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EP-4741405-A1 - ENHANCED PEROVSKITE MATERIALS FOR PHOTOVOLTAIC DEVICES

EP4741405A1EP 4741405 A1EP4741405 A1EP 4741405A1EP-4741405-A1

Abstract

A perovskite material that has a perovskite crystal lattice having a formula of C x M y X z , where x, y, and z , are real numbers. Bulky organic cations reside near a surface or a grain boundary of the perovskite crystal lattice. C includes one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, methylammonium, formamidinium, guanidinium, and ethene tetramine. M includes one or more metals each selected from the group consisting of Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr and combinations thereof. X includes one or more anions each selected from the group consisting of halides, sulfides, selenides, and combinations thereof.

Inventors

  • IRWIN, MICHAEL, D.
  • HOLLAND, MICHAEL
  • ANDERSON, NICHOLAS

Assignees

  • CubicPV Inc.

Dates

Publication Date
20260513
Application Date
20191108

Claims (15)

  1. 1. A perovskite material comprising: a perovskite crystal lattice having a formula of C x M y X z ; and alkyl polyammonium cations dispersed within or at a surface of the perovskite crystal lattice; wherein: x, y, and z, are real numbers; C comprises one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, methylammonium, formamidinium, guanidinium, and ethene tetramine; M comprises one or more metals each selected from the group consisting of Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr and combinations thereof; and X comprises one or more anions each selected from the group consisting of halides, pseudohalides, chalcogenides, and combinations thereof.
  2. A method for depositing perovskite material comprising: depositing a lead salt precursor onto a substrate to form a lead salt thin film, wherein the lead salt precursor comprises a lead salt and an alkyl polyammonium salt; depositing a second salt precursor onto the lead salt thin film to form a perovskite precursor thin film; and annealing the substrate and perovskite precursor thin film to form a perovskite material.
  3. The perovskite material of claim 1, wherein the alkyl polyammonium cations comprise 1,4-diammonium butane, 1,8 diammonium octane, bis(4-aminobutyl)amine, or tris(4-aminobutyl)amine; or the method of claim 2, wherein the alkyl polyammonium salt comprises 1,4-diammonum butane, 1,8 diammonium octane, bis(4-aminobutyl)amine, or tris(4-aminobutyl)amine.
  4. The perovskite material of claim 1 or claim 3, wherein the alkyl polyammonium cations have a concentration between 1 mol % and 20 mol % in the perovskite material; and optionally or preferably wherein the alkyl polyammonium cations have a concentration between 1 mol % and 5 mol % in the perovskite material; and further optionally or preferably wherein the alkyl polyammonium cations have a concentration of approximately 5 mol % in the perovskite material; or the method of claim 2 or claim 3, wherein the alkyl polyammonium salt has a concentration between 1 mol % and 20 mol %; and optionally or preferably wherein the alkyl polyammonium salt has a concentration between 1 mol % and 5 mol %; and further optionally or preferably wherein the alkyl polyammonium salt has a concentration of approximately 5 mol %.
  5. The perovskite material of any preceding perovskite material claim, wherein the perovskite material crystal lattice has a cubic structure.
  6. The perovskite material of any perovskite material preceding claim, wherein C comprises formamidinium, M comprises lead, and X comprises iodide.
  7. The perovskite material of claim 6, wherein the ammonium groups of the alkyl polyammonium cations substitute for formamidinium ions within the perovskite crystal lattice.
  8. The method of claim 2, wherein the lead salt is selected from the group consisting of lead (II) iodide, lead (II) thiocyanate, lead (II) chloride, lead (II) bromide, and combinations thereof; and optionally or preferably wherein the lead salt comprises lead (II) iodide.
  9. The method of claim 2, wherein the second salt precursor comprises a salt selected from the group consisting of formamidinium iodide, formamidinium thiocyanate, guanidinium thiocyanate, and combinations thereof; and optionally or preferably wherein the second salt precursor comprises formamidinium iodide.
  10. The method of claim 2, wherein the lead salt precursor contains one or more additives selected from the group consisting of an amino acid, 5-aminovaleric acid hydroiodide, 1,8-diiodooctane, 1,8-dithiooctane, formamidinium halide, acetic acid, trifluoroacetic acid, a methylammonium halide, water, and combinations thereof.
  11. The method of claim 2, wherein the lead salt precursor comprises a 90:10 mole ratio of PbI 2 to PbCl 2 dissolved in anhydrous dimethylformamide.
  12. The method of claim 2, wherein annealing occurs: (i) at a temperature greater than or equal to 50°C and less than or equal to 300°C; and/or (ii) at an absolute humidity greater than or equal to 0 g H 2 O/m 3 air and less than or equal to 20 g H 2 O/m 3 air, and optionally or preferably at an absolute humidity between about 4 and 7 g H 2 O/m 3 air.
  13. A method for depositing perovskite material comprising: depositing a lead salt precursor onto a substrate to form a lead salt thin film; depositing an alkyl polyammonium salt precursor onto the lead salt thin film; depositing a third salt precursor onto the lead salt thin film to form a perovskite precursor thin film; and annealing the substrate and perovskite precursor thin film to form a perovskite material.
  14. The method of claim 15, wherein: the lead salt precursor comprises lead (II) iodide; the third salt precursor comprises formamidinium iodide.
  15. The method of claim 15, wherein: the lead salt precursor comprises a 90:10 mole ratio of PbI 2 to PbCl 2 dissolved in anhydrous dimethylformamide; the lead salt precursor comprises as much as 10 mol % cesium; and annealing occurs at a temperature greater than or equal to 50° C. and less than or equal to 300° C.

