A one-step salt-assisted general synthetic methodology for the controlled phase transformation of various types of 2H-phase transition metal dichalcogenides (2H-TMDs), yielding large-scale metastable 1T′-phase transition metal dichalcogenides (1T′-TMDs), including WS.sub.2, WSe.sub.2, MoS.sub.2, and MoSe.sub.2 is described. By tuning the reaction conditions, alloyed 1T′-TMDs such as WS.sub.2xSe.sub.2(1−x) and MoS.sub.2xSe.sub.2(1−x) are also obtained. Commercially-available metal salts such as K.sub.2C.sub.2O.sub.4.Math.H.sub.2O, Na.sub.2C.sub.2O.sub.4, K.sub.2CO.sub.3, Na.sub.2CO.sub.3, Cs.sub.2CO.sub.3, Rb.sub.2CO.sub.3, KHCO.sub.3, and NaHCO.sub.3, are demonstrated to be effective for the controlled phase transformation at elevated temperatures in a reducing atmosphere. The technique may be extended to the phase engineering of other materials with various polymorphs.

A one-step salt-assisted general synthetic methodology for the controlled phase transformation of various types of 2H-phase transition metal dichalcogenides (2H-TMDs), yielding large-scale metastable 1T′-phase transition metal dichalcogenides (1T′-TMDs), including WS.sub.2, WSe.sub.2, MoS.sub.2, and MoSe.sub.2 is described. By tuning the reaction conditions, alloyed 1T′-TMDs such as WS.sub.2xSe.sub.2(1−x) and MoS.sub.2xSe.sub.2(1−x) are also obtained. Commercially-available metal salts such as K.sub.2C.sub.2O.sub.4.Math.H.sub.2O, Na.sub.2C.sub.2O.sub.4, K.sub.2CO.sub.3, Na.sub.2CO.sub.3, Cs.sub.2CO.sub.3, Rb.sub.2CO.sub.3, KHCO.sub.3, and NaHCO.sub.3, are demonstrated to be effective for the controlled phase transformation at elevated temperatures in a reducing atmosphere. The technique may be extended to the phase engineering of other materials with various polymorphs.

An exemplary method for producing a mixed metal chalcogenide under atmospheric pressure may include forming a reaction mixture by mixing a first metal chalcogenide and a second metal chalcogenide. An exemplary method may further include pouring a first layer of NaCl within a reactor, where an exemplary reactor may include a container and a cap. Pouring an exemplary first layer of NaCl within an exemplary reactor may include pouring an exemplary first layer of NaCl on an exemplary base end of an exemplary container of the exemplary reactor. An exemplary method may further include pouring an exemplary reaction mixture into an exemplary container on top of an exemplary first layer of NaCl, pouring a second layer of NaCl into an exemplary container on top of an exemplary reaction mixture, sealing an exemplary container by closing an exemplary cap and pouring molten NaCl on top of the exemplary cap, and heating an exemplary reactor at a predetermined temperature for a predetermined time.

A method of producing an inorganic material (S10) according to the present invention includes a vitrification step (S12) of applying shearing stress and compressive stress to a mixed powder (MP) of a plurality of kinds of inorganic compound powders by using a ring ball mill mechanism (70) to vitrify at least a part of the mixed powder (MP); and a dispersion step (S13) of dispersing the vitrified mixed powder (MP) after the vitrification step (S12), where a combined step of the vitrification step (S12) and the dispersion step (S13) is performed a plurality of times to obtain a vitrified inorganic material powder from the mixed powder.

A process for preparing stacks of metal chalcogenide flakes includes: (a) reacting together a source of the metal atom of the target metal chalcogenide with a source of the chalcogenide atom of the target metal chalcogenide, in the presence of a spacer, so as to produce flakes of the metal chalcogenide; (b) depositing metal chalcogenide flakes obtained using step (a) onto a substrate to form a stack of assembled metal chalcogenide flakes, wherein the spacer contains an alkyl chain linked to a functional group able to bond to the metal chalcogenide surface, said alkyl chain having a length of less than 18 carbon atoms, preferably between 6 and 14 carbon atoms.

A method of improving leach kinetics and recovery during atmospheric or above-atmospheric leaching of a metal sulfide is disclosed. A system for practicing the aforementioned method is also disclosed. Apparatus for practicing the aforementioned method is also disclosed. A new composition of matter which is formed by the aforementioned method, and which may be utilized in the system and apparatus is further disclosed. The new composition of matter may exhibit improved leach kinetics, and may have some utility in the semi-conductor arts, including uses within photovoltaic materials.

A method of improving leach kinetics and recovery during atmospheric or above-atmospheric leaching of a metal sulfide is disclosed. A system for practicing the aforementioned method is also disclosed. Apparatus for practicing the aforementioned method is also disclosed. A new composition of matter which is formed by the aforementioned method, and which may be utilized in the system and apparatus is further disclosed. The new composition of matter may exhibit improved leach kinetics, and may have some utility in the semi-conductor arts, including uses within photovoltaic materials.

The present invention is directed to methods of preparing metal sulfide, metal selenide, or metal sulfide/selenide nanoparticles and the products derived therefrom. In various embodiments, the nanoparticles are derived from the reaction between precursor metal salts and certain sulfur- and/or selenium-containing precursors each independently having a structure of Formula (I), (II), or (III), or an isomer, salt, or tautomer thereof, where Q.sup.1,Q.sup.2,Q.sup.3,R.sup.1,R.sup.2,R.sup.3,R.sup.5, and X are defined within the specification.

Provided are nanoparticles passivated with a cationic metal-chalcogenide complex (MCC) and a method of preparing the same. A passivated nanoparticle includes: a core nanoparticle; and a cationic metal-chalcogenide compound (MCC) fixed on a surface of the core nanoparticle.

Provided are nanoparticles passivated with a cationic metal-chalcogenide complex (MCC) and a method of preparing the same. A passivated nanoparticle includes: a core nanoparticle; and a cationic metal-chalcogenide compound (MCC) fixed on a surface of the core nanoparticle.