KR20200031388A - Organic-inorganic complex solar cell - Google Patents

Abstract

The present specification provides an organic-inorganic complex solar cell comprising: a first electrode; a first common layer including a metal oxide including tin provided on the first electrode; a light absorbing layer including a compound having a perovskite structure provided on the first common layer; and a second electrode including a carbon material provided on the light absorbing layer.

Description

Organic-Inorganic Composite Solar Cell {ORGANIC-INORGANIC COMPLEX SOLAR CELL}

This specification relates to an organic-inorganic composite solar cell.

In order to solve the global environmental problems caused by the depletion of fossil energy and its use, research on renewable and clean alternative energy sources such as solar energy, wind power, and hydropower has been actively conducted. Among them, interest in solar cells that directly change electrical energy from solar light is increasing. Here, a solar cell means a battery that absorbs light energy from sunlight and generates current-voltage using a photovoltaic effect that generates electrons and holes.

The organic-inorganic composite perovskite material has recently been spotlighted as an organic-inorganic composite solar cell light absorbing material because of its high absorption coefficient and easy synthesis through solution process.

However, in the case of an organic-inorganic composite solar cell using a conventional perovskite material, despite high efficiency, the metal electrode applied to the upper electrode reacts with halogen elements in the perovskite light absorbing layer, thereby conducting electricity. And long-term driving stability. In addition, the vacuum deposition method for introducing the metal electrode has a problem that the cost increases when applied to a roll-to-roll process for commercialization.

Therefore, studies on other upper electrodes capable of improving durability and fairness are needed.

Adv. Mater. 2014, 26, 4991-4998

The present specification provides an organic-inorganic composite solar cell.

An exemplary embodiment of the present specification is a first electrode;

A first common layer comprising a metal oxide containing tin provided on the first electrode;

A light absorbing layer comprising a compound of perovskite structure provided on the first common layer; And

An organic-inorganic composite solar cell including a second electrode including a carbon material provided on the light absorbing layer.

The organic-inorganic composite solar cell according to an exemplary embodiment of the present specification is excellent in long-term stability at room temperature and high temperature.

In addition, the organic-inorganic composite solar cell according to an exemplary embodiment of the present specification is capable of absorbing a wide spectrum of light, reducing light energy loss and increasing energy conversion efficiency.

1 and 2 are diagrams illustrating the structure of an organic-inorganic composite solar cell according to an exemplary embodiment of the present specification.
3 is a view showing a scanning electron microscope (SEM) image of a second electrode cross-section prepared in Example 1.
4 is a view showing the result of measuring the high temperature storage stability of the organic-inorganic composite solar cell manufactured in one embodiment of the present specification.

Hereinafter, the present specification will be described in detail.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, not to exclude other components, unless otherwise stated.

In the present specification, when it is said that a member is positioned “on” another member, this includes not only the case where one member abuts another member, but also the case where another member is present between two members.

An exemplary embodiment of the present specification is a first electrode;

A first common layer comprising a metal oxide containing tin provided on the first electrode;

A light absorbing layer comprising a compound of perovskite structure provided on the first common layer; And

An organic-inorganic composite solar cell including a second electrode including a carbon material provided on the light absorbing layer.

1 shows an organic-inorganic composite solar cell according to an exemplary embodiment of the present specification. Specifically, an organic-inorganic composite solar cell in which the first electrode 10, the first common layer 20, the light absorbing layer 30, and the second electrode 50 are sequentially stacked is illustrated.

In one embodiment of the present specification, the metal oxide containing tin is SnO ₂ (tin oxide), Sb: SnO ₂ (antimony-doped tin oxide), BaSnO ₃ (barium tin trioxide) and La: BaSnO ₃ (lanthanum) -doped barium tin trioxide).

In one embodiment of the present specification, the metal oxide containing tin is SnO ₂ (tin oxide), Sb: SnO ₂ (antimony-doped tin oxide), BaSnO ₃ (barium tin trioxide) and La: BaSnO ₃ (lanthanum) -doped barium tin trioxide).

