BR102012030734A2 - PROCESS FOR PRODUCING MULTI-LAYER FINE MOVIES, MULTI-LAYLE FINE MOVIES, ORGANIC PHOTOELETROCHEMIC SOLAR CELLS AND USE OF ORGANIC PHOTOELECTRIC SOLAR CELLS - Google Patents

Abstract

PROCESS TO PRODUCE MULTILAYER THIN FILMS, MULTILAYER THIN FILMS, ORGANIC PHOTOELECTROCHEMICAL SOLAR CELLS AND USE OF ORGANIC PHOTOELECTROCHEMICAL SOLAR CELLS The present invention refers to a process for the production of thin layers that can be layered as layers of multilayered cells . It is still an object of the present invention to provide thin multilayer films that are produced by said process. In addition, the present invention relates to organic photoelectrochemical solar cells produced by the deposition of thin multilayer films produced by said process and to the use of organic photoelectrochemical solar cells.

Description

“PROCESS FOR PRODUCING MULTI-LAYER FILMS, MULTI-LAYER FILMS, ORGANIC PHOTOELECTRIC SOLAR CELLS AND USE OF ORGANIC PHOTOELECTRICAL SOLAR CELLS”.

FIELD OF INVENTION

The present invention relates to a process for the production of multilayer thin films by layer-by-layer deposition technique produced mainly from polyphenylene vinylene (PPV) and single wall carbon nanotubes (SWNT), which can be deposited as layers. active in solar cells for power generation. The present invention further relates to the multilayer thin films produced, the organic photoelectrochemical solar cells obtained from the deposition of said thin films and the use of solar cells in the generation of electric energy.

BACKGROUND OF THE INVENTION Research and development in the field of solar cells or

Photovoltaics have increased considerably due to the possibility of these devices providing clean, reliable and unlimited power, and the growing interest in this field only shows that energy is one of the biggest challenges facing humanity today and will face in the future.

2 0 Because pollution and global warming are phenomena

related to the burning of fossil fuels, it is essential to intensify the use of renewable energy sources so that in the long run there is no shortage of energy and no compromise of the environment. Therefore, renewable energy sources need to be further exploited on a global scale to meet future energy demand, which makes photovoltaic technology of growing interest.

Photovoltaic devices have the ability to generate electrical energy from semiconductors when they are illuminated by solar light and can generate energy anywhere there is light. This only reinforces the position of photovoltaic technology as one of the most promising renewable energy sources.

There are several types of solar cells used today, the most developed and produced being crystalline and multicrystalline silicon (Si) based solar cells which account for about 80-90% of the solar cell market. Conventional silicon solar cells require relatively large amounts of Si to efficiently absorb incident sunlight, as Si exhibits low absorption in the visible 15 and near infrared region. Thus, the need for large quantities of high purity Si is reflected in the high cost of solar cells produced from it.

Other commercially available solar cells are those based on inorganic thin films, such cells attempt to reduce the high costs of wafers in silicon solar cells through the use of semiconductor thin films that are generally deposited on a support substrate. Active layers have a thickness of the order of a few microns, but can absorb significant amounts of light due to the strong absorption in the materials.

The main materials used in the manufacture of thin film inorganic cells are amorphous silicon (a-Si), Cu (InGa) Se2 (CIGS) 1 and CdTe 5 which can achieve efficiencies of 10.1%, 19.4%, and 16.7%, respectively. But there are still barriers to the production of thin film-based solar cells, amorphous silicon purification, wafers production, cell processing, and encapsulation are all stages of the production process of these cells that are developed. 10 separately and then grouped together in the same thin film solar cell preparation plant, which results in a high cost.

Multi-layer organic photoelectrochemical solar cells are an alternative type of solar cell that has the advantages of low material cost, relatively simple fabrication, and different substrate types that can be used, including flexible substrates.

The published work Ariga, K et al. (Layer-by-layer assembly as a versatile bottom-up nanofabrication technique for exploratory research and realistic application, 2008) describes the potential 20 of layer-by-layer deposition (LbL) technique in the preparation of Multilayer thin films. Physicochemical aspects are reported and the application of carbon nanotubes in the preparation of LbL films, however, nothing indicates the application of these films in energy conversion as described in the present invention.

The work of collaborative Yu1 RXe (Fabrication of carbon based transparent conductive thin films using layer-by-layer technology, 2007) describes the preparation of transparent conductive thin films based on carboxylic groups functionalized single-wall carbon nanotubes (SWNT) ( -COOH) from the LbL technique. It represents an important innovation in the development of new electrodes, since most of those on the market are expensive. The ease of preparation of films (without sophisticated equipment) is highlighted as one of the main advantages of the developed approach. However, these films were prepared with PDDA and PSS1 insulating polymers and thus their application to the active layer of photoelectrochemical solar cells, as described in the present invention, is not feasible.

