Method of microbially producing metal gallate spinel nano-objects, and compositions produced thereby

1. A method of forming a metal gallate spinel structure, the method comprising:

providing a supply of fermentative or thermophilic bacteria;

reacting a divalent metal-containing salt and a gallium-containing salt with the supply of fermentative or thermophilic bacteria, wherein treatment of the divalent metal-containing salt and the gallium-containing salt with the fermentative or thermophilic bacteria nucleates a divalent metal gallate spinel structure.

2. The method of claim 1 , further comprising including at least one dopant in the presence of said divalent metal-containing salt, gallium-containing salt and fermentative or thermophilic bacteria to nucleate a divalent metal gallate spinel structure containing said at least one dopant.

3. The method of claim 1 , wherein the fermentative or thermophilic bacteria comprises Thermoanaerobacter bacteria.

4. The method of claim 1 , wherein the divalent metal-containing salt, the gallium-containing salt and the supply of fermentative or thermophilic bacteria are contained in an aqueous solution.

5. The method of claim 1 , wherein a zinc gallate spinel structure is formed by selecting the divalent metal-containing salt as a zinc-containing salt, wherein treatment of the zinc-containing salt and the gallium-containing salt with the fermentative or thermophilic bacteria nucleates a zinc gallate spinel structure.

6. The method of claim 5 , further comprising including at least one dopant in the presence of said zinc-containing salt, gallium-containing salt and fermentative or thermophilic bacteria to nucleate a zinc gallate spinel structure containing said at least one dopant.

7. The method of claim 5 , wherein the zinc-containing salt is selected from zinc chloride (ZnCl 2 ), zinc bromide (ZnBr 2 ), zinc nitrate hydrate (Zn(NO 3 ) 2 .xH 2 O), zinc sulfate hydrate (ZnSO 4 .xH 2 O), zinc phosphate (Zn 3 (PO 4 ) 2 ), zinc acetate hydrate ((CH 3 CO 2 ) 2 Zn).xH 2 O), zinc stearate ([CH 3 (CH 2 ) 16 COO] 2 Zn), zinc fluoride (ZnF 2 ), zinc iodide (ZnI 2 ), zinc methoxide (C 2 H 6 O 2 Zn), zinc acrylate ((H 2 C═CHCO 2 ) 2 Zn), and combinations thereof.

8. The method of claim 1 , wherein the gallium-containing salt is selected from gallium chloride (GaCl 3 ), gallium chloride (GaCl 2 ), gallium nitrate hydroxide (GaNO 3 .xH 2 O), gallium fluoride (GaF 3 ), gallium iodide (GaI 3 ), gallium bromide (GaBr 3 ), gallium sulfate hydrate (GaSO 4 .xH 2 O), and combinations thereof.

9. The method of claim 5 , wherein the zinc gallate spinel structure is ZnGa 2 O 4 .

10. The method of claim 1 , wherein the treatment of the divalent metal-containing salt and the gallium-containing salt with the fermentative or thermophilic bacteria to nucleate the divalent metal gallate spinel structure comprises adjusting a pH of a solution of the divalent metal-containing salt, the gallium-containing salt, and the fermentative or thermophilic bacteria within a range of 5.5 to 8.5.

11. The method of claim 1 , wherein the treatment of the divalent metal-containing salt and the gallium-containing salt with the fermentative or thermophilic bacteria to nucleate the divalent metal gallate spinel structure comprises adjusting an E h of a solution of the divalent metal-containing salt, the gallium-containing salt, and the thermophilic bacteria within a range of 100 mV to -350 mV.

12. The method of claim 5 , wherein the zinc gallate spinel structure is a blue phosphor.

13. The method of claim 2 , wherein the dopant is at least one selected from the group consisting of Mn, Cr, Eu, Co, Dy, and combinations thereof.

14. The method of claim 6 , wherein the doping of the zinc gallate spinel comprises Co 2+ dopant and the wavelength of light emission ranges from 400 nm to 495 nm.

15. The method of claim 6 , wherein the zinc gallate spinel is doped with Mn 2 + dopant and the wavelength of light emission ranges from 495 nm to 570 nm.

16. The method of claim 15 , wherein doping of the zinc gallate spinel structure with Mn 2+ comprises mixing a manganese salt selected from manganese chloride hydrate(MnCl 2 .xH 2 O), manganese nitrate hydrate (Mn(NO 3 ) 2 .xH 2 O), manganese sulfate hydrate (MnSO 4 .xH 2 O), manganese iodide (MnI 2 ), manganese bromide (MnBr 2 ), manganese fluoride (MnF 3 ), manganese acetate hydrate (Mn(CH 3 COO) 2 .xH 2 O), and manganese carbonate (MnCO 3 ) with said divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in said method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Mn 2+ .

17. The method of claim 6 , wherein the zinc gallate spinel is doped with Cr 3+ or Eu 3+ and the wavelength of light emission ranges from 570 nm to 750 nm.