When the first common layer includes a metal oxide containing tin, the photoelectric conversion efficiency and long-term stability are superior to those of other metal oxides other than tin (eg, Ti oxide, Zn oxide).

In one embodiment of the present specification, the metal oxide containing tin is included in the form of nanoparticles in the first common layer. When included as a nanoparticle, there is an effect that a low temperature process of 150 ° C or less is possible.

In this specification, "nanoparticle" means that the particle size is in the nm range. For example, the “nanoparticle” may have a particle size of 1 nm to 990 nm.

In one embodiment of the present specification, the thickness of the first common layer is 5 nm to 100 nm.

When the thickness of the first common layer satisfies the above range, the short-circuit current density (Jsc) and the fill factor increase, thereby increasing the photoelectric conversion efficiency of the battery.

In one embodiment of the present specification, the first common layer is an electron transport layer.

In one embodiment of the present specification, the first common layer is sputtering, E-Beam, thermal deposition, atomic layer deposition (ALD), spin coating, slit coating, screen printing, inkjet printing, spray coating, doctor blade or gravure It may be formed by being applied to one surface of the first electrode using a printing method or coated in a film form.

In one embodiment of the present specification, the second electrode includes a carbon material.

Conventional organic-inorganic composite solar cells used metal as the second electrode. In this case, the metal reacts with halogen elements in the perovskite light-absorbing layer, and thus there is a problem in that electrical conductivity and long-term driving stability are lowered. In addition, the vacuum deposition method for introducing a metal has a problem that the cost increases when applied to a roll-to-roll process for commercialization.

On the other hand, in one embodiment of the present specification, by applying a carbon material as an upper electrode, the manufacturing process is simple, the process cost is reduced, and the driving stability of the battery is increased. For example, there is an effect capable of manufacturing a battery even at normal pressure.

In one embodiment of the present specification, the carbon material is carbon nanotube (CNT), graphite, graphene, graphene oxide, activated carbon, porous carbon, carbon fiber (carbon fiber), conductive carbon black (carbon black) and carbon nanowires (carbon nano wire).

In one embodiment of the present specification, the carbon material is carbon nanotube (CNT), graphite, graphene, graphene oxide, activated carbon, porous carbon, carbon fiber (carbon fiber), conductive carbon black (carbon black) and carbon nanowires (carbon nano wire).

In one embodiment of the present specification, the second electrode including the carbon material includes a first carbon material and a second carbon material different from each other,

The first carbon material includes one or more of carbon nanotube (CNT), graphite (graphite) and graphene (graphene),

The second carbon material includes conductive carbon black.

In one embodiment of the present specification, the carbon material is preferably applied with a small volume and a uniformly shaped conductive carbon material in order to facilitate physical / chemical bonding with the lower layer, due to conductivity and shape limitations. It is preferred to use more than one kind of carbon material.

Among the carbon materials, carbon nanotubes (CNT), graphite, and graphene have excellent conductivity. Accordingly, an exemplary embodiment of the present specification includes at least one of carbon nanotubes (CNT), graphite, and graphene as the first carbon material.

In one embodiment of the present specification, the first carbon material includes carbon nanotubes (CNT), graphite, or graphene.

In one embodiment of the present specification, the first carbon material includes graphite.

In one embodiment of the present specification, the electrical conductivity of the graphite is 25S / cm to 30S / cm.

In one embodiment of the present specification, the size of the graphite particles is 1 μm to 25 μm.

Among the carbon materials, the conductive carbon black has the smallest volume and is close to a sphere in three dimensions, so it can serve as a bonding material with the lower layer. Accordingly, an exemplary embodiment of the present specification includes a conductive carbon black as a second carbon material.

In one embodiment of the present specification, the size of the conductive carbon black particles is 10 nm to 50 nm.

In one embodiment of the present specification, the electrical conductivity of the conductive carbon black is 2S / cm to 4S / cm.

In one embodiment of the present specification, the content of the second carbon material is 30 to 60 parts by weight compared to 100 parts by weight of the first carbon material.