US20090314350 describes the preparation of organic solar cells by the so-called "nanoimpression" deposition method, which enables the deposition of films with nanometric patterns similar to the diffusion distance of the exciton, which considerably improve the efficiency of the devices, but not resembles the deposition LbL described in the present invention. CN101626063 describes the preparation of organic solar cells based on supramolecular systems composed of thiophene, phenylacetylene, biphenyl, aromatic amine, phthalocyanines as electron donor units and fullerene, perylene, carbon nanotubes and their 5 derivatives as units. electron receptors. The differential of this technology is related to the new supramolecular system and not to the deposition method of the active layer films, as described in the present invention.

The work of Guldi D. M. and colleagues (Layer-by-Layer Construction of Nanostructured Porphyrin-Fullerene Electrodes, 2002) describes the preparation of film-based electrodes containing a porphyrin-fullerene supramolecule deposited by the LbL method. In this supramolecule, the electron donor unit is porphyrin and the receptor is fullerene. The photoelectrochemical response of these electrodes was considerable, however, less intense than that obtained in the present invention. The authors do not report the use of 15 carbon nanotubes or conductive polymers to prepare these electrodes, making the present invention more efficient than described in this work.

BRIEF DESCRIPTION OF THE INVENTION

It is an object of the present invention to provide a process for producing multilayer thin films by layer-by-layer deposition technique that are deposited as active layers in solar cells comprising the following steps: a) substrate hydrophilization (optical glass) comprising the following phases:

a.1) Immersion of substrates in H2SCVHNO3 solution at a ratio of 7: 3 (by volume);

a.2) heating at 80 ° C for 1 hour;

a.3) washing substrates with deionized water; a.4) immersion of the substrates in NH4OH1 H2O2 and H2O solution (1: 1: 5 ratio (by volume); and

a.5) heating at 70 ° C for 1 hour.

b) preparation of polymer blocks by immersion of substrates

hydrophilized in 0.5 mg / ml aqueous solution of poly (xylylidenotetrahydrothiophene) (PTHT) for 1 minute followed by washing the substrates in deionized water and drying with gaseous N2.

c) deposition by immersion of the substrate on the PTHT precursor layer of an anionic sodium dodecylbenzene sulfonate layer

1 minute in their respective aqueous solution with a concentration equal to

3.48 mg / mL, followed by washing with deionized water and drying with N2, finalizing the bilayer deposition.

d) preparation of 100-layer poly (p-phenylene vinylene (PPV) / sodium dodecylbenzene sulfonate (DBS) bilayer films and deposition of 3, 5 and 8

bilayer carbon nanotube bilayers modified with anionic COOH and polyethylamine (PEI) groups by immersing the substrates in SWNT-COOH aqueous dispersion 0.6 mg / mL, followed by washing with deionized water and drying with N2.

e) soaking the substrates in PEI polycation aqueous solution, 1 mg / mL for 1 min, followed by washing in deionized water and drying

with gaseous N2.

f) conversion of PTHT to PPV by heating said films at 110 ° C for 1 hour in an inert N 2 atmosphere.

It is a further object of the present invention to provide the multilayer thin films which are produced by said process.

Still, an object of the invention is to provide solar cells

organic photoelectrochemicals based on said flexible multilayer thin films.

It is also an object of the invention to provide the use of thin film based organic photoelectrochemical solar cells in the generation of electrical energy.

BRIEF DESCRIPTION OF THE FIGURES

The structure and operation of the present invention, together with further advantages thereof may be better understood by reference to the accompanying drawings and the following descriptions:

20 Figure 1 shows optical absorption spectra in the UV-Vis region.

for movies (PPWDBS) no. The annex shows the maximum absorption variation at 400 nm as a function of the number of bilayers (PPWDBS) n. Figure 2 shows optical absorption spectra for (PPV / DBS) i2 and (PPV / DBS) 12: (PEI / SWNT-COOH) n (n = 2, 4 and 6) films. The annex shows the maximum absorption variation at 400 nm as a function of the number of bilayers (PEI / SWNT-COOH).

Figure 3 shows photoluminescence intensity spectra for

movies (PPV / DBS) no.

Figure 4 shows photoluminescence (PL) spectra for the (PPV / DBS) ioo and (PPV / DBS) 100 films: (PEI / SWNT-COOH) n, n = 3, 5 and 8.

Figure 5 shows epifluorescence images for (PPV / DBS) films: (PEI / SWNT-COOH) m, m = 3, 5 and 8.

Figure 6a shows AFM images for the movie (PPV / DBS) ioo

Figure 6b shows AFM images for the movie (PPV / DBS) ioo in its 3D projection.

