This invention provides a groundbreaking approach to PLNPs and their preparation. In particular, the synthetic methodology disclosed herein fundamentally differs from the traditional solid-state annealing reactions that require extreme and harsh reaction conditions. In one unique aspect of the invention, a simple, one-step mesoporous template method utilizing mesoporous silica nanoparticles (MSNs) is disclosed that affords in vivo rechargeable NIR-emitting mesoporous PLNPs with uniform size and morphology. In another unique aspect of the invention, the novel synthetic approach is based on aqueous-phase chemical reactions conducted in mild conditions, resulting in uniform and homogeneous PLNPs with desired size control (e.g., sub-10 nm).

This invention provides a groundbreaking approach to PLNPs and their preparation. In particular, the synthetic methodology disclosed herein fundamentally differs from the traditional solid-state annealing reactions that require extreme and harsh reaction conditions. In one unique aspect of the invention, a simple, one-step mesoporous template method utilizing mesoporous silica nanoparticles (MSNs) is disclosed that affords in vivo rechargeable NIR-emitting mesoporous PLNPs with uniform size and morphology. In another unique aspect of the invention, the novel synthetic approach is based on aqueous-phase chemical reactions conducted in mild conditions, resulting in uniform and homogeneous PLNPs with desired size control (e.g., sub-10 nm).

This invention provides a groundbreaking approach to PLNPs and their preparation. In particular, the synthetic methodology disclosed herein fundamentally differs from the traditional solid-state annealing reactions that require extreme and harsh reaction conditions. In one unique aspect of the invention, a simple, one-step mesoporous template method utilizing mesoporous silica nanoparticles (MSNs) is disclosed that affords in vivo rechargeable NIR-emitting mesoporous PLNPs with uniform size and morphology. In another unique aspect of the invention, the novel synthetic approach is based on aqueous-phase chemical reactions conducted in mild conditions, resulting in uniform and homogeneous PLNPs with desired size control (e.g., sub-10 nm).

This invention provides a groundbreaking approach to PLNPs and their preparation. In particular, the synthetic methodology disclosed herein fundamentally differs from the traditional solid-state annealing reactions that require extreme and harsh reaction conditions. In one unique aspect of the invention, a simple, one-step mesoporous template method utilizing mesoporous silica nanoparticles (MSNs) is disclosed that affords in vivo rechargeable NIR-emitting mesoporous PLNPs with uniform size and morphology. In another unique aspect of the invention, the novel synthetic approach is based on aqueous-phase chemical reactions conducted in mild conditions, resulting in uniform and homogeneous PLNPs with desired size control (e.g., sub-10 nm).

Provided is an oxide phosphor having a light emission peak in a wavelength range from red light to near-infrared light. An oxide phosphor having a composition represented by Formula (1): (Li.sub.1?uM.sup.1.sub.u).sub.2M.sup.2.sub.vM.sup.3.sub.wO.sub.x:Cr.sub.y,M.sup.4.sub.z (1). wherein M.sup.1 is at least one element selected from the group consisting of Na, K, Rb and Cs; M.sup.2 is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn; M.sup.3 is at least one element selected from the group consisting of Si, Ge, Ti, Zr, Sn, and Hf; M.sup.4 is at least one element selected from the group consisting of Ni, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb; and u, v, w, x, y, and z satisfy 0?u?1.0, 0.8?v?3.0, 1.8?w?6, 5.4?x?16, 0.005?y?1.0, and 0?z?0.5, respectively.

This invention provides a groundbreaking approach to PLNPs and their preparation. In particular, the synthetic methodology disclosed herein fundamentally differs from the traditional solid-state annealing reactions that require extreme and harsh reaction conditions. In one unique aspect of the invention, a simple, one-step mesoporous template method utilizing mesoporous silica nanoparticles (MSNs) is disclosed that affords in vivo rechargeable NIR-emitting mesoporous PLNPs with uniform size and morphology. In another unique aspect of the invention, the novel synthetic approach is based on aqueous-phase chemical reactions conducted in mild conditions, resulting in uniform and homogeneous PLNPs with desired size control (e.g., sub-10 nm).

A method of forming a metal gallate spinel structure that includes mixing a divalent metal-containing salt and a gallium-containing salt in solution with fermentative or thermophilic bacteria. In the process, the bacteria nucleate metal gallate spinel nano-objects from the divalent metal-containing salt and the gallium-containing salt without requiring reduction of a metal in the solution. The metal gallate spinel structures, as well as light-emitting structures in which they are incorporated, are also described.

An oxide fluorescent material has a composition represented by the following formula (1):

(Mg.sub.1-pM.sup.1.sub.p).sub.q(Li.sub.1-rM.sup.2.sub.r).sub.s(In.sub.1-tM.sup.3.sub.t).sub.u(Ge.sub.1-vM.sup.4.sub.v).sub.wOx:Cr.sub.y,M.sup.5.sub.z(1) wherein M.sup.1 represents at least one element selected from the group consisting of Ca, Sr, Ba, and Zn; M.sup.2 represents at least one element selected from the group consisting of Na, K, Rb, and Cs; M.sup.3 represents at least one element selected from the group consisting of Al, Ga, and Sc; M.sup.4 represents at least one element selected from the group consisting of Si, Ti, Zr, Sn, and Hf; M.sup.5 represents at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb; and p, q, r, s, t, u, v, w, x, y, and z satisfy 0p1.0, 0.1q0.9, 0r1.0, 0.05s0.45, 0t0.5, 0.05u0.45, 0v1.0, 0.8w1.3, 2.6x3.6, 0.002y0.5, 0z0.3, and 0.9q+s+u1.2.

Embodiments provide a light-emitting element that includes: a first electrode, a second electrode disposed on the first electrode, an emission layer disposed between the first electrode and the second electrode and including a quantum dot, a hole transport region disposed between the first electrode and the second electrode, and an electron transport region disposed between the first electrode and the second electrode. The emission layer is disposed between the hole transport region and the electron transport region. At least one of the hole transport region and the electron transport region includes a metal nanoparticle, wherein the metal nanoparticle includes a core including a metal oxide and a ligand bonded the core. The ligand includes an acidic functional group, a basic functional group, or an ultraviolet-reactive functional group.