When the content of the second carbon material satisfies the above range, the size of the particles forming the second electrode is appropriately adjusted, and adhesion with the lower layer can be improved. This facilitates charge transfer in the vertical direction (with the lower layer). Accordingly, when the above range is satisfied, the short-circuit current density (Jsc) and the filling factor (Fill factor) are increased to increase the photoelectric conversion efficiency of the battery.

In one embodiment of the present specification, the particle size of the carbon material formed by the second electrode is 15 μm or less.

When the content of the second carbon material satisfies the above range, the short-circuit current density (Jsc) and the filling factor (Fill factor) is increased to increase the photoelectric conversion efficiency of the battery.

In one embodiment of the present specification, the second electrode including the carbon material further includes a binder.

In one embodiment of the present specification, the binder may be a water-soluble polymer, a photocurable resin, a thermosetting resin or a thermoplastic resin. For example, the binder is poly (meth) acrylic, polycarbonate, polystyrene, polyarylene, polyurethane, styrene-acrylonitrile, polyvinylidenefluoride, polyvinylidene fluoride, such as polymethyl methacrylate Oride-based derivatives, ethyl cellulose, etc. may be used, but is not limited thereto.

In one embodiment of the present specification, only one type of the binder may be used, or two or more types of the binder may be used together.

In one embodiment of the present specification, by including the binder, adhesion to the lower layer, hardness of the electrode, and driving stability of the battery can be improved.

In one embodiment of the present specification, the lower layer means a light absorbing layer or a second common layer.

In one embodiment of the present specification, the content of the binder is 15 to 100 parts by weight compared to 100 parts by weight of the carbon material. That is, the content of the binder is 15 to 100 parts by weight compared to 100 parts by weight of the sum of the first carbon material and the second carbon material. Specifically, the content of the binder is 30 to 100 parts by weight compared to 100 parts by weight of the carbon material. More specifically, the content of the binder is 50 to 90 parts by weight compared to 100 parts by weight of the carbon material.

In one embodiment of the present specification, the light absorbing layer includes a fluorine-based surfactant.

In one embodiment of the present specification, the fluorine-based surfactant means a surface-active substance containing fluorine.

In one embodiment of the present specification, the fluorine-based surfactant may be used without limitation as long as it is a material used in the art. Specifically, the main chain is a hydrophilic group, a lipophilic group, a fluoro group, and a perfluoroalkyl (perfluoro) alkyl) group may be an oligomer, but is not limited thereto.

In one embodiment of the present specification, the fluorine-based surfactant may be represented by Formula A below.

[Formula A]

In the formula (A), x and y are each an integer of 1 to 10.

Specifically, Dupont FS-31, Zonyl FS-300, DIC RS-72-K or 3M FC-4430 may be used as the fluorine-based surfactant.

According to an exemplary embodiment of the present specification, the fluorine-based surfactant is included in the light absorbing layer, and thus, when forming the light absorbing layer, the driving stability of the battery may be improved without deteriorating electrical characteristics.

In one embodiment of the present specification, the light absorbing layer includes a fluorine-based surfactant in an amount of 0.005 wt% to 0.5 wt% based on the mass of the light absorbing layer.

In one embodiment of the present specification, the light absorbing layer includes a compound having a perovskite structure.

In one embodiment of the present specification, the compound of the perovskite structure is represented by any one of the following Chemical Formulas 1 to 3.

[Formula 1]

R1M1X1 ₃

[Formula 2]

R2 _a R3 _(1-a) M2X2 _z X3 _(3-z)

[Formula 3]

R4 _b R5 _c R6 _d M3X4 _{z '} X5 _(3-z')

In Chemical Formulas 1 to 3,

R2 and R3 are different from each other,

R4, R5 and R6 are different from each other,

R1 to R6 are each independently C _n H _{2n + 1} NH ₃ ⁺ , NH ₄ ⁺ , HC (NH ₂ ) ₂ ⁺ , Cs ⁺ , Rb ⁺ , NF ₄ ⁺ , NCl ₄ ⁺ , PF ₄ ⁺ , PCl ₄ ⁺ , CH ₃ PH ₃ ⁺ , CH ₃ AsH ₃ ⁺ , CH ₃ SbH ₃ ⁺ , PH ₄ ⁺ , AsH ₄ ⁺ and SbH ₄ ⁺ is a monovalent cation selected from,

