The present invention is to provide a heteroatom-doped nanodiamond, the heteroatom-doped nanodiamond being doped with at least one heteroatom, the heteroatom-doped nanodiamond satisfying criteria (i) and/or (ii) below: (i) a BET specific surface area being from 20 to 900 m.sup.2/g, and (ii) an average size of primary particles being from 2 to 70 nm.

A boron nitride fluorescent material, having at least one light emission peak wavelength in a range of 480 nm or more and less than 650 nm as excited with light having a light emission peak wavelength in a range of 250 nm or more and 460 nm or less, and comprising: at least one element A selected from the group consisting of alkaline earth metal elements; nitrogen and boron; and optionally at least one element M1 selected from the group consisting of Tb, Sm, Pr, Ce, Mn, and Yb.

A boron nitride fluorescent material, having at least one light emission peak wavelength in a range of 480 nm or more and less than 650 nm as excited with light having a light emission peak wavelength in a range of 250 nm or more and 460 nm or less, and comprising: at least one element A selected from the group consisting of alkaline earth metal elements; nitrogen and boron; and optionally at least one element M1 selected from the group consisting of Tb, Sm, Pr, Ce, Mn, and Yb.

The invention discloses use of a uranium-containing compound as a scintillator. The uranium-containing compound is a uranium-containing organic-inorganic hybrid compound or a uranium-containing inorganic compound. The uranium-containing organic-inorganic hybrid compound is a uranium-containing organic carboxylate or a uranium-containing organophosphate. The uranium-containing inorganic compound is a uranium-containing non-metallate, a uranium-containing metal salt, or a uranium-containing halide. The invention discloses the uranium-containing organic-inorganic compound or the uranium-containing inorganic compound having intrinsic scintillating ability, and provides a new concept and method for the development of (organic-inorganic, inorganic) scintillators of various chemical compositions and configurations with the uranium element.

The invention discloses use of a uranium-containing compound as a scintillator. The uranium-containing compound is a uranium-containing organic-inorganic hybrid compound or a uranium-containing inorganic compound. The uranium-containing organic-inorganic hybrid compound is a uranium-containing organic carboxylate or a uranium-containing organophosphate. The uranium-containing inorganic compound is a uranium-containing non-metallate, a uranium-containing metal salt, or a uranium-containing halide. The invention discloses the uranium-containing organic-inorganic compound or the uranium-containing inorganic compound having intrinsic scintillating ability, and provides a new concept and method for the development of (organic-inorganic, inorganic) scintillators of various chemical compositions and configurations with the uranium element.

An object is to provide a new type of near-infrared ray-emitting phosphor which exhibits excellent emission intensity. A near-infrared ray-emitting phosphor is represented by a general formula, (Y,Lu,Gd).sub.3-x-y (Ga,Al,Sc).sub.5O.sub.12:(Cr.sub.x,(Yb,Nd).sub.y) (0.05<x<0.3, 0≤y<0.3).

A semiconductor quantum dot is provided with a non-metallic substrate, and has a particle size ranged from 0.3 to 100 nm. A method of carrying out a chemical reaction or a photoluminescence reaction by using the semiconductor quantum dot is also provided. A redox reaction of a target sample is carried out, an active substance is generated, or an electron-hole pair is produced from the semiconductor quantum dot by providing the semiconductor quantum dot with a predetermined energy. Photons are released by the combination of the electron-hole pair so as to perform the photoluminescence reaction.

A phosphorescent phosphor having a high afterglow luminance is provided. The phosphorescent phosphor comprises, as a matrix, a compound represented by MAl.sub.2O.sub.4, the metal element represented by M comprising Sr, Mg and Ba, and the phosphorescent phosphor containing, Eu as an activator, and Dy as a co-activator, wherein the content of Eu, in terms of molar ratio, is 0.001Eu/(M+Eu+Dy)0.05; the content of Dy, in terms of molar ratio, is 0.004Dy/(M+Eu+Dy)0.06; the content of Mg, in terms of molar ratio, is 0.02Mg/(M+Eu+Dy)0.1; the content of Ba, in terms of molar ratio, is 0.03Ba/(M+Eu+Dy)0.15; and the phosphorescent phosphor contains at least one alkali metal element of the group consisting of Li, Na, K and rubidium (Rb). Mg and Ba as well as the alkali metal element(s) contained in the phosphorescent phosphor provide an excellent phosphorescent phosphor having a high afterglow luminance.

A semiconductor quantum dot is provided with a non-metallic substrate, and has a particle size ranged from 0.3 to 100 nm. A method of carrying out a chemical reaction or a photoluminescence reaction by using the semiconductor quantum dot is also provided. A redox reaction of a target sample is carried out, an active substance is generated, or an electron-hole pair is produced from the semiconductor quantum dot by providing the semiconductor quantum dot with a predetermined energy. Photons are released by the combination of the electron-hole pair so as to perform the photoluminescence reaction.

A boron nitride fluorescent material, having at least one light emission peak wavelength in a range of 480 nm or more and less than 650 nm as excited with light having a light emission peak wavelength in a range of 250 nm or more and 460 nm or less, and comprising: at least one element A selected from the group consisting of alkaline earth metal elements; nitrogen and boron; and optionally at least one element M1 selected from the group consisting of Tb, Sm, Pr, Ce, Mn, and Yb.