Figure 7a shows AFM images for film (PPV / DBS) i00: (PEI / SWNT) 3.

Figure 7b shows AFM images for the film (PPV / DBS) ioo: (PEI / SWNT) 3 in its 3D projection.

Figure 8a shows AFM images for film (PPV / DBS) i00: (PEI / SWNT) 5.

Figure 8b shows AFM images for the movie.

(PPV / DBS) i00: (PEI / SWNT) 5 in its 3D projection.

Figure 9a shows AFM images for film (PPV / DBS) i00: (PEI / SWNT) 8. Figure 9b shows AFM images for the film (PPV / DBS) ioo: (PEI / SWNT) 8 in its 3D projection.

Figure 10 shows photochronometric measurements for multilayer (PPV / DBS) 100 and (PPV / DBS) 100: (PEI / SWNT) 8 films.

Figure 11 shows photochronamperometric measurements for

multilayer (PPV / DBS) 100 and (PPV / DBS) 10th: (PEI / SWNT) n) n = 3, 5 and 8.

Figure 12 shows the PEDOT energy diagram: PSS, PPV, semiconductor (s-SWNT) and metallic (m-SWNT) carbon nanotubes.

Figure 13 shows photochronometric measurements for multilayer films (PPV / DBS) ioo: (PEI / SWNT-COOH) n, n = 5 and 8, with and without hole carrier layer (PEDOT: PSS).

DETAILED DESCRIPTION OF THE INVENTION

While the present invention may be susceptible to different embodiments, preferred embodiments are shown in the drawings and in the following detailed discussion with the understanding that the present disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the present invention to what has been described. illustrated and described here.

The main approach of this invention relates to a process for producing multilayer thin films produced by the layer-by-layer deposition technique using mainly polyphenylene vinylene (PPV) and single wall carbon nanotubes (SWNT).

It is a further object of the present invention to provide multilayer thin films which are produced by said process. The present invention further relates to organic photoelectrochemical solar cells produced by the deposition of the multilayer thin films produced by the process defined herein.

Furthermore, the present invention relates to the use of organic photoelectrochemical solar cells in the generation of electric energy.

The main materials used in the preparation of thin films were carboxyl groups functionalized single-wall carbon nanotubes - SWNT-COOH, poly (3,4-ethylenedioxythiophene)

poly (styrenesulfonate) - PEDOT: PSS (1.3 wt.% aqueous solution), polyethylenimine - PEI, poly (xylylidenetetrahydrothiophene) - PTHT (aqueous solution)

0.25 mass%). The structures of these materials are illustrated below:

PEBOT PEl: FSS

In a preferred embodiment, the process for producing multilayer thin films by the cationic and anionic polyelectrolyte layer-by-layer deposition technique comprises the following steps: a) substrate hydrophilization (optical glass) comprising the following steps:

a.1) immersion of the substrates in H2SO4 solution in a 7: 3 ratio (by volume);

a.2) heating at 80 ° C for 1 hour;

a.3) washing substrates with deionized water; a.4) immersion of the substrates in NH4OH, H2O2 and H2O solution (1: 1: 5 ratio (by volume)), and

a.5) heating at 70 ° C for 1 hour.

b) preparation of polymer blocks by immersion of substrates

hydrophilized in 0.5 mg / ml aqueous solution of poly (xylylidenotetrahydrothiophene) (PTHT) for 1 minute followed by washing the substrates in deionized water and drying with gaseous N2.

c) deposition by immersion of the substrate on the PTHT precursor layer of an anionic sodium dodecylbenzene sulfonate layer

1 minute in their respective aqueous solution with a concentration equal to

3.48 mg / mL, followed by washing with deionized water and drying with N2, finalizing the bilayer deposition.

d) preparation of 100-layer poly (p-phenylene vinylene 20 (PPV) / sodium dodecylbenzene sulfonate (DBS) bilayer films and deposition of 3, 5 and 8

Single-wall carbon nanotube bilayers modified with COOH and polyethylamine (PEI) anionic groups by immersing the substrates in 0.6 mg / mL SWNT-COOH aqueous dispersion, followed by washing with deionized water and drying with N2.

e) soaking the substrates in PEI polycation aqueous solution, 1 mg / mL for 1 min, followed by washing in deionized water and drying

with gaseous N2.

f) conversion of PTHT to PPV by heating said films at 110 ° C for 1 hour in an inert N2 atmosphere As shown below:

on substrate covered with an insoluble thin film of poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) (PEDOT: PPS). This film was deposited by the spin-coating method (2800 rpm) from an aqueous polymer solution containing 0.25 mass% ethylene glycol (EG) and heated for 12 hours at 70 ° C in ambient atmosphere, followed by Heat in a vacuum oven for 1 hour at 140 ° C to remove excess water and EG from the film. After this procedure, a water-insoluble PEDOT.PSS film was obtained, on which the films were deposited. Thus, another film architecture was obtained which was characterized only photoelectrochemically. The architecture in question is: 20 (PEDOT: PSS) :( PPV / DBS) ioo: (SWNT-COOH / PEI) n, n = 3, 5 and 8.