M1 to M3 are the same as or different from each other, and each independently Cu ^{2 +} , Ni ^{2 +} , Co ^{2 +} , Fe ^{2 +} , Mn ²⁺ , Cr ^{2 +} , Pd ^{2 +} , Cd ^{2 +} , Ge ^{2 +} , Sn ^{2 +} , Bi ^{2 +} , Pb ^{2 +} and a divalent metal ion selected from Yb ^{2 +} ,

X1 to X5 are the same as or different from each other, and each independently a halogen ion,

n is an integer from 1 to 9,

a is a real number of 0 <a <1,

b is a real number of 0 <b <1,

c is a real number in 0 <c <1,

d is a real number of 0 <d <1,

b + c + d is 1,

z is a real number of 0 <z <3,

z 'is a real number of 0 <z' <3.

In one embodiment of the present specification, the compound of the perovskite structure of the light absorbing layer may include a single cation. In the present specification, a single cation means that one type of monovalent cation is used. That is, in Formula 1, R1 means that only one type of monovalent cation was selected. For example, R1 in Chemical Formula 1 is C _n H _{2n + 1} NH ₃ ⁺ , and n may be an integer from 1 to 9.

In one embodiment of the present specification, the compound of the perovskite structure of the light absorbing layer may include a complex cation. In the present specification, the complex cation means that two or more kinds of monovalent cations are used. That is, in Formula 2, it is meant that a monovalent cation in which R2 and R3 are different from each other is selected, and in Formula 3, a monovalent cation in which R4 to R6 are different from each other is selected. For example, R2 in Chemical Formula 2 may be C _n H _{2n + 1} NH ₃ ⁺ , and R3 may be HC (NH ₂ ) ₂ ⁺ . In addition, R4 in Chemical Formula 3 may be C _n H _{2n + 1} NH ₃ ⁺ , R5 may be HC (NH ₂ ) ₂ ⁺ , and R6 may be Cs ⁺ .

In one embodiment of the present specification, the compound of the perovskite structure is represented by Chemical Formula 1.

 In one embodiment of the present specification, the compound of the perovskite structure is represented by Chemical Formula 2.

In one embodiment of the present specification, the compound of the perovskite structure is represented by Chemical Formula 3.

In one embodiment of the present specification, R1 to R6 are each C _n H _{2n + 1} NH ₃ ⁺ , HC (NH ₂ ) ₂ ⁺ or Cs ⁺ . At this time, R2 and R3 are different from each other, and R4 to R6 are different from each other.

In one embodiment of the present specification, R1 is CH ₃ NH ₃ ⁺ , HC (NH ₂ ) ₂ ⁺ or Cs ⁺ .

In one embodiment of the present specification, R2 and R4 are each CH ₃ NH ₃ ⁺ .

In one embodiment of the present specification, R3 and R5 are each HC (NH ₂ ) ₂ ⁺ .

In one embodiment of the present specification, R6 is Cs ⁺ .

In one embodiment of the present disclosure, the M1 to M3 are each a Pb ^{+ 2.}

In one embodiment of the present specification, X2 and X3 are different from each other.

In one embodiment of the present specification, X4 and X5 are different from each other.

In one embodiment of the present specification, X1 to X5 are F or Br, respectively.

In an exemplary embodiment of the present specification, in order that the sum of R2 and R3 becomes 1, a is a real number of 0 <a <1. Also, in order that the sum of X2 and X3 becomes 3, z is a real number of 0 <z <3.

In one embodiment of the present specification, in order for the sum of R4, R5, and R6 to become 1, b is a real number of 0 <b <1, c is a real number of 0 <c <1, and d is 0 <d <1 is a real number, and b + c + d is 1. In addition, in order that the sum of X4 and X5 becomes 3, z 'is a real number of 0 <z' <3.

