摘要:
Methods for synthesizing aluminum-modified silazanes, their use as polymer-derived ceramic precursors, and polymer-derived ceramics and carbon nanotube core/shell nanocomposites formed therefrom are disclosed.
摘要:
The synthesis of layered freestanding papers composed of acid-functionalized, few-layer molybdenum disulfide (MoS2) and reduced graphene oxide (rGO) flakes for use as a binder-free conducting electrode in NIB applications are described. The mechanical and electrochemical performance of the layered freestanding papers is also described. Synthesis was achieved through vacuum filtration of highly homogenous dispersions comprising varying weight percentages of exfoliated MoS2 flakes in graphene oxide in DI water, followed by thermal reduction. The electrochemical behavior of the composite paper was evaluated as a counter electrode against pure Na foil in a half-cell configuration. In addition, the uniaxial tensile testing of the composite papers demonstrated their exceptionally high fracture strength.
摘要:
Polymer-derived ceramic composites are described herein. The composites are formed using hexagonal boron nitride nanosheet-functionalized silicon-based ceramic precursor polymers. The composites a matrix of a polymer-derived ceramic and hexagonal boron nitride nanosheets embedded therein. Silicon-derived ceramic precursors such as polysilazane and/or polysiloxane are used to create improved SiCN and/or SiOC ceramic composites.
摘要:
The synthesis of layered free-standing papers, films, tapes, and painted coatings. composed of acid-functionalized, few-layer molybdenum disulfide (MoS2) and reduced graphene oxide (rGO) flakes for use as a binder-free conducting electrode in NIB applications are described. The mechanical and electrochemical performance of the layered free-standing papers is also described. Synthesis was achieved through vacuum filtration of highly homogenous dispersions comprising varying weight percentages of exfoliated MoS2 flakes in graphene oxide in DI water, followed by thermal reduction. The electrochemical behavior of the composite paper was evaluated as a counter electrode against pure Na foil in a half-cell configuration. In addition, the unaxial tensile testing of the composite papers demonstrated their exceptionally high fracture strength.
摘要:
New methods for synthesizing boron-modified silazanes, their use as polymer-derived ceramic precursors, and polymer-derived ceramics and composites formed therefrom are disclosed. The polymeric ceramic precursors comprise a boron-modified silazane that is a room temperature liquid-phase polymer comprising a backbone having recurring monomeric repeat units comprising boron-nitrogen bonds. Nanocomposites comprising polymer-derived ceramics and carbon nanotubes are also disclosed.
摘要:
The synthesis of layered freestanding papers composed of acid-functionalized, few-layer molybdenum disulfide (MoS2) and reduced graphene oxide (rGO) flakes for use as a binder-free conducting electrode in NIB applications are described. The mechanical and electrochemical performance of the layered freestanding papers is also described. Synthesis was achieved through vacuum filtration of highly homogenous dispersions comprising varying weight percentages of exfoliated MoS2 flakes in graphene oxide in DI water, followed by thermal reduction. The electrochemical behavior of the composite paper was evaluated as a counter electrode against pure Na foil in a half-cell configuration. In addition, the unaxial tensile testing of the composite papers demonstrated their exceptionally high fracture strength.
摘要:
Polymer-derived ceramic composites are described herein. The composites are formed using hexagonal boron nitride nanosheet-functionalized silicon-based ceramic precursor polymers. The composites a matrix of a polymer-derived ceramic and hexagonal boron nitride nanosheets embedded therein. Silicon-derived ceramic precursors such as polysilazane and/or polysiloxane are used to create improved SiCN and/or SiOC ceramic composites.
摘要:
Methods for synthesizing aluminum-modified silazanes, their use as polymer-derived ceramic precursors, and polymer-derived ceramics and carbon nanotube core/shell nanocomposites formed therefrom are disclosed.
摘要:
A composite material comprising graphene or reduced graphene oxide and a polymer-derived ceramic material, such as SiOC, is provided. The composite materials can be used to construct anodes (16), which can be used in batteries (10), particularly lithium ion batteries. The anodes exhibit relatively high charge capacities at various current densities. Moreover, the charge capacity of the anodes appears exceptionally stable even after numerous charging cycles, even at high current densities.
摘要:
Ceramic matrix composite (CMC) materials are a desired solution for lightweight and high temperature applications. CMC materials can be reinforced with polymer-derived ceramic (PDC) fibers, which advantageously possess intrinsic thermal stability and high mechanical strength. Carbon-rich SiOC and SiOCN fibers were synthesized via hand-drawing and electrospinning polymer pyrolysis of a hybrid precursor materials with the aid of a spinning reagent. The prepared fibers are crosslinked and pyrolyzed for polymer-to-ceramic conversion.