A composite nanomaterial of ZnO impregnated by, e.g., a green copper phthalocyanine compound (CuPc) can be an efficient solar light photocatalyst for water remediation. The composite may include hollow shell microspheres and hollow nanospheres of CuPc-ZnO. CuPc may function as a templating and/or structure modifying agent, e.g., for forming hollow microspheres and/or nanospheres of ZnO particles. The composite can photocatalyze the degradation of organic pollutants such as crystal violet (CV) and 2,4-dichlorophenoxyacetic acid as well as microbes in water under solar light irradiation. The ZnO—CuPc composite can be stable and recyclable under solar irradiation.

The present relates to a method for producing calcium sulfate solid crystals and hydrochloric acid (HCl) from a calcium chloride solution comprising the steps of feeding a continuous stirred-tank reactor with a calcium chloride solution, sulfuric acid and water; mixing the calcium chloride solution, sulfuric acid and water in the reactor; and maintaining the reactor a temperature of less than about 70° C., converting the calcium chloride solution, sulfuric acid and water into HCl and calcium sulfate solid crystals. The method described herein can be incorporated as a means for regenerating HCl from CaCl.sub.2 solutions which are generated in the metallurgical industry when processing calcium-bearing ores for recovering metals like rare earth elements.

The invention provides chunk polycrystalline silicon having a concentration of carbon at the surface of 0.5-35 ppbw. A process for cleaning polycrystalline silicon chunks having carbon contaminations at the surface, includes a thermal treatment of the polycrystalline silicon chunks in a reactor at a temperature of 350 to 600° C., the polycrystalline silicon chunks being present in an inert gas atmosphere during the thermal treatment, and the polycrystalline silicon chunks after the thermal treatment having a concentration of carbon at the surface of 0.5-35 ppbw.

Na-rich electrolyte compositions provided herein can be used in a variety of devices, such as sodium ionic batteries, capacitors and other electrochemical devices. Na-rich electrolyte compositions provided herein can have a chemical formula of Na.sub.3OX, Na.sub.3SX, Na .sub.(3-δ) M.sub.δ/2OX and Na .sub.(3-δ) M.sub.δ/2SX wherein 0<δ<0.8, wherein X is a monovalent anion selected from fluoride, chloride, bromide, iodide, H.sup.−, CN.sup.−, BF.sub.4.sup.−, BH.sub.4.sup.−, ClO.sub.4.sup.−, CH.sub.3.sup.−, NO.sub.2.sup.−, NH.sub.2.sup.− and mixtures thereof, and wherein M is a divalent metal selected from the group consisting of magnesium, calcium, barium, strontium and mixtures thereof. Na-rich electrolyte compositions provided herein can have a chemical formula of Na .sub.(3-δ) M.sub.δ/3OX and/or Na .sub.(3-δ) M.sub.δ/3SX; wherein 0<δ<0.5, wherein M is a trivalent cation M.sup.3, and wherein X is selected from fluoride, chloride, bromide, iodide, H.sup.−, CN.sup.−, BF.sub.4.sup.−, BH.sub.4.sup.−, ClO.sub.4.sup.−, CH.sub.3.sup.−, NO.sub.2.sup.−, NH.sup.2− and mixtures thereof. Synthesis and processing methods of NaRAP compositions for battery, capacitor, and other electrochemical applications are also provided.

The invention relates to polyoxometalates represented by the formula (A.sub.n).sup.m+[M′M.sub.12X.sub.8O.sub.yR.sub.zH.sub.q].sup.m− or solvates thereof, corresponding supported polyoxometalates, and processes for their preparation, as well as corresponding metal clusters, optionally in the form of a dispersion in a liquid carrier medium or immobilized on a solid support, and processes for their preparation, as well as their use in reductive conversion of organic substrate.

Surface-modified layered double hydroxides (LDHs) are disclosed, as well as processes by which they are made, and uses of the LDHs in composite materials. The surface-modified LDHs of the invention are more organophilic than their unmodified analogues, which allows the LDHs to be incorporated in a wide variety of materials, wherein the interesting functionality of LDHs may be exploited.

VO.sub.2 and V.sub.2O.sub.5 nano- or micro-materials. The VO.sub.2 nano-materials and micro-materials have an M1 phase structure and oxygen stoichiometry that deviates 2% or less from theoretical stoichiometry. The VO.sub.2 nano-materials and micro-materials may doped with cation dopants and/or anion dopants. The VO.sub.2 and V.sub.2O.sub.5 nano- or micro-materials can be made by hydrothermal methods starting with V.sub.3O.sub.7.H.sub.2O nano- or micro-material. The VO.sub.2 and V.sub.2O.sub.5 nano- or micro-materials can be used as, for example, thermochromic window coatings.

There are provided a graphene having an oxygen atom content in a predetermined range or less and a carbon/oxygen weight ratio in a specific range to show excellent electrical and thermal conductivity properties, and a barrier property, and a method and an apparatus for preparing the graphene having excellent electrical and thermal conductivity properties and a barrier property by using a subcritical-state fluid or a supercritical-state fluid. According to the method and the apparatus for preparing the graphene, impurities such as graphene oxide, and the like, may be effectively removed, such that uniformity of the graphene to be prepared may be increased, and therefore, the graphene which is highly applicable as materials throughout the industry may be mass-produced.

A manufacturing method of ceramic powder includes mixing a barium carbonate having a specific surface are of 15 m.sup.2/g or more, a titanium dioxide having a specific surface area of 20 m.sup.2/g or more, a first compound of a donor element having a larger valence than Ti, and a second compound of an acceptor element having a smaller valence than Ti and having a larger ion radium than Ti and the donor element, and synthesizing barium titanate powder by calcining the barium carbonate, the titanium dioxide, the first compound and the second compound until a specific surface area of the barium titanate powder becomes 4 m.sup.2/g or more and 25 m.sup.2/g or less.

A method for producing nano-clays comprising forming a mixture of a clay and water, wherein water is present in an amount of from 2 to 10% by weight of the total weight of clay and water, and milling the mixture of clay and water in the presence of a grinding media to form the nano-clay.