In one embodiment of the present specification, the compound of the perovskite structure is CH ₃ NH ₃ PbI ₃ , HC (NH ₂ ) ₂ PbI _{3 ,} CH ₃ NH ₃ PbBr ₃ , HC (NH ₂ ) ₂ PbBr ₃ , (CH ₃ NH ₃ ) _a (HC (NH ₂ ) ₂ ) _(1-a) PbI _z Br _(3-z) or (HC (NH ₂ ) ₂ ) _b (CH ₃ NH ₃ ) _c Cs _d PbI _{z '} Br _(3-z') , a is a real number of 0 <a <1, b is a real number of 0 <b <1, c is a real number of 0 <c <1, d is a real number of 0 <d <1, b + c + d is 1, z is a real number of 0 <z <3, z 'is a real number of 0 <z'<3 .

In one embodiment of the present specification, the thickness of the light absorbing layer is 200 nm to 1500 nm.

When the thickness of the light absorbing layer satisfies the above range, there is an effect of increasing the photoelectric conversion efficiency of the battery.

In one embodiment of the present specification, the light absorbing layer may be introduced through spin coating, dip coating, inkjet printing, gravure printing, spray coating, doctor blade, bar coating, brush painting, thermal deposition, or the like.

In one embodiment of the present specification, a second common layer is included between the light absorbing layer and the second electrode.

In one embodiment of the present specification, the second common layer is a hole transport layer.

In one embodiment of the present specification, the thickness of the second common layer is 10 nm to 300 nm.

When the thickness of the second common layer satisfies the above range, the short-circuit current density (Jsc) and the filling factor (Fill factor) is increased to increase the photoelectric conversion efficiency of the battery.

In an exemplary embodiment of the present specification, the second common layer is spin coating, slit coating, dip coating, inkjet printing, gravure printing, spray coating, doctor blade, bar coating, brush painting, sputtering, atomic layer deposition (ALD) , It can be introduced through a method such as thermal evaporation.

In one embodiment of the present specification, the second common layer is poly (3,4-ethylenedioxythiophene): poly (4-styrenesulfonate) (PEDOT: PSS), 2,2 ', 7,7' -Tetrakis (N, N-di-p-methoxyphenylamine) -9,9'-spirobifluorene (2,2 ', 7,7'-tetrakis (N, N-di-p-methoxyphenylamine) -9,9'-spirobifluorene, Spiro-OMeTAD), PTAA (Poly (triaryl amine)), Copper (I) thiocyanate, Cu ₂ O, V ₂ O ₅ , NiO, etc. may be used, but is not limited thereto. .

In one embodiment of the present specification, the organic-inorganic composite solar cell has an n-i-p structure.

 In the present specification, the nip structure is a structure in which a first electrode, an electron transport layer, a light absorption layer, and a second electrode are sequentially stacked, or a first electrode, an electron transport layer, a light absorption layer, a hole transport layer, and a second electrode are sequentially stacked. It means structure.

In one embodiment of the present specification, the organic-inorganic composite solar cell may further include a substrate under the first electrode.

In one embodiment of the present specification, the substrate may be a substrate having excellent transparency, surface smoothness, ease of handling, and waterproofness. Specifically, a glass substrate, a thin glass substrate, or a plastic substrate can be used. The plastic substrate has a flexible film such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether ether ketone and polyimide in the form of a single layer or multiple layers. Can be included. However, the substrate is not limited to this, and a substrate commonly used in organic-inorganic composite solar cells may be used.

In the present specification, the first electrode may be an anode, and the second electrode may be a cathode. Further, the first electrode may be a cathode, and the second electrode may be an anode.

In one embodiment of the present specification, the first electrode is a transparent electrode, and the solar cell may absorb light through the first electrode.

