Methods for modifying the surface termination of two-dimensional (2D) transition metal carbides (MXenes) are provided. The methods, which allow for versatile chemical modification of the terminating anions via halide exchange or substitution and elimination reactions in molten inorganic salts, provide a processing approach that is widely applicable to MXenes as a broad class of functional materials.

Methods for modifying the surface termination of two-dimensional (2D) transition metal carbides (MXenes) are provided. The methods, which allow for versatile chemical modification of the terminating anions via halide exchange or substitution and elimination reactions in molten inorganic salts, provide a processing approach that is widely applicable to MXenes as a broad class of functional materials.

The present disclosure is directed to electroacoustical devices comprising patterned MXene compositions on biaxially oriented polymer substrates and methods of making and using the same.

The present disclosure provides a rigid self-supporting MXene separation membrane and a preparation method and use thereof, belonging to the technical field of membranes. In the present disclosure, a MXene material is mixed with an aluminum salt powder to conduct one-step membrane formation by hot-pressing. The pressure forms the powder into a membrane and imparts rigidity, enabling a self-supporting structure; the heating breaks an ionic bond of an inorganic metal salt to reach a molten ionic state, and free metal cations react with active oxygen-containing functional groups on the surface of the MXene to form new chemical bonds (such as an Al—O bond); such a chemical bond has higher energy, achieving a desirable anti-swelling effect to improve the membrane stability. The separation membrane further has excellent conductivity and hydrophilicity.

The present disclosure provides a rigid self-supporting MXene separation membrane and a preparation method and use thereof, belonging to the technical field of membranes. In the present disclosure, a MXene material is mixed with an aluminum salt powder to conduct one-step membrane formation by hot-pressing. The pressure forms the powder into a membrane and imparts rigidity, enabling a self-supporting structure; the heating breaks an ionic bond of an inorganic metal salt to reach a molten ionic state, and free metal cations react with active oxygen-containing functional groups on the surface of the MXene to form new chemical bonds (such as an Al—O bond); such a chemical bond has higher energy, achieving a desirable anti-swelling effect to improve the membrane stability. The separation membrane further has excellent conductivity and hydrophilicity.

The present invention is directed to methods of transferring urea from an aqueous solution comprising urea to a MXene composition, the method comprising contacting the aqueous solution comprising urea with the MXene composition for a time sufficient to form an intercalated MXene composition comprising urea.

Disclosed herein is a surface treating method using a Taylor reactor wherein a washing, neutralization, heavy metal removal, etc. can be efficiently carried out, while saving a surface treating time and a treatment liquid and enhancing a treatment efficiency by using a Taylor eddy current which in general is formed at a Taylor reactor. The surface treatment method using a Taylor reactor formed of a cylindrical reaction chamber and a cylindrical rotation body which is configured to rotate in the reaction chamber may include (1) a supply step wherein a surface treatment thing and a surface treatment liquid are supplied into the reaction chamber; and (2) a treatment step wherein the surface treatment thing is stayed in the reaction chamber while rotating the cylindrical rotation body, and the stay time of the surface treatment thing is in a range of 1 minute to 6 hours.

Disclosed herein is a surface treating method using a Taylor reactor wherein a washing, neutralization, heavy metal removal, etc. can be efficiently carried out, while saving a surface treating time and a treatment liquid and enhancing a treatment efficiency by using a Taylor eddy current which in general is formed at a Taylor reactor. The surface treatment method using a Taylor reactor formed of a cylindrical reaction chamber and a cylindrical rotation body which is configured to rotate in the reaction chamber may include (1) a supply step wherein a surface treatment thing and a surface treatment liquid are supplied into the reaction chamber; and (2) a treatment step wherein the surface treatment thing is stayed in the reaction chamber while rotating the cylindrical rotation body, and the stay time of the surface treatment thing is in a range of 1 minute to 6 hours.

A composite comprising a MXene and a post-transition metal wherein the post-transition metal is at least partially encapsulated by from 1 to 4 layers of the MXene. Methods of making such a composite are also disclosed.

A composite comprising a MXene and a post-transition metal wherein the post-transition metal is at least partially encapsulated by from 1 to 4 layers of the MXene. Methods of making such a composite are also disclosed.