5 results about "Defective graphene" patented technology

This invention relates to the field of functional materials technology, and particularly to a floating defective g-C3N4 / PDI composite thin-film photocatalyst, its preparation method, and its application. The preparation method of the floating defective g-C3N4 / PDI composite thin-film photocatalyst provided by this invention includes the following steps: mixing defective graphene carbon nitride, N,N'-bis(3-aminopropyl)perylene-3,4,9,10-tetracarboxylic acid diimide (PDI), an organic base, and water to obtain a first suspension; mixing the first suspension with a monohaloacetic acid to undergo a protonation reaction, followed by solid-liquid separation to obtain a protonated composite material; mixing the protonated composite material with a thermoplastic resin solution to obtain a second suspension; and forming the second suspension into a film and then drying it to obtain the floating defective g-C3N4 / PDI composite thin-film photocatalyst. This photocatalyst is recyclable after use, does not cause secondary pollution to the environment, and exhibits excellent photocatalytic performance.

This invention discloses a defective graphene-reinforced battery composite electrode and its preparation method, comprising a current collector, a defective graphene conductive coating, and an electrode active material layer; the defective graphene conductive coating is disposed on both sides of the current collector; the electrode active material layer is coated on the defective graphene conductive coating on both sides or on one side; and / or the electrode active material layer is doped with defective graphene nanosheets, or the composite electrode is in the form of a self-supporting electrode, composed of multilayer stacked defective graphene conductive films, the films containing nanopores and defect sites. This invention fully utilizes the high chemical activity of graphene defect sites, enabling it to have the triple functions of conductive additive, bonding bridge, and active lithium storage medium, synergistically optimizing the electrode microstructure and interface performance.

The application discloses a controllable preparation method of a graphene film containing topological structure defects, and comprises the following steps: selecting a carbon source precursor molecule containing one or more non-six-membered ring topological structure units in a molecular skeleton; placing a metal substrate in a reaction furnace and heating to a growth temperature; introducing the vaporized carbon source precursor molecule into the reaction furnace from a carrier gas, pyrolyzing, nucleating and growing a graphene film on the surface of the metal substrate, and in-situ retaining the non-six-membered ring topological structure units in a graphene lattice to form topological defects; controlling the density and distribution of the topological defects; and obtaining the defective graphene film after cooling. The application realizes the engineering controllable regulation of the defect density of graphene on a macroscopic scale, is the first in the field of molecular template guided graphene defect engineering, and can be used for preparing graphene functional materials with on-demand designed performance, and has a wide application prospect in the fields of sensing, catalysis, energy storage and electronic devices.

This invention discloses a method for on / off modulation of the hydrogen evolution reaction (HER) by defect-induced ferroelectric-antiferroelectric transition in graphene and its application. The method constructs a bilayer system of defective graphene (D-graphene) containing g-C₃N₄-like vacancy pores and g-C₃N₄ layers, with the layers coupled by van der Waals forces. A reversible ferroelectric-antiferroelectric phase transition is achieved through interlayer slip, and the HER is precisely modulated using changes in polarization intensity and direction. The defective graphene bilayer can form an ON-OFF ferroelectric switch, with the Gibbs free energy ΔG for ferroelectric hydrogen adsorption. H * Approaching the optimal value, the catalysis is in the on state; however, excessive hydrogen adsorption in the antiferroelectric state leads to catalysis shutdown. The g-C₃N₄ bilayer can achieve three-level regulation (ON-OFF-ON) through ferroelectric-paraelectric-ferroelectric polarization switching, with the ferroelectric polarization state significantly enhancing HER activity. This invention is free of precious metals, has a low interlayer sliding barrier, and exhibits catalytic performance comparable to platinum-based catalysts. It provides a new strategy for the design of highly efficient intelligent electrocatalysts and novel catalytic switching devices, and has significant application value in the field of clean energy.

This invention relates to the field of catalysts for the hydrogenation of nitrobenzene to aniline, specifically disclosing a magnetically separable carbon-supported platinum cluster catalyst, its preparation method, and its applications. The magnetically separable carbon-supported platinum cluster catalyst comprises platinum nanoparticles as the active component and a nickel-coated nitrogen-doped graphene composite material as the support. The nickel-coated nitrogen-doped graphene composite material has a core-shell structure, with platinum nanoparticles uniformly loaded in clusters on the surface of the nitrogen-doped graphene, bonding with carbon and nitrogen atoms on graphene defects. The high utilization rate of platinum atoms enables efficient hydrogenation of nitrobenzene even at low loading levels, while also making the catalyst structure more stable. The support surface has abundant carbon defects and oxygen-containing functional groups, which facilitates the anchoring of platinum nanoparticles to the support surface through strong interactions between the metal and the support. The magnetic nickel nanoparticles impart a certain degree of magnetism to the catalyst, allowing for dispersion and recovery of the catalyst simply by removing and applying a magnetic field.