18. The method of claim 17 , wherein doping of the zinc gallate spinel structure with Cr 3+ comprises mixing a chromium salt selected from chromium chloride hydrate (CrCl 3 .xH 2 O), chromium nitrate hydrate (Cr(NO 3 ) 3 .xH 2 O), chromium acetate hydroxide ((CH 3 CO 2 ) 7 Cr 3 (OH) 2 ), chromium sulfate hydrate (Cr 2 (SO 4 ) 3 .xH 2 O), chromium fluoride hydrate (GaF 3 .xH 2 O), chromium iodide hydrate (CrI 3 .xH 2 O), chromium bromide hydrate (CrBr 3 .xH 2 O), and chromium phosphate hydrate (Cr(PO 4 ).xH 2 O), with said divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in said method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Cr 3+ .

19. The method of claim 17 , wherein doping of the zinc gallate spinel structure with Eu 3+ comprises mixing a europium salt selected from europium chloride hydrate (EuCl 3 .xH 2 O), europium fluoride hydrate (EuF 3 .xH 2 O), europium nitrate hydrate (Eu(NO 3 ) 3 .xH 2 O), europium acetate hydroxide ((CH 3 CO 2 ) 7 Eu 3 (OH) 2 ), europium bromide hydrate (EuBr 3 .xH 2 O), and europium sulfate hydrate (Eu 2 (SO 4 ) 3 .xH 2 O with said divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in said method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Eu 3+ .

20. The method of claim 6 , wherein the zinc gallate spinel is doped with Dy 3+ dopant and the wavelength of light emission is in a wavelength ranging from 450 nm to 510 nm, or a wavelength ranging from 560 nm to 610 nm, or a wavelength ranging from 660 nm to 720 nm, or a wavelength ranging from 755 nm to 800 nm.

21. The method of claim 20 , wherein doping the zinc gallate spinel structure with Dy 3+ comprises mixing a dysprosium salt selected from dysprosium chloride hydrate (DyCl 3 .xH 2 O), dysprosium fluoride hydrate (DyF 3 .xH 2 O), dysprosium nitrate hydrate (Dy(NO 3 ) 3 .xH 2 O), dysprosium acetate hydroxide ((CH 3 CO 2 ) 7 Dy 3 (OH) 2 ), dysprosium bromide hydrate (DyBr 3 .xH 2 O), and dysprosium sulfate hydrate (Dy 2 (SO 4 ) 3 .xH 2 O) with said divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in said method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Dy 3+ .

22. The method of claim 2 , further comprising annealing of the divalent metal gallate spinel after being doped with a dopant selected from the group consisting of Mn, Cr, Eu, Dy, and combinations thereof.

23. The method of claim 22 , wherein the annealing of the divalent metal gallate spinel is conducted at a temperature ranging from 800° C. to 1000° C. for a time ranging from 15 minutes to 2 hours.

24. The method of claim 1 , wherein reacting of the divalent metal-containing salt and the gallium-containing salt with the supply of fermentative or thermophilic bacteria is conducted at a temperature ranging from 45° C. to 90° C.

25. The method of claim 1 , wherein the divalent metal gallate spinel structure produces white light.

26. A method of forming a structure for emitting white light, the method comprising:

forming a first phosphor of a first doped zinc gallate spinel structure that is nucleated by a first fermentation with a first thermophilic bacteria and first annealing, wherein the first phosphor emits a first wavelength of red light ranging from 570 nm to 750 nm;

forming a second phosphor of a second doped zinc gallate spinel structure that is nucleated by a second fermentation with a second thermophilic bacteria and a second annealing, wherein the second phosphor emits a wavelength of green light ranging from 495 nm to 570 nm;

forming a third phosphor of a third zinc gallate spinel structure that is nucleated by a third fermentation with a third thermophilic bacteria, wherein the third phosphor emits a wavelength of blue light ranging from 400 nm to 495 nm; and

mixing at least the first phosphor, second phosphor and third phosphor to form the structure for emitting the white light.

27. The method of claim 26 , wherein at least one of the first annealing and second annealing for forming at least one of the first phosphor or the second phosphor comprises annealing at a temperature ranging from 800° C. to 1000° C. for a time ranging from 15 minutes to 2 hours.

28. The method of claim 26 , wherein at least one of the first doped zinc gallate spinel structure, the second doped zinc gallate spinel structure, and the third doped zinc gallate structure comprises a zinc gallate that is nucleated from a mixture of a zinc-containing salt and a gallium-containing salt in the presence of the thermophilic bacteria, wherein reaction between the zinc-containing salt and the gallium-containing salt is not a reduction type reaction.