In one embodiment of the present specification, when the first electrode is a transparent electrode, the first electrode is polyethylene terephthalate (PET), polyethylene naphthelate (PEN), poly, in addition to glass and quartz plates Propylene (polyperopylene, PP), polyimide (PI), polycarbonate (polycarbornate, PC), polystyrene (PS), polyoxyethlene (POM), AS resin (acrylonitrile styrene copolymer), ABS resin ( A material doped with a conductive material may be used on a flexible and transparent material such as acrylonitrile butadiene styrene copolymer, triacetyl cellulose (TAC), and polyarylate (PAR). Specifically, the first electrode is indium tin oxide (ITO), fluorine doped tin oxide (FTO), aluminum doped zinc oxide (aluminium doped zink oxide, AZO), IZO (indium tin) zinc oxide), ZnO-Ga ₂ O ₃ , ZnOAl ₂ O ₃ and antimony tin oxide (ATO), and more specifically, the first electrode may be ITO.

In one embodiment of the present specification, the first electrode may be a translucent electrode. When the first electrode is a semi-transparent electrode, it may be made of a metal such as silver (Ag), gold (Au), magnesium (Mg) or alloys thereof.

Hereinafter, examples will be described in detail to specifically describe the present specification. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not interpreted to be limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

Example 1.

A solution containing 1 wt% of tin dioxide (SnO ₂ ) in ethanol (ethanol) on a non-alkali glass substrate sputtered with tin indium oxide (ITO) was spin-coated at 2,000 rpm, and then dried at 150 ° C. for 30 minutes. Then perovskite precursor ((HC (NH ₂ ) ₂ ) _x (CH ₃ NH ₃ ) _y Cs _{1 -xy} PbI _z Br _3-z (0 <x <1, 0 <y <1, 0.8 <x Spindle coating a solution of + y <1, 0 <z <3) and 0.05wt% of a fluorine-based surfactant (3M 社, FC-4430) in dimethylformamide at 5000 rpm compared to a perovskite precursor, followed by 100 The light-absorbing layer was formed by heating at 30 ° C. Finally, the carbon electrode, which was a mixture of graphite, conductive carbon black, and ethyl cellulose (weight ratio 12: 5.5: 12.5) was coated with a doctor blade method and heated at 100 ° C. for 30 minutes. The organic-inorganic composite solar cell was completed.

FIG. 3 shows a scanning electron microscope (SEM) image of the second electrode cross section prepared in Example 1.

Referring to Figure 3, it can be seen that the particle size of the carbon material forming the second electrode is small (about 15 μm or less). This is a result of forming a second electrode by mixing graphite and conductive carbon black in an appropriate ratio. As the amount of the conductive carbon black in the second electrode is adjusted and the particle size of the carbon material decreases, the interlayer adhesion is increased and the charge transfer in the vertical direction (interlayer) is facilitated.

Comparative Example 1.

After spin coating a solution containing ₂ wt% of titanium dioxide (TiO ₂ ) in isopropyl alcohol at 2,000 rpm on an alkali-free glass substrate sputtered with tin indium oxide (ITO), dried at 150 ° C. for 30 minutes. Did. Then perovskite precursor ((HC (NH ₂ ) ₂ ) _x (CH ₃ NH ₃ ) _y Cs _1-xy PbI _z Br _3-z (0 <x <1, 0 <y <1, 0.8 <x Spindle coating a solution of + y <1, 0 <z <3) and 0.05wt% of a fluorine-based surfactant (3M 社, FC-4430) in dimethylformamide at 5000 rpm compared to a perovskite precursor, followed by 100 The light-absorbing layer was formed by heating at 30 ° C. Afterwards, 2,2 ', 7,7'-tetrakis (N, N-di-p-methoxyphenylamine) -9,9'-spirobifluorene ( After dissolving Spiro-OMeTAD in chlorobenzene, a solution containing tertiary butyl pyridine (tBP) and lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) was spin coated. An organic-inorganic composite solar cell was completed by vacuum deposition.

