7 results about "Porous morphology" patented technology

This application provides a high specific surface area, high tap density small-particle ternary precursor, its preparation method, cathode material, and lithium-ion battery, relating to the field of lithium-ion batteries. It includes a core and a first coating layer and a second coating layer sequentially disposed on the surface of the core; the core is a secondary particle formed by the stacking of multiple primary particles; the first and second coating layers are each independently formed by alternating layers of sheet-like primary particles; the sheet-like primary particles of the first coating layer are shorter than those of the second coating layer. The high specific surface area, high tap density small-particle ternary precursor exhibits a porous morphology with a loose interior and a relatively dense exterior, increasing porosity and specific surface area. Simultaneously, the relatively dense surface structure improves the tap density of the precursor. This morphology, when sintered into a cathode material, is beneficial for lithium-ion electron transport.

The invention discloses a ZnO (at) C-ZIF composite gas sensitive material and a preparation method and application thereof.The ZnO (at) C-ZIF composite gas sensitive material is characterized in that ZnO (at) ZIF-8 is synthesized through a simple hydrothermal method, then the ZnO (at) ZIF-8 is used as a substrate and subjected to heat treatment in the Ar atmosphere, the ZIF-8 is pyrolyzed to form a carbonaceous layer, the carbonaceous layer tightly covers the surface of ZnO, and the ZnO (at) C-ZIF composite gas sensitive material is formed. The heat treatment temperature of C-ZIF is low, part of a ZIF-8 frame is kept, the exposed and protruding C-ZIF structure presents a layered porous morphology, the C-ZIF can be effectively used as a supporting layer between ZnO nanosheets, aggregation and self-accumulation of the ZnO nanosheets are prevented, and therefore more active sites are provided. The C-ZIF covers the surface of ZnO to enhance the moisture resistance of the composite material, and the structure is helpful for adsorbing and screening gas molecules, and can also form a heterojunction with ZnO to promote the transmission of charge carriers and improve the sensitivity to ethanol gas. The prepared ZnO-coated C-ZIF material has the advantages of low working temperature, high sensitivity, high stability and excellent moisture resistance, meets actual requirements, and has good environmental compatibility.

The application provides a silicon-on-insulator structure and a forming method thereof, and the forming method of the silicon-on-insulator structure increases the room-temperature bonding strength during a bonding process through an activation treatment, reduces the temperature required in a subsequent reinforcement process, thereby reducing the thermal diffusion of heterogeneous components in the etching stop layer, ensuring the clear interface between the etching stop layer and a device layer, and further avoiding the deterioration of the thickness uniformity of the device layer after the etching stop layer is removed in the subsequent process; the uniformity of the device layer after etching is controlled through two selective etching processes, so that the thickness uniformity of the device layer of the finally obtained silicon-on-insulator structure is less than 10%; and the formation and removal of a sacrificial oxide layer make the surface of the device layer not have a porous morphology of high-frequency etching undulation.

This invention provides a porous cathode precursor, a composite cathode material, its preparation method, and its application. The preparation method of the porous cathode precursor includes the following steps: co-precipitating a ternary mixed metal salt solution, a complexing agent solution containing citrate, a precipitant solution, and an oxidant solution into a reaction substrate to obtain a half-step precursor material; and pre-sintering the half-step precursor material to obtain the porous cathode precursor. The cathode precursor prepared by the method provided by this invention has a hollow porous morphology, which is beneficial for improving the cycle performance and rate performance of the ternary cathode material.

The invention provides a high-specific-surface-area high-tap-density small-particle ternary precursor, a preparation method thereof, a positive electrode material and a lithium ion battery, and relates to the field of lithium ion batteries. Comprising an inner core, and a first coating layer and a second coating layer which are sequentially arranged on the surface of the inner core, the inner core is a secondary particle formed by stacking a plurality of primary particles; the first coating layer and the second coating layer are respectively and independently formed by staggered arrangement of flaky primary particles; the sheet-like primary particles of the first coating layer are shorter than the sheet-like primary particles of the second coating layer. The high-specific-surface-area high-tap-density small-particle ternary precursor has a porous morphology which is loose inside and dense outside, the porosity and the specific surface area are increased, meanwhile, the tap density of the precursor is improved through the structure with the relatively dense surface, and lithium electron transmission is facilitated after the precursor is sintered into a positive electrode material through the morphology.

The invention provides a WO3-gamma film based on periodic alternate oxygen supply three-path coordinated regulation and a preparation method and application thereof. According to the preparation method, periodic alternate regulation of oxygen flow is implemented in the magnetron sputtering process, so that three-path coordinated regulation of oxygen vacancies, porous morphology and an amorphous / nanocrystalline coexisting structure in the WO3 film is realized, and the electrochromic response rate and cycling stability of the film in an aqueous electrolyte are remarkably improved. The prepared WO3-gamma film has more than 70% of optical modulation amplitude, the coloring / fading response time is less than 0.03 second, and the CV curve area is still kept more than 97% after 500 cycles. The composite material has excellent electrochemical performance, structural stability and environmental friendliness, and can be widely applied to the fields of water system intelligent windows, electrochromic display, wearable devices and the like.

The invention relates to the technical field of flexible piezoelectric sensor preparation, and particularly discloses a flexible piezoelectric sensor based on porous microstructure PDMS and a preparation method thereof, and the preparation method comprises the following steps: S1, preparing an organic-inorganic composite cured body; s2, obtaining a solidified block containing a uniformly dispersed sucrose template inside; s3, obtaining the PDMS sponge with the communicated porous microstructure; s4, obtaining a dry sponge with a porous morphology; s5, obtaining a precursor film covering body; and S6, obtaining the porous microstructure ZnO / PDMS composite membrane. S7, forming flexible upper and lower electrode layers; and S8, completing device packaging and obtaining the flexible piezoelectric sensor. Interconnected pore channels are introduced into a PDMS matrix through a sucrose template method, so that the overall specific surface area of the material is remarkably increased, and piezoelectric active ZnO nanowire networks are grown in situ in pore walls, so that external pressure can excite piezoelectric polarization response in a larger range and a deeper level; therefore, the conversion efficiency of the mechanical stress to the electric signal is enhanced.