A method is provided for producing an article which is transparent to IR wavelength in the region of 4 μm to 9 μm. The method includes the steps of (a) Producing ultra-fine powders of ZnS, (b) followed by pretreatment of the ultra-fine powders under reduced gas conditions including H2, H2S, N2, Ar and mixtures there of (c) followed by vacuum (3×10.sup.−6 torr) treatment to remove oxygen and sulfates adsorbed to the surface disposing a plurality of nano-particles on a substrate, wherein said nanoparticles comprise ZnS with ultra-high purity of cubic phase; (b) subjecting the nano-particles to spark plasma sintering thereby producing a sintered ZnS product with IR transmission reaching 75% in the wavelength range of 4 μm to 9 μm.

The present invention provides a semiconductor crystal comprising a semiconductor material having a tuned band gap energy, and methods for preparation thereof. More particularly, the invention provides a semiconductor crystal comprising a semiconductor material and amino acid molecules, peptides, or a combination thereof, incorporated within the crystal lattice, wherein the amino acid molecules, peptides, or combination thereof tune the band gap energy of the semiconductor material.

The present invention provides a semiconductor crystal comprising a semiconductor material having a tuned band gap energy, and methods for preparation thereof. More particularly, the invention provides a semiconductor crystal comprising a semiconductor material and amino acid molecules, peptides, or a combination thereof, incorporated within the crystal lattice, wherein the amino acid molecules, peptides, or combination thereof tune the band gap energy of the semiconductor material.

The invention is directed to a method for producing non-oxide semiconductor nanoparticles, the method comprising: (a) subjecting a combination of reaction components to conditions conducive to microbially-mediated formation of non-oxide semiconductor nanoparticles, wherein said combination of reaction components comprises i) anaerobic microbes, ii) a culture medium suitable for sustaining said anaerobic microbes, iii) a metal component comprising at least one type of metal ion, iv) a non-metal component comprising at least one non-metal selected from the group consisting of S, Se, Te, and As, and v) one or more electron donors that provide donatable electrons to said anaerobic microbes during consumption of the electron donor by said anaerobic microbes; and (b) isolating said non-oxide semiconductor nanoparticles, which contain at least one of said metal ions and at least one of said non-metals. The invention is also directed to non-oxide semiconductor nanoparticle compositions produced as above and having distinctive properties.

The invention is directed to a method for producing non-oxide semiconductor nanoparticles, the method comprising: (a) subjecting a combination of reaction components to conditions conducive to microbially-mediated formation of non-oxide semiconductor nanoparticles, wherein said combination of reaction components comprises i) anaerobic microbes, ii) a culture medium suitable for sustaining said anaerobic microbes, iii) a metal component comprising at least one type of metal ion, iv) a non-metal component comprising at least one non-metal selected from the group consisting of S, Se, Te, and As, and v) one or more electron donors that provide donatable electrons to said anaerobic microbes during consumption of the electron donor by said anaerobic microbes; and (b) isolating said non-oxide semiconductor nanoparticles, which contain at least one of said metal ions and at least one of said non-metals. The invention is also directed to non-oxide semiconductor nanoparticle compositions produced as above and having distinctive properties.

A methodology for synthesizing a nanoparticle batch, such as but not limited to a metal chalcogenide nanoparticle batch and further such as but not limited to a metal sulfide nanoparticle batch is predicated upon an expectation and observation that at elevated concentrations of at least one reactant material within a heat-up nanoparticle batch synthesis method, the resulting nucleated batch comprises nanoparticles that may be dimensionally focused to provide a substantially monodisperse nanoparticle batch. The embodied methodology is also applicable to a continuous reactor. The embodied methodology also considers viscosity as a dimensionally focusing result effective variable.

A methodology for synthesizing a nanoparticle batch, such as but not limited to a metal chalcogenide nanoparticle batch and further such as but not limited to a metal sulfide nanoparticle batch is predicated upon an expectation and observation that at elevated concentrations of at least one reactant material within a heat-up nanoparticle batch synthesis method, the resulting nucleated batch comprises nanoparticles that may be dimensionally focused to provide a substantially monodisperse nanoparticle batch. The embodied methodology is also applicable to a continuous reactor. The embodied methodology also considers viscosity as a dimensionally focusing result effective variable.

A process for preparing alloy products is described using a self-sustaining or self-propagating SHS-type combustion process with point-source ignition, preferably a laser, in a pressurized vessel. Binary, ternary and quaternary alloys can be formed with control over polycrystalline structure and bandgap. Methods to tune the bandgap and the alloys formed are described. The alloy products may be doped. Preferably sulfides, tellurides or selenides are formed. Cooling during reaction takes place.

A process for preparing alloy products is described using a self-sustaining or self-propagating SHS-type combustion process with point-source ignition, preferably a laser, in a pressurized vessel. Binary, ternary and quaternary alloys can be formed with control over polycrystalline structure and bandgap. Methods to tune the bandgap and the alloys formed are described. The alloy products may be doped. Preferably sulfides, tellurides or selenides are formed. Cooling during reaction takes place.

A method is provided for producing an article which is transparent to near-wave IR, mid-wave and Long-wave multi-spectral and IR wavelength in the region of 0.4 pm to 16 μm. The method includes the steps of (a) Producing ultra-fine powder of CaLa.sub.2S.sub.4 via SPLTS process, (b) followed by pretreatment of the ultra-fine powder under inert and reducing gas conditions including H.sub.2 or Argon or N.sub.2 or H.sub.2/H.sub.2S, H.sub.2S, and mixtures there of (c) followed by sieving the powder in 140 mesh screen and cold pressing the powder at 7000 psi for 7 min. into a disk shaped green body (d) then Cold-Isostatic Pressing (CIP) at 40,000 psi for 5 min in a rubber mold (e) finally sintered article of CaLa.sub.2S.sub.4 disk of 25.4 mm diameter with ultra-high density containing cubic phase of CaLa.sub.2S.sub.4 to yield IR transmission of a peak value of 57% within the IR wavelength range of 2 μm to 16 μm, either by using microwave sintering followed by hot isostatic press or spark plasma sintering followed by hot isostatic press or vacuum sintering at (3×10.sup.−6 torr) followed by hot isostatic press or hot press sintering followed by hot isostatic press and finally followed by mirror polished IR article, is obtained.