Comparative Example 2

After spin coating a solution containing ₂ wt% of titanium dioxide (TiO ₂ ) in isopropyl alcohol at 2,000 rpm on an alkali-free glass substrate sputtered with tin indium oxide (ITO), dried at 150 ° C. for 30 minutes. Did. Then perovskite precursor ((HC (NH ₂ ) ₂ ) _x (CH ₃ NH ₃ ) _y Cs _1-xy PbI _z Br _3-z (0 <x <1, 0 <y <1, 0.8 <x Spindle coating a solution of + y <1, 0 <z <3) and 0.05wt% of a fluorine-based surfactant (3M 社, FC-4430) in dimethylformamide at 5000 rpm compared to a perovskite precursor, followed by 100 The light-absorbing layer was formed by heating at 30 ° C. Finally, the carbon electrode, which was a mixture of graphite, carbon black, and ethyl cellulose (weight ratio 12: 5.5: 12.5) was coated with a doctor blade method and heated at 100 ° C. for 30 minutes. -Completed inorganic composite solar cell.

Comparative Example 3.

A solution containing 1 wt% of tin dioxide (SnO ₂ ) in ethanol (ethanol) on a non-alkali glass substrate sputtered with tin indium oxide (ITO) was spin-coated at 2,000 rpm, and then dried at 150 ° C. for 30 minutes. Then perovskite precursor ((HC (NH ₂ ) ₂ ) _x (CH ₃ NH ₃ ) _y Cs _{1 -xy} PbI _z Br _3-z (0 <x <1, 0 <y <1, 0.8 <x Spindle coating a solution of + y <1, 0 <z <3) and 0.05wt% of a fluorine-based surfactant (3M 社, FC-4430) in dimethylformamide at 5000 rpm compared to a perovskite precursor, followed by 100 A light absorbing layer was formed by heating at 30 ° C. Finally, an organic-inorganic composite solar cell was completed by vacuum-depositing Au.

Experimental Example 1. Photoelectric conversion efficiency measurement

The results of measuring the photoelectric conversion efficiency using the organic-inorganic composite solar cells prepared in Example 1 and Comparative Examples 1 to 3 using the ABET Sun 3000 solar simulator as a light source and a Keithley 2420 source meter are shown in Table 1 below. . In one measurement, the current was measured after applying a voltage while decreasing from 12V to 0V by 12mV per 0.1sec.

PCE
(%) J _sc
(mA / cm ² ) V _oc
(V) FF
(%) Example 1 13.8 19.1 1.00 72.0 Comparative Example 1 14.3 19.7 0.97 74.9 Comparative Example 2 14.0 19.9 1.04 67.7 Comparative Example 3 2.7 13.0 0.63 32.8

In Table 1, Voc is the open voltage, Jsc is the short-circuit current density, FF is the fill factor, and PCE is the energy conversion efficiency. The open-voltage and short-circuit current densities are the X-axis and Y-axis intercepts in the quadrant of the voltage-current density curve, respectively, and the higher these two values, the higher the efficiency of the solar cell is. In addition, the fill factor is a value obtained by dividing the maximum area of a rectangle that can be drawn inside the curve by the product of the short-circuit current density and the open voltage. The energy conversion efficiency can be obtained by dividing these three values by the intensity of the irradiated light. The higher the value, the better.

From Table 1, it can be seen that the photoelectric conversion efficiency of the organic-inorganic composite solar cell prepared in Example 1 is superior to Comparative Examples 2 and 3.

Experimental Example 2. High temperature storage stability measurement

In order to evaluate the high-temperature storage stability of the organic-inorganic composite solar cells prepared in Examples 1 and Comparative Examples 1 to 3, after storing the cells in a vacuum oven at 85 ° C., take them out every elapsed time, cool them down to room temperature, and improve the photoelectric conversion efficiency. It was measured. The photoelectric conversion efficiency measurement method is the same as in Experimental Example 1.

4 shows the results of measuring the high temperature storage stability of the organic-inorganic composite solar cells prepared in Example 1 and Comparative Examples 1 to 3 above.

From FIG. 4, it can be seen that, while the performance of Example 1 is maintained, the performance of Comparative Example 1 is rapidly decreased. That is, if the initial efficiency of Example 1 and Comparative Example 1 were similar, it can be confirmed that Example 1 is very excellent in terms of high temperature storage stability.

That is, it can be seen from Table 1 and FIG. 4 that the organic-inorganic composite solar cell according to an exemplary embodiment of the present specification has excellent performance and high-temperature storage stability.

