6 results about "Hydrogen annealing" patented technology

This invention relates to a peak-valley confined catalyst structure and a method for preparing a highly oriented spinnable carbon nanotube array. The peak-valley confined catalyst structure comprises a silicon substrate covered with a silica layer, a lower alumina layer, a metal catalyst layer, and an upper alumina layer, stacked sequentially. The contact surface between the lower alumina layer and the metal catalyst layer has a continuous peak-valley structure. The upper alumina layer and the peak-valley morphology work together to restrict the movement and aggregation of the catalyst at high temperatures. Subsequently, carbon nanotube arrays are grown based on the peak-valley confined catalyst structure using a water-assisted chemical vapor deposition method. During this process, the introduction of water vapor effectively removes amorphous carbon from the substrate and the surface of the carbon nanotubes, ensuring high cleanliness of the catalyst and the carbon nanotube array. The high-temperature hydrogen annealing, combined with the peak-valley confined catalyst structure, ensures uniform catalyst particle size and distribution, resulting in a highly oriented spinnable carbon nanotube array.

This invention relates to the field of electrocatalytic materials technology, specifically to a NiW2-WO2 / NF composite electrocatalytic material, its preparation method, and its applications. This catalytic material is prepared using nickel foam as a substrate through hydrothermal synthesis and hydrogen annealing reduction, forming a three-dimensional tetrahedral porous structure of NiW2 alloy and WO2 composite. This catalytic material exhibits ultra-high active site density, ultra-low charge transfer resistance, and a superhydrophobic surface, achieving a resistance of 10 mA·cm⁻¹. ‑2 and 1000mA·cm ‑2 The overpotentials were 15mV and 280mV, respectively, and the Tafel slope was 41mV·dec. ‑1 And at 500mA·cm ‑2 It operated stably for 500 hours. In-situ infrared spectroscopy confirmed that it can dynamically regulate the interfacial water structure, with four-coordinated hydrogen-bonded water (4HB-H2O) accounting for 35%, which enhances the connectivity of the hydrogen bond network and effectively reduces the water dissociation energy barrier, making it suitable for industrial-grade high-current water electrolysis for hydrogen production.

This invention discloses a method for high-quality, clean electroslag ingot smelting in an oxygen-free, low-vacuum environment. It employs a multi-functional protective atmosphere vacuum pressurized electroslag furnace with upper and lower furnace chambers and a dedicated meshing device for sealing. This furnace offers excellent sealing and rapid evacuation, allowing the entire crystallizer to be placed in the lower chamber. The low vacuum prevents slag from being sucked up, ensuring a smooth electroslag remelting process, minimizing slag boiling, stabilizing the molten steel, and resulting in high-quality electroslag ingots. An oxygen detector is used to monitor the oxygen content within the furnace. Vacuuming is initiated when the oxygen content reaches 0 ppm to ensure an oxygen-free environment. Smelting at a vacuum level of 3000–5000 Pa ensures that the molten slag does not detach from the molten steel surface due to evacuation force, while also guaranteeing electroslag remelting under low vacuum conditions. Using refined slag as the furnace slag significantly reduces the formation of inclusions in the electroslag ingots and allows for the smelting of various high-quality, clean, special electroslag steels. Hydrogen diffusion annealing is used to remove hydrogen, ensuring that the hydrogen content in the electroslag ingot is ≤1.0 ppm.

This invention relates to a semiconductor thin film epitaxy method, comprising the following steps: (1) preparing an epitaxial substrate; (2) preparing an etched structure layer comprising a plurality of longitudinal etched structures on the surface of the epitaxial substrate; (3) preparing a porous structure layer below the etched structure layer; and (4) epitaxially growing a target semiconductor thin film above the etched structure layer. This invention incorporates an etched structure layer during the epitaxy process, where the unetched areas retain a smooth material surface, allowing direct use for the epitaxy of high-quality semiconductor thin films. This eliminates or reduces the need for post-processing requirements such as hydrogen annealing, significantly reducing process difficulty and cost.

The application provides a high-purity alumina substrate and a preparation method and application thereof, the preparation method adopts a pure 99.99% alumina system without additives, a green body is prepared through flow casting, and the green body is subjected to 1600-1700 DEG C air pre-sintering, 1800-1880 DEG C pure hydrogen final sintering, double-side precision grinding and polishing and 1550-1650 DEG C pure hydrogen annealing, and a high-purity alumina substrate with excellent comprehensive performance is prepared. Through the synergistic process of two-stage atmosphere sintering and polishing before annealing, grain uniform refinement and high densification are realized, the product has a bending strength of greater than or equal to 660 MPa, a Young's modulus of greater than or equal to 400 GPa, a thermal conductivity of greater than or equal to 29 W / (m*K), a surface roughness Ra of less than or equal to 2 nm, a warpage of less than or equal to 0.05%, and a visible light transmittance of 76%-86%. The substrate is particularly suitable for the field of advanced semiconductor packaging and has a wide industrial application prospect.

This invention relates to the preparation of an anode catalyst and a method for the highly selective electrocatalytic preparation of glycolates from ethylene glycol. The main challenge is addressing the low selectivity and insufficient conversion rates in current ethylene glycol electrocatalytic oxidation reactions. This invention employs a three-step method—hydrothermal-hydrogen annealing-impregnation—to prepare a Pd-NiCrO2 catalyst. The Pd-NiCrO2 catalyst exhibits strong activity, high selectivity, and good stability in the electrocatalytic oxidation of ethylene glycol, achieving a conversion rate of 100 mA / cm². 2 At the current density, the operating voltage is only 0.70 V; in addition, the chronocurrent stability of this anode catalyst can be maintained at more than 80% under different voltages, and the chronocurrent stability at 1.0 V can reach more than 91%.