Mesoscopic solar cell based on perovskite light absorption material and method for making the same

Abstract

A method for preparing a mesoscopic solar cell based on perovskite light absorption materials, the method including 1) preparing a hole blocking layer on a conductive substrate; 2) preparing and sintering a mesoporous nanocrystalline layer, an insulation separating layer, and a hole collecting layer on the hole blocking layer in order; and 3) drop-coating a precursor solution on the hole collecting layer, and allowing the precursor solution to penetrate pores of the mesoporous nanocrystalline layer via the hole collecting layer from top to bottom, and drying a resulting product to obtain a mesoscopic solar cell.

Claims

1. A method for preparing a mesoscopic solar cell, the method comprising: 1) preparing a hole blocking layer on a conductive substrate; 2) preparing and sintering a mesoporous nanocrystalline layer, an insulation separating layer, and a hole collecting layer on the hole blocking layer in order; and 3) drop-coating a precursor solution of a perovskite semiconductor material on a top of the hole collecting layer, and allowing the precursor solution to diffuse from the top of the hole collecting layer and successively fill the hole collecting layer, the insulation separating layer, and the mesoporous nanocrystalline layer; and 4) drying a resulting product to obtain a mesoscopic solar cell.

2. The method for claim 1, wherein the mesoporous nanocrystalline layer and the insulation separating layer are mesoporous inorganic nano oxide films.

3. The method for claim 2, wherein the mesoporous nanocrystalline layer, the insulation separating layer, and the hole collecting layer are prepared layer by layer by screen-printing or doctor-blading.

4. The method for claim 3, further comprising filling a p-type semiconductor to optimize hole transport properties of the mesoporous nanocrystalline layer, the insulation separating layer and the hole collecting layer after 3).

5. The method for claim 2, further comprising filling a p-type semiconductor to optimize hole transport properties of the mesoporous nanocrystalline layer, the insulation separating layer and the hole collecting layer after 3).

6. The method for claim 1, wherein the mesoporous nanocrystalline layer, the insulation separating layer, and the hole collecting layer are prepared layer by layer by screen-printing or doctor-blading.

7. The method for claim 1, further comprising filling a p-type semiconductor to optimize hole transport properties of the mesoporous nanocrystalline layer, the insulation separating layer and the hole collecting layer after 3).

8. The method of claim 1, wherein the insulation separating layer comprising the perovskite semiconductor material functions as a hole transport layer between the mesoporous nanocrystalline layer and the hole collecting layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described hereinbelow with reference to accompanying drawings, in which the sole FIGURE is a schematic view of a mesoscopic solar cell based on perovskite light absorption materials of an exemplary embodiment of the invention.

(2) In the FIGURE, the following reference numbers are used: 1. Conductive substrate; 2. Hole blocking layer; 3. Mesoporous nanocrystalline layer; 4. Insulation separating layer; 5. Hole collecting layer.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(3) For further illustrating the invention, experiments detailing an epoxy caulking adhesive are described below. It should be noted that the following examples are intended to describe and not to limit the invention.

(4) Structure of a mesoscopic solar cell of the invention is illustrated in the sole FIGURE, where the cell comprises, from top to bottom, a conductive substrate 1, a hole blocking layer 2, a mesoporous nanocrystalline layer 3, an insulation separating layer 4, and a hole collecting layer 5.

(5) The mesoporous nanocrystalline layer 3, the insulation separating layer 4 and the hole collecting layer 5 are filled with perovskite semiconductor materials. The mesoporous nanocrystalline layer 3 becomes an active light absorption layer after being filled with the perovskite semiconductor materials, and the insulation separating layer 4 becomes a hole transport layer after being filled with the perovskite semiconductor materials.

(6) In addition, the mesoporous nanocrystalline layer 3 and the insulation separating layer 4 are nano oxide films. For example, the nano oxide film is selecting from the group of titania, zirconia, alumina Stannum, Zinc, nickel and silica.

(7) Preferably, the mesoporous nanocrystalline layer, the insulation separating layer, and the hole collecting layer are prepared by screen-printing layer by layer.

(8) After sintering, the mesoporous nanocrystalline layer filled with the perovskite semiconductor materials becomes an active mesoporous nanocrystalline layer as the photoanode of the cell, and the insulation separating layer filled with the perovskite semiconductor materials becomes the hole transport layer transporting holes to the hole collecting layer.

(9) After being filled with the perovskite semiconductor materials, the insulation separating layer being the nano oxide film can replace a conventional organic p-type semiconductor material and operates as a hole transport layer of the cell due to its hole transport capability. Moreover, the invention uses comparatively cheap materials, such as mesoporous carbon, as the hole collecting layer, and utilizes hole transport property of the perovskite semiconductor materials to transport holes to the hole collecting layer, which avoid the use of the organic p-type material.

(10) A method for preparing the mesoscopic solar cell of the invention will be described in details hereinafter with reference to specific examples:

Example 1

(11) Firstly conductive glass is used as the conductive substrate 1, then a compact titania layer 2 (with a thickness of 50 nm, for example) is deposited on the substrate, and finally a titania mesoporous nanocrystalline layer 3, a zirconia insulation separating layer 4, a carbon-electrode hole collecting layer 5 are sequentially prepared by screen-printing from the bottom to the top.

