The present technology is directed to the nanoparticles for use as molecular environmental sensors. The nanoparticles comprise a photoluminescence core and a plurality of ligands bound to the core and forming a quencher permeable ligand shell. The ligands comprise a reactive or charged moiety capable of being modulated between a first stand and a second state, and the proportion of ligands in each state determine the permeability of the ligand shell to a photoluminescence quencher.

The present invention provides the use of a lead (IV) containing compound to prepare a lead chalcogenide nanocrystal and a method for producing broadband lead chalcogenide nanocrystals in a low cost, size-controllable and scalable method, the method comprising contacting a lead (IV) containing compound with an organic acid and a chalcogen-containing reagent.

The present invention provides the use of a lead (IV) containing compound to prepare a lead chalcogenide nanocrystal and a method for producing broadband lead chalcogenide nanocrystals in a low cost, size-controllable and scalable method, the method comprising contacting a lead (IV) containing compound with an organic acid and a chalcogen-containing reagent.

A nanocrystal with a large Stokes shift includes a matrix domain having a composition of M1.sub.xM2.sub.yA.sub.z, and a plurality of seed domains which are distributed in the matrix domain and each of which has a composition of M1.sub.x′M2.sub.y′A.sub.z′, wherein M1, M2, A, x, y, z, x′, y′, and z′ are as defined herein.

A nanocrystal with a large Stokes shift includes a matrix domain having a composition of M1.sub.xM2.sub.yA.sub.z, and a plurality of seed domains which are distributed in the matrix domain and each of which has a composition of M1.sub.x′M2.sub.y′A.sub.z′, wherein M1, M2, A, x, y, z, x′, y′, and z′ are as defined herein.

A photodetector element contains aggregates of PbS quantum dots and a ligand that is coordinated to the PbS quantum dot, in which the PbS quantum dot contains 1.75 mol or more and 1.95 mol or less of a Pb atom with respect to 1 mol of a S atom.

A photodetector element contains aggregates of PbS quantum dots and a ligand that is coordinated to the PbS quantum dot, in which the PbS quantum dot contains 1.75 mol or more and 1.95 mol or less of a Pb atom with respect to 1 mol of a S atom.

A nanomaterial includes quantum dots having a crystal structure, wherein the quantum dots include an exposed surface in a specific direction, and the exposed surface has a ligand bound thereto.

A nanomaterial includes quantum dots having a crystal structure, wherein the quantum dots include an exposed surface in a specific direction, and the exposed surface has a ligand bound thereto.

A semiconductor film contains aggregates of semiconductor quantum dots containing a metal atom and a ligand that is coordinated to the semiconductor quantum dot, where the ligand contains a first ligand that is an inorganic halide and a second ligand that is represented by any one of Formulae (A) to (C). X.sup.A1 and X.sup.A2 are separated by L.sup.A1 by 1 or 2 atoms, X.sup.B1 and X.sup.B3, and X.sup.B2 and X.sup.B3 are respectively independently separated by L.sup.B1 and L.sup.B2 by 1 or 2 atoms, and X.sup.C1 and X.sup.C4, X.sup.C2 and X.sup.C4, and X.sup.C3 and X.sup.C4 are respectively independently separated by L.sup.C1, L.sup.C2, or L.sup.C3 by 1 or 2 atoms.

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