A nitride semiconductor material having low lattice thermal conductivity and a heat flow switching element including the same are provided. The nitride semiconductor material according to the present invention is a metal nitride represented by M-SiNTe (where M represents at least one kind of transition metal element, and Te represents an arbitrary element), and has a thermal effusivity of less than 2000 Ws.sup.0.5/m.sup.2K. In particular, the M is at least one of Cr, Mn, Ni, Mo, and W. In addition, a heat flow switching element according to the present invention includes an N-type semiconductor layer 3, an insulator layer 4 formed on the N-type semiconductor layer, and a P-type semiconductor layer 5 formed on the insulator layer, wherein at least one of the N-type semiconductor layer and the P-type semiconductor layer is formed from the nitride semiconductor material described above.

Provided a method for producing a nitride phosphor. The method includes preparing a mixture that comprises a first nitride and a cerium source, the first nitride comprising, as a host crystal, a crystal having the same crystal structure as CaAlSiN.sub.3; and performing a heat treatment of the mixture at a temperature of 1,300? C. to 1,900? C. to obtain a second nitride. The first nitride comprises aluminum, silicon, nitrogen, and at least one selected from the group consisting of lithium, calcium, and strontium.

The present invention provides a zinc nitride compound suitable for electronic devices such as high-speed transistors, high-efficiency visible light-emitting devices, high-efficiency solar cells, and high-sensitivity visible light sensors. The zinc nitride compound is represented, for example, by the chemical formula CaZn.sub.2N.sub.2 or the chemical formula X.sup.1.sub.2ZnN.sub.2 wherein X.sup.1 is Be or Mg. The zinc nitride compound is preferably synthesized at a high pressure of 1 GPa or more.

The present disclosure is directed to antennas for transmitting and/or receiving electrical signals comprising a MXene composition, devices comprising these antennas, and methods of transmitting and receiving signals using these antennas.

Reactant materials for use in the synthesis of compounds comprising a non-metal and hydrogen, and methods of making and using the same are provided. The reactant materials generally comprise first and second non-metals, metals, a cation, and a transition metal, and can be formed and used in reactions occurring at relatively low-pressure conditions using heat energy that can be supplied via solar radiation. In particular, the reactant materials can be used in the synthesis of ammonia and various hydrocarbon compounds using air, water, and sunlight.

The present invention provides a zinc nitride compound suitable for electronic devices such as high-speed transistors, high-efficiency visible light-emitting devices, high-efficiency solar cells, and high-sensitivity visible light sensors. The zinc nitride compound is represented, for example, by the chemical formula CaZn.sub.2N.sub.2 or the chemical formula X.sup.1.sub.2ZnN.sub.2 wherein X.sup.1 is Be or Mg. The zinc nitride compound is preferably synthesized at a high pressure of 1 GPa or more.

An object is to provide a piezoelectric body having a value indicating a higher performance index (d.sub.33, e.sub.33, C.sub.33, g.sub.33, and/or k.sup.2) than aluminum nitride not doped with any element. The piezoelectric body is represented by a chemical formula Al.sub.1-X-YMg.sub.XM.sub.YN where X+Y is less than 1, X is in a range of more than 0 and less than 1, and Y is in a range of more than 0 and less than 1.

Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

Methods and materials are disclosed for simultaneously optimizing both the piezoelectric and mechanical properties of wurtzite piezoelectric materials based on the AlN wurtzite and alloyed with one or two end-members from the set BN, YN, CrN, and ScN.

The present invention discloses a nitrogen-containing luminescent particle, characterized in that a structure of the nitrogen-containing luminescent particle is divided into an oxygen poor zone, a transition zone, and an oxygen rich zone from a core to an outer surface of the particle depending on an increasing oxygen content, the oxygen poor zone being predominantly a nitride luminescent crystal or oxygen-containing solid solution thereof, the transition zone being predominantly a nitroxide material, the oxygen rich zone being predominantly an oxide material or oxynitride material; the nitride luminescent crystal or oxygen-containing solid solution thereof has a chemical formula of M.sub.m-m1A.sub.a1B.sub.b1O.sub.o1N.sub.n1:R.sub.m1, the nitroxide material has a chemical formula of M.sub.m-m2A.sub.a2B.sub.b2O.sub.o2N.sub.n2:R.sub.m2, the oxide material or oxynitride material has a chemical formula of M.sub.m-m3A.sub.a3B.sub.b3O.sub.o3N.sub.n3:R.sub.m3. The nitrogen-containing luminescent particle and the nitrogen-containing illuminant of the present invention have good chemical stability, good aging and light decay resistance, and high luminescent efficiency, and are useful for various luminescent devices. The manufacturing method of the present invention is easy and reliable, and useful for industrial mass production.