(12) For example, the titania layer has a grain size of 18 nm with a thickness of around 1 μm, and the insulation separating zirconia layer has a grain size of 20 nm with a thickness of 1 μm. The carbon-electrode hole collecting layer is a mesoporous conductive film made of graphite and carbon black with a thickness of approximately 10 μm. Certain amount (for example 4 μL) of methylamine lead iodine (CH.sub.3NH.sub.3PbI.sub.3) precursor solution (30 wt. %) is added on the mesoporous conductive film drop by drop, kept for 1 minute until it sufficiently penetrates in the titania mesoporous nanocrystalline layer, and finally dried at a certain temperature (for example 50° C.). Test results indicate that the obtained solar cell has an efficiency of 6.64% under simulated sunlight of 100 mW/cm.sup.2.

Example 2

(13) Firstly conductive glass is used as the conductive substrate 1, then a compact titania layer 2 (with a thickness of 50 nm, for example) is deposited on the substrate, and finally a titania mesoporous nanocrystalline layer 3, an alumina insulation separating layer 4, a carbon-electrode hole collecting layer 5 are sequentially prepared by screen-printing from the bottom to the top.

(14) For example, the titania layer has a grain size of 18 nm with a thickness of around 1 μm, and the insulation separating alumina layer has a grain size of 20 nm with a thickness of 1 μm. The carbon-electrode hole collecting layer is a mesoporous conductive film made of graphite and carbon black with a thickness of approximately 10 μm. Certain amount (for example 4 μL) of methylamine lead iodine (CH.sub.3NH.sub.3PbI.sub.3) precursor solution (30 wt. %) is added on the mesoporous conductive film drop by drop, kept for 1 minute until it sufficiently penetrates in the titania mesoporous nanocrystalline layer, and finally dried at a certain temperature (for example 50° C.). Test results indicate that the obtained solar cell has an efficiency of 6.03% under simulated sunlight of 100 mW/cm.sup.2.

Example 3

(15) Firstly conductive glass is used as the conductive substrate 1, then a compact titania layer 2 (with a thickness of 50 nm, for example) is deposited on the substrate, and finally a titania mesoporous nanocrystalline layer 3, a zirconia insulation separating layer 4, a carbon-electrode hole collecting layer 5 are sequentially prepared by screen-printing from the bottom to the top.

(16) For example, the titania layer has a grain size of 18 nm with a thickness of around 1 μm, and the insulation separating zirconia layer has a grain size of 20 nm with a thickness of 1 μm. The carbon-electrode hole collecting layer is a mesoporous conductive film made of graphite and carbon black with a thickness of approximately 10 μm. Certain amount (for example 4 μL) of methylamine lead iodine/bromide (CH.sub.3NH.sub.3PbI.sub.2Br) precursor solution (30 wt. %) is added on the mesoporous conductive film drop by drop, kept for 1 minute until it sufficiently penetrates in the titania mesoporous nanocrystalline layer, and finally dried at a certain temperature (for example 50° C.). Test results indicate that the obtained solar cell has an efficiency of 5.87% under simulated sunlight of 100 mW/cm.sup.2.

Example 4

(17) Firstly conductive glass is used as the conductive substrate 1, then a compact titania layer 2 (with a thickness of 50 nm, for example) is deposited on the substrate, and finally a titania mesoporous nanocrystalline layer 3, a zirconia insulation separating layer 4, a indium-tin-oxide-electrode hole collecting layer 5 are sequentially prepared by screen-printing from the bottom to the top.

(18) For example, the titania layer has a grain size of 18 nm with a thickness of around 1 μm, and the insulation separating zirconia layer has a grain size of 20 nm with a thickness of 1 μm. The indium-tin-oxide-electrode hole collecting layer is a mesoporous conductive film made of indium tin oxide nanocrystalline and having a thickness of approximately 10 μm. Certain amount (for example 4 μL) of methylamine lead iodine (CH.sub.3NH.sub.3PbI.sub.3) precursor solution (30 wt. %) is added on the mesoporous conductive film drop by drop, kept for 1 minute until it sufficiently penetrates in the titania mesoporous nanocrystalline layer, and finally dried at a certain temperature (for example 50° C.). Test results indicate that the obtained solar cell has an efficiency of 5.15% under simulated sunlight of 100 mW/cm.sup.2.

(19) In the above-mentioned examples, the conductive substrate 1 is preferably conductive glass or conductive plastics. The hole blocking layer 2 is an inorganic metal oxide film, and preferably a compact titania film with a thickness of 50 nm, but not limited to the titania film, and the thickness can be adjusted as required (for example 50 nm-10 μm). The mesoporous nanocrystalline layer 3 and the insulation separating layer 4 are nano oxide films, the mesoporous nanocrystalline layer 3 is preferably titania mesoporous nanocrystalline layer, but not limited to titania, the grain size also is not limited to 18 nm, the insulation separating layer 4 is preferably zirconia, and the grain size and thickness also are not limited to the above examples, and can be adjusted as required (for example 50 nm-10 μm). The hole collecting layer 5 is an electrode layer made of mesoporous materials, and preferably high work function electrode materials comprising carbon, indium tin oxide and so on, but not limited to these materials.

(20) A chemical formula of the perovskite semiconductor material is ABX.sub.3, where A is selecting from the group of alkylamine and an alkali element, B is selecting from the group of lead and tin, and X is selecting from the group of iodine, bromide and chlorine, and preferably methylamine lead iodine (CH.sub.3NH.sub.3PbI.sub.3).

(21) While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.