Description

This application claims priority to U.S. Provisional Patent Application No. 62/770,313 filed November 21, 2018 and entitled "Enhanced Perovskite Materials for Photovoltaic Devices." BACKGROUND Use of photovoltaics (PVs) to generate electrical power from solar energy or radiation may provide many benefits, including, for example, a power source, low or zero emissions, power production independent of the power grid, durable physical structures (no moving parts), stable and reliable systems, modular construction, relatively quick installation, safe manufacture and use, and good public opinion and acceptance of use. PVs may incorporate layers of perovskite materials as photoactive layers that generate electric power when exposed to light. Some photoactive layers may be degraded by environmental factors including temperature, humidity, and oxidation. Therefore, improvements to perovskite material durability and efficiency are desirable. The features and advantages of the present disclosure will be readily apparent to those skilled in the art. While numerous changes may be made by those skilled in the art, such changes are within the spirit of the invention. SUMMARY To address the foregoing problems with existing solutions, disclosed are enhanced perovskite materials and methods for forming such materials. According to some embodiments, a perovskite material has a perovskite crystal lattice having a formula of CxMyXz, where x, y, and z, are real numbers. Bulky organic cations reside near a surface or a grain boundary of the perovskite crystal lattice. C includes one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, ammonium, formamidinium, guanidinium, and ethene tetramine. M includes one or more metals each selected from the group consisting of Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr and combinations thereof. X includes one or more anions each selected from the group consisting of halides, pseudohalides, chalcogenides (tellurides, oxides, sulfides, and selenides), and combinations thereof. In particular embodiments, a tail group of at least one bulky organic cations is not chemically connected to the surfaces or grain boundaries of the perovskite material. In particular embodiments, the bulky organic cations reside less than 50 nm into the perovskite material crystal lattice from the surfaces or grain boundaries of the perovskite material crystal lattice. In particular embodiments, the bulky organic cation is selected from the group consisting of n-butylammonium; benzylammonium; butane-1,4-diammonium; pentylammonium; hexylammonium; poly(vinylammonium); phenylethylammonium; 3-phenyl-1-propylammonium; 4-phenyl-1-butylammonium; 1,3-dimethylbutylammonium; 3,3-dimethylbutylammonium, and 1-octylammonium, and combinations thereof. In particular embodiments, the bulky organic cation comprises 1-butylammonium. In particular embodiments, the bulky organic cation comprises 1-hexylammonium. In particular embodiments, the bulky organic cation comprises 1-octylammonium. In particular embodiments, the bulky organic cation comprises benzylammonium. In particular embodiments, the perovskite material crystal lattice has a cubic structure. According to some embodiments, a perovskite material includes a formamidinium lead iodide perovskite material. Benzylammonium cations reside near a surface or a grain boundary of the formamidinium lead iodide perovskite material. In particular embodiments, at least one benzyl group of the benzylammonium cations is not chemically connected to the grain boundaries or surfaces of the formamidinium lead iodide perovskite material. In particular embodiments, the benzylammonium cations reside less than 50 nm into the formamidinium lead perovskite material from the surfaces or the grain boundaries of the formamidinium lead perovskite material. In particular embodiments, the formamidinium lead iodide perovskite material has a cubic crystal structure. According to some embodiments, a method for depositing a perovskite material includes depositing a lead salt precursor onto a substrate to form a lead salt thin film, depositing a bulky organic cation solution onto the lead salt thin film, depositing a second salt precursor onto the lead salt thin film to form a perovskite precursor thin film, and annealing the substrate to form a perovskite material. In particular embodiments, the bulky organic cation solution comprises a bulky organic cation selected from the group consisting of n-butylammonium; benzylammonium; butane-1,4-diammonium; pentylammonium; hexylammonium; poly(vinylammonium); phenylethylammonium; 3-phenyl-1-propylammonium; 4-phenyl-1-butylammonium; 1,3-dimethylbutylammonium; 3,3-dimethylbutylammonium, 1-octylammonium, ammonium functionalized perylenes, and combinations thereof. In particular embodiments, the bulky organic cation solution comprises 1-butylammonium. In particular embodiments, the