The disclosure provides a preparation method for a graphene material-based resistive gas sensor array and an application method thereof. The preparation method includes: adding a metal salt solution to a graphene oxide solution to obtain a mixed suspension, adjusting a pH of the mixed suspension and dispersing the mixed suspension under ultrasound, incubating the mixed suspension on a shaker, then washing it with deionized water followed by dispersing it in a deionized water to obtain metal ion-induced graphene oxide self-assembled suspension, and preparing a plurality of parts of the suspension by varying the preparation conditions; and adding the plurality of parts of metal ion-induced graphene oxide self-assembled suspension respectively to fingers of a multi-site interdigitated electrode array, and drying naturally, reducing the plurality of parts of the suspension at 60 to 120° C. for 3 to 30 min. The disclosure achieves uniform loading of a graphene material on a substrate.

An electrode material, its manufacturing method, and its use as a cathode material in batteries are provided. The electrode material comprises a plurality of nanoparticles, each having a diameter of approximately 100-400 nm and comprising a core and a shell encapsulating the core. The shell comprises carbon and nitrogen, respectively having a mass fraction of approximately 70-90% and approximately 5-20% relative to a total mass of the shell. The core comprises sulfur, having a mass fraction of approximately 40-97% relative to a total mass of the core. The core has a mass fraction of approximately 50-90% relative to a total mass of each nanoparticle. The electrode material can be used in a cathode of a Li—S battery, which has a good energy storage capacity, a high electrochemical stability, and a low capacity decay.

The present disclosure relates to a positive electrode active material, a method of preparing the same, and a lithium secondary battery having a positive electrode including the same. The positive electrode active material includes: a lithium transition metal oxide particle in which a portion of Li is substituted with Na, and which includes Ni and Co atoms, wherein the lithium transition metal oxide particle includes a concentration gradient region in which the concentration of Co atoms decreases from the surface toward the center of the particle.

The present disclosure discloses a W-containing high-nickel ternary cathode material, including both spherical secondary particles and single-crystal particles. There is basically no W inside the single-crystal particles, and the spherical secondary particles are doped with W. A preparation method of the W-containing high-nickel ternary cathode material includes: mixing a nickel salt, a cobalt salt, and a manganese salt according to a specified molar ratio, and adding an ammonia solution and a sodium hydroxide solution for co-precipitation to prepare a precursor A; mixing a nickel salt, a cobalt salt, a manganese salt, and a tungsten salt, and adding an ammonia solution and a sodium hydroxide solution for co-precipitation to prepare a W-containing precursor B; and mixing the precursor A, the precursor B, a lithium source, and a doping element M-containing compound, and subjecting a resulting mixture to high-temperature sintering in an oxygen atmosphere to obtain the high-nickel ternary cathode material including both spherical secondary particles and single-crystal particles. While increasing the capacity, the spherical secondary particles in the product of the present disclosure can ensure that a crystal structure will not undergo obvious phase transition when lithium ions are deintercalated during a cycling process, which helps to improve the cycling performance.

This invention relates to a process for treating acid mine drainage (AMD). The process includes the steps of adjusting the pH of the AMD to be in the range of 3 to 5; adding maghemite nanoparticles to form a slurry; and a) aerating the slurry obtained in step 3), or b) simultaneously heating and mixing the slurry obtained in step 3). Thereafter maghemite nanoparticles loaded with one or more metals and sulphate and precipitated metals is separated from the slurry.

The present invention relates to a positive electrode active material comprising an overlithiated layered oxide (OLO) and, more specifically, to a positive electrode active material comprising: an OLO represented by chemical formula 1 below; and an amorphous free oxide coating layer of an amorphous free oxide on the surface of the OLO represented by chemical formula 1. [Chemical formula 1] Li.sub.2MnO.sub.3.(1-r)Li.sub.aNi.sub.xCo.sub.yMn.sub.zM1.sub.1-(x+y+z)O.sub.2 (wherein, in chemical formula 1, 0<r≤0.6, 0<a≤1, 0≤x≤1, 0≤y<1, 0≤z<1, and 0<x+y+z≤1, and M1 is at least any one selected from Na, K, Mg, Al, Fe, Cr, Y, Sn, Ti, B, P, Zr, Ru, Nb, W, Ba, Sr, La, Ga, Mg, Gd, Sm, Ca, Ce, Fe, Al, Ta, Mo, Sc, V, Zn, Cu, In, S, B, Ge, Si, and Bi).

Slug flow manufacturing systems and methods for production of battery microparticle materials such as nickel-cobalt-manganese oxide (NCM) are disclosed. The slug flow reactor system is capable of producing microparticles reproducibly and continuously in desired scales. The system may be run with fast kinetics (e.g., complete reaction from nucleation to particle recovery completes within a few minutes) and near-ambient reaction temperature (e.g., allowing to use inexpensive plastic tubing). The system allows control of composition (overall, and radial profile) and size of microparticles without changing chemistry nor increasing temperature. The platforms offers the ability to conveniently generate uniform microparticles, of controllable size with an ease of scale up.

The present invention relates to a ceramic solid electrolyte, which is a key component of an all-solid-state lithium secondary battery, for improving safety, and a method for synthesizing the same. The present invention relates to an oxide-based conductive ceramic of a new NASICON structure of the chemical formula Li.sub.1+xAl.sub.xX.sub.2−xP.sub.3O.sub.12 (X is Zr, Si, Sn, or Y, 0<x<2) or Li.sub.1+xZr.sub.2X.sub.xP.sub.3−xO.sub.12 (X=Si, Sn, Ge, or Y, 1.5≤x≤2.3). The present invention relates to a method for manufacturing an oxide-based conductive ceramic having the above novel NASICON structure.

Provided are a positive active material for a lithium secondary battery, a method of preparing the positive active material, a positive electrode for a lithium secondary battery including the positive active material, and a lithium secondary battery including a positive electrode including the positive active material, in which the positive active material may include a nickel-based lithium metal oxide secondary particle including a plurality of large primary particles, the nickel-based lithium metal oxide secondary particle may have a hollow structure having a pore inside, a size of each of the large primary particles may be in a range of about 2 micrometers (μm) to about 6 μm, and a size of the nickel-based lithium metal oxide secondary particle may be in a range of about 10 μm to about 18 μm.

Methods of synthesis of mesoporous silica are disclosed. The mesoporous silica synthesized herein, like SBA-15, possesses a two-dimensional, hexagonal, through-hole structure with a space group p6mm. An effective quantity of one or more water-soluble oxidized disulfide oil (ODSO) compounds are used during synthesis to impart distinct characteristics.