: The unreported density of dense composites is defined as 2g/cm 3 in (d)).…”

Section: Resultsmentioning

confidence: 89%

Polymer-Derived SiOC Integrated with a Graphene Aerogel As a Highly Stable Li-Ion Battery Anode

Shao

Hanaor

Wang

et al. 2020

ACS Appl. Mater. Interfaces

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Amorphous polymer-derived silicon oxycarbide (SiOC) is an attractive candidate for Li-ion battery anodes, as an alternative to graphite, which is limited to a theoretical capacity of 372 mAh/g. However, SiOC tends to exhibit poor transport properties and cycling performance as the result of sparsely distributed carbon clusters and inefficient active sites. To overcome these limitations, we designed and fabricated a layered graphene/SiOC heterostructure by solvent assisted infiltration of a polymeric precursor into a modified 3D graphene aerogel skeleton. The use of a high-melting-point solvent facilitated the precursor's freeze-drying, which following pyrolysis yielded SiOC as a layer supported on the surface of nitrogen doped reduced graphene oxide aerogels. The fabrication method employed here modifies the composition and microstructure of the SiOC phase. Among the studied materials, highest levels of performance were obtained for a sample of moderate SiOC content, in which the graphene network constituted 19.8wt% of the system. In these materials a stable reversible charge capacity of 751 mAh/g was achieved at low charge rates. At high charge rates of 1480 mA/g the capacity retention was ~95% (352 mAh/g) after 1000 consecutive cycles. At all rates, Colombic efficiencies >99% were maintained following the first cycle. Performance across all indicators was majorly improved in the graphene aerogel/SiOC nanocomposites, compared with unsupported SiOC. Performance was attributed to mechanisms across multiple lengthscales. The presence of oxygen rich SiO4−xCx tetrahedra units and a continuous free-carbon network within the SiOC provide sites for reversible lithiation, while high ionic and electronic transport is provided by the layered graphene/SiOC heterostructure.

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Section: Resultsmentioning

confidence: 89%

Polymer-Derived SiOC Integrated with a Graphene Aerogel As a Highly Stable Li-Ion Battery Anode

Shao

Hanaor

Wang

et al. 2020

ACS Appl. Mater. Interfaces

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“…An increase in I G / I D intensity ratio observed for PDC with the addition of Ni, Co, Ni–Pt, and Co–Pt confirms the presence of curved and closed graphitic structures in nanotubes forms . In addition, the strong appearance of a 2D peak at ∼2673 cm –1 for Ni, Co, Ni–Pt, and Co–Pt containing ceramics shows the existence of graphene layer confirming the higher degree of CNT formation. − …”

Section: Results and Discussionmentioning

confidence: 74%

Metal-Containing Ceramic Composite with in Situ Grown Carbon Nanotube as a Cathode Catalyst for Anion Exchange Membrane Fuel Cell and Rechargeable Zinc–Air Battery

Prabu

Pollachini

Wilhelm

et al. 2019

ACS Appl. Energy Mater.

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The development of new air-breathing cathode catalyst not only addresses the performance of fuel cells and metal−air batteries but also make them cheaper. Herein, we developed a new, metal containing (Ni, Co, Pt and their alloys) ceramic composite as a cathode electrocatalyst for anion exchange membrane fuel cell (AEMFC) and zinc−air battery (ZAB) application. The porous ceramic foams were generated with the help of a sacrificial template method in which polystyrene beads were infiltrated with a polysiloxane precursor. With addition of metal salts into the porous ceramic matrix, the formation of carbon nanotubes (CNTs) by applying catalyst-assisted pyrolysis was facilitated. The in situ grown CNTs in composite ceramic affect the charge transport and drastically improved the electrical conductivity of up to 6 orders in magnitude compared with the bare ceramics (H.A). The best performing Ni-containing ceramics (H.A.Ni) show improved oxygen reduction activity in half-cell measurements and for AEMFC delivered an open-circuit voltage of 0.65 V with a maximum power density of ∼10 mW cm −2 . In rechargeable ZAB systems, the H.A.Ni showed excellent battery performance with a specific capacitance of 490 mAh g −1 , maximum power density of 110 mW cm −2 , and excellent discharge/charge cycle stability over 300 cycles. Results indicate that the presence of CNT and intermetallic silicides such as Ni 2 Si and Ni 31 Si 12 tunes the electrical properties and enhances the electrocatalytic activity toward oxygen. Thus, the Ni-containing ceramic material is as an excellent cathode catalyst for AEMFC and rechargeable ZAB applications.

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“…Moreover, the microstructure (grain size, thickness, and crystallinity of grain boundaries) [ 17 , 18 , 19 ], the concentration of impurity atoms including lattice oxygen in matrix grains [ 17 , 19 , 20 ], and the conditions of additional heat treatment after sintering [ 6 , 21 ] also affect the functional properties of ceramic–graphene composites. The enhancement of electrical conductivity of ceramic–graphene composites in both in-plane and cross-plane directions is more straightforward than in the case of thermal conductivity, as was confirmed by many studies [ 2 , 6 , 7 , 8 , 9 , 11 , 12 , 22 ]. Electrical conductivity usually increases with an increasing amount of graphene nanoplatelets in both directions.…”

Section: Introductionmentioning

confidence: 64%

Preparation and Properties of Layered SiC-Graphene Composites for EDM

et al. 2021

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Three and five-layered silicon carbide-based composites containing 0, 5, and 15 wt.% of graphene nanoplatelets (GNPs) were prepared with the aim to obtain a sufficiently high electrical conductivity in the surface layer suitable for electric discharge machining (EDM). The layer sequence in the asymmetric three-layered composites was SiC/SiC-5GNPs/SiC-15GNPs, while in the symmetric five-layered composite, the order of layers was SiC-15GNPs/SiC-5GNPs/SiC/SiC-5GNPs/SiC-15GNPs. The layered samples were prepared by rapid hot-pressing (RHP) applying various pressures, and it was shown that for the preparation of dense 3- or 5-layered SiC/GNPs composites, at least 30 MPa of the applied load was required during sintering. The electrical conductivity of 3-layered and 5-layered composites increased significantly with increasing sintering pressure when measured on the SiC surface layer containing 15 wt.% of GNPs. The increasing GNPs content had a positive influence on the electrical conductivity of individual layers, while their instrumented hardness and elastic modulus decreased. The scratch tests confirmed that the materials consisted of well-defined layers with straight interfaces without any delamination, which suggests good adhesion between the individual layers.

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Graphene-reinforced silicon oxycarbide composites prepared by phase transfer

Cited by 16 publications

References 38 publications

Polymer-Derived SiOC Integrated with a Graphene Aerogel As a Highly Stable Li-Ion Battery Anode

Polymer-Derived SiOC Integrated with a Graphene Aerogel As a Highly Stable Li-Ion Battery Anode

Metal-Containing Ceramic Composite with in Situ Grown Carbon Nanotube as a Cathode Catalyst for Anion Exchange Membrane Fuel Cell and Rechargeable Zinc–Air Battery

Preparation and Properties of Layered SiC-Graphene Composites for EDM

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