29. The method of claim 26 , wherein the zinc-containing salt is selected from zinc chloride (ZnCl 2 ), zinc bromide (ZnBr 2 ), zinc nitrate hydrate (Zn(NO 3 ) 2 .xH 2 O), zinc sulfate hydrate (ZnSO 4 .xH 2 O), zinc phosphate (Zn 3 (PO 4 ) 2 ), zinc acetate hydrate ((CH 3 CO 2 ) 2 Zn).xH 2 O), zinc stearate ([CH 3 (CH 2 ) 16 COO] 2 Zn), zinc fluoride (ZnF 2 ), zinc iodide (ZnI 2 ), zinc methoxide (C 2 H 6 O 2 Zn), zinc acrylate ((H 2 C═CHCO 2 ) 2 Zn), or combinations thereof, and the gallium-containing salt comprises gallium chloride (GaCl 3 ), gallium chloride (GaCl 2 ), gallium nitrate hydroxide (GaNO 3 .xH 2 O), gallium fluoride (GaF 3 ), gallium iodide (GaI 3 ), gallium bromide (GaBr 3 ), gallium sulfate hydrate (GaSO 4 .xH 2 O), and combinations thereof.

30. The method of claim 26 , wherein the second doped zinc gallate spinel structure is doped with Mn 2+ dopant, wherein the Mn 2+ dopant is introduced to the zinc gallate by mixing a manganese salt selected from manganese chloride hydrate(MnCl 2 .xH 2 O), manganese nitrate hydrate (Mn(NO 3 ) 2 .xH 2 O), manganese sulfate hydrate (MnSO 4 .xH 2 O), manganese iodide (MnI 2 ), manganese bromide (MnBr 2 ), manganese fluoride (MnF 3 ), manganese acetate hydrate (Mn(CH 3 COO) 2 .xH 2 O), and manganese carbonate (MnCO 3 ) with a divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in accordance with the method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Mn 2+ .

31. The method of claim 26 , wherein the first doped zinc gallate spinel structure is doped with Cr 3+ dopant, wherein the Cr 3+ dopant is introduced to the first doped zinc gallate spinel structure dopant by mixing a chromium salt selected from chromium chloride hydrate (CrCl 3 .xH 2 O), chromium nitrate hydrate (Cr(NO 3 ) 3 .xH 2 O), chromium acetate hydroxide ((CH 3 CO 2 ) 7 Cr 3 (OH) 2 ), chromium sulfate hydrate (Cr 2 (SO 4 ) 3 .xH 2 O), chromium fluoride hydrate (GaF 3 .xH 2 O), chromium iodide hydrate (CrI 3 .xH 2 O), chromium bromide hydrate (CrBr 3 .xH 2 O), and chromium phosphate hydrate (Cr(PO 4 ).xH 2 O) with a divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in accordance with the method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Cr 3+ .

32. The method of claim 26 , wherein the first doped zinc gallate spinel structure is doped with Eu + dopant, wherein the Eu 3+ dopant is introduced to the first doped zinc gallate spinel structure dopant by mixing a europium salt selected from europium chloride hydrate (EuCl 3 .xH 2 O), europium fluoride hydrate (EuF 3 .xH 2 O), europium nitrate hydrate (Eu(NO 3 ) 3 .xH 2 O), europium acetate hydroxide ((CH 3 CO 2 ) 7 Eu 3 (OH) 2 ), europium bromide hydrate (EuBr 3 .xH 2 O), and europium sulfate hydrate (Eu 2 (SO 4 ) 3 .xH 2 O) with a divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in accordance with the method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal-containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Eu 3+ .

33. The method of claim 28 further comprising forming a fourth phosphor of a fourth doped zinc gallate spinel structure with Dy 3+ dopant and the wavelength of light emission for the fourth doped zinc gallate spinel is in a wavelength ranging from 450 nm to 510 nm, or a wavelength ranging from 560 nm to 610 nm, or a wavelength ranging from 660 nm to 720 nm or a wavelength ranging from 755 nm to 800 nm.

34. The method of claim 33 , wherein doping of the zinc gallate spinel structure with Dy 3+ comprises mixing a dysprosium salt selected from dysprosium chloride hydrate (DyCl 3 .xH 2 O), dysprosium fluoride hydrate (DyF 3 .xH 2 O), dysprosium nitrate hydrate (Dy(NO 3 ) 3 .xH 2 O), dysprosium acetate hydroxide ((CH 3 CO 2 ) 7 Dy 3 (OH) 2 ), dysprosium bromide hydrate (DyBr 3 .xH 2 O), and dysprosium sulfate hydrate (Dy 2 (SO 4 ) 3 .xH 2 O) with a divalent metal-containing salt, gallium-containing salt, and supply of fermentative or thermophilic bacteria in accordance with the method of forming a metal gallate spinel structure in claim 1 , wherein said divalent metal- containing salt is a zinc-containing salt, to produce said zinc gallate spinel doped with Dy 3+ .

35. A white light emitting structure comprising:

a first zinc gallate spinel doped with chromium or europium that provides a red light emitting phosphor;

a second zinc gallate spinel doped with manganese that provides a green light emitting phosphor;

a third zinc gallate spinel that provides a blue light emitting phosphor; and

a transparent substrate, wherein the first zinc gallate spinel, the second zinc gallate spinel, and

the third zinc gallate spinel are distributed as a mixture of said first, second, and third zinc gallate spinels on or within the transparent substrate.

36. The white light emitting structure of claim 35 , wherein said mixture is a homogeneous mixture.