10: first electrode
20: first common layer
30: light absorbing layer
40: second common layer
50: second electrode

Claims (11)

A first electrode;
A first common layer comprising a metal oxide containing tin provided on the first electrode;
A light absorbing layer comprising a compound of perovskite structure provided on the first common layer; And
An organic-inorganic composite solar cell comprising a second electrode comprising a carbon material provided on the light absorbing layer. The method according to claim 1,
The metal oxide containing tin is SnO ₂ , Sb: SnO ₂ , BaSnO ₃ And La: BaSnO _{3 The} organic-inorganic composite solar cell comprising at least one. The method according to claim 1,
The tin-containing metal oxide is an organic-inorganic composite solar cell that is included in the form of nanoparticles. The method according to claim 1,
The carbon material is carbon nanotube (CNT), graphite (graphite), graphene (graphene), graphene oxide (grapheme oxide), activated carbon, porous carbon (mesoporous carbon), carbon fiber (carbon fiber), conductive carbon black ( An organic-inorganic composite solar cell comprising one or more of carbon black) and carbon nano wire. The method according to claim 1,
The second electrode including the carbon material includes a first carbon material and a second carbon material different from each other,
The first carbon material includes one or more of carbon nanotube (CNT), graphite (graphite) and graphene (graphene),
The second carbon material is an organic-inorganic composite solar cell comprising a conductive carbon black. The method according to claim 5,
The content of the second carbon material is 30 to 60 parts by weight compared to 100 parts by weight of the first carbon material organic-inorganic composite solar cell. The method according to claim 5,
The second electrode comprising the carbon material is an organic-inorganic composite solar cell further comprising a binder. The method according to claim 7,
The content of the binder is 15 to 100 parts by weight compared to 100 parts by weight of the carbon material organic-inorganic composite solar cell. The method according to claim 1,
The light absorbing layer is an organic-inorganic composite solar cell further comprising a fluorine-based surfactant. The method according to claim 1,
An organic-inorganic composite solar cell comprising a second common layer between the light absorbing layer and the second electrode. The method according to claim 1,
The compound of the perovskite structure is an organic-inorganic composite solar cell represented by any one of the following Chemical Formulas 1 to 3:
[Formula 1]
R1M1X1 ₃
[Formula 2]
R2 _a R3 _(1-a) M2X2 _z X3 _(3-z)
[Formula 3]
R4 _b R5 _c R6 _d M3X4 _{z '} X5 _(3-z')
In Chemical Formulas 1 to 3,
R2 and R3 are different from each other,
R4, R5 and R6 are different from each other,
R1 to R6 are each independently C _n H _{2n + 1} NH ₃ ⁺ , NH ₄ ⁺ , HC (NH ₂ ) ₂ ⁺ , Cs ⁺ , Rb ⁺ , NF ₄ ⁺ , NCl ₄ ⁺ , PF ₄ ⁺ , PCl ₄ ⁺ , CH ₃ PH ₃ ⁺ , CH ₃ AsH ₃ ⁺ , CH ₃ SbH ₃ ⁺ , PH ₄ ⁺ , AsH ₄ ⁺ and SbH ₄ ⁺ is a monovalent cation selected from,
M1 to M3 are the same as or different from each other, and each independently Cu ^{2 +} , Ni ^{2 +} , Co ^{2 +} , Fe ^{2 +} , Mn ²⁺ , Cr ^{2 +} , Pd ^{2 +} , Cd ^{2 +} , Ge ^{2 +} , Sn ^{2 +} , Bi ^{2 +} , Pb ^{2 +} and a divalent metal ion selected from Yb ^{2 +} ,
X1 to X5 are the same as or different from each other, and each independently a halogen ion,
n is an integer from 1 to 9,
a is a real number of 0 <a <1,
b is a real number of 0 <b <1,
c is a real number in 0 <c <1,
d is a real number of 0 <d <1,
b + c + d is 1,
z is a real number of 0 <z <3,
z 'is a real number of 0 <z'<3.

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