PTHT

PPV

In an alternative embodiment thin films are also prepared.

EXAMPLES Example 1 - MOVIE GROWTH STUDY

Figure 1 shows the absorption spectra behavior of PPV / DBS multilayer films. The absorption broadband in the range 350-500 nm is attributed to π- π * transitions between the delocalized states 5 coupled with the vibronic states, and is characterizing the effective conversion of the unconjugated PTHT precursor to PPV.

The annex of figure 1 shows that the maximum intensity (400 nm) of the transition increased linearly as the number of layers deposited increased, indicating that after each step, the same amount of material was deposited on the substrate, suggesting a control. of precise thickness. The deposition of PEI / SWNT-COOH bilayers on the (PPV / DBS) i2 block also showed a linear behavior (Figure 2), suggesting that similar amounts of carbon and PEI nanotubes were deposited. In this case, linearity enables the deposition of thin films 15 with accurate interfacial control between materials with low ionization potential (electron donors) (PPV) and high electronic affinity (electron receivers), which is a parameter that is directly related. the efficiency of electronic devices such as organic photoelectrochemical solar cells.

2 0 The growth of multilayer films (PPV / DBS) was also

monitored by photoluminescence spectroscopy (figure 3), and based on emission intensity, growth is linear up to at least 15 bilayers. This result is in agreement with that observed in absorption spectroscopy (Figure 1).

All emission spectra of PPV / DBS films showed the maximums in the same position a well-resolved vibrational structure with a 0-0 phonon band at 492 nm. The gradual increase of photoluminescence intensity (PL) of the films (PPV / DBS) with the increase of the number of bilayers is related to the increase of the luminescent material concentration. The well-resolved vibronic structure and the nearly constant vibrational intensity ratio presented in all spectra 10 suggest that the PPV chains are emitting as isolated species and are not undergoing energy transfer processes or forming excimer or exciplex species. Also, due to the high intensity of 0-0 band, internal filter effect is virtually absent in these movies.

From these results, began the preparation and characterization of 15 films with higher number of layers, ie films with higher thickness values. The application of thicker films is directly related to the need to increase light absorption, which is a determining parameter for the efficiency of photovoltaic and photoelectrochemical devices.

2 0 Example 2 - PHOTOLUMINESCENCE OF MOVIES (PPV / DBS) i00: (PEI / SWNT-COOH) n

Photoluminescence spectroscopy may also provide direct evidence of the interaction between the PPV polymer and carbon nanotubes. The photoluminescence spectra shown in Figure 4 correspond to films with the following architectures: (PPV / DBS) 10 and [(PPV / DBS) 10: (PEI / SWNTCOOH) n], where n = 3, 5 and 8. Note- As the number of SWNT-containing bilayers increased, photoluminescence (PL) decreased dramatically.

5 This suggests an appreciable suppression of photogenerated exons in the polymer. Decreases of up to 60% of photoluminescence (PL) have been verified, which can be attributed to the reduction in the population of the singlet excitons in the PPV before radioactive recombination due to the presence of a pronounced electro-affinity material such as carbon nanotubes 10. . Electron transfer is a short distance process, so there is a high probability that this is the most efficient process at the interface (heterojunction) between (PPV / DBS) ioo and the (PEI / SWNT-COOH) n blocks responsible for suppression. photoluminescence (PL).

Example 3 - EPIFLUORESCENCE MICROSCOPY The morphology of multilayer films was analyzed from the

(PPV / DBS) ioo and [(PPV / DBS) i0o: (PEI / SWCNT) n], where n = 3, 5 and 8. Figure 5 shows epifluorescence micrographs for the films based on the mentioned architectures. previously.

The film containing only PPV layers (Figure 5) showed a homogeneous yellow 20 glow from the emission of this polymer. After deposition of

3 layers (PEI / SWNT) over the block (PPV / DBS), a decrease in film emission was observed. This decrease in photoluminescence (PL) was also homogeneous, as can be seen in Figure 7, indicating a homogeneous deposition of carbon nanotubes on the PPV block. With the subsequent deposition of 5 and 8 layers of (PEI / SWCNT), that is, increasing the concentration of carbon nanotubes, a more pronounced decrease in photoluminescence intensity (PL) was observed. These 5 results are in agreement with the photoluminescence (PL) spectra shown in Figure 4. The decrease in emission is represented by the dark domains that appear clearly in the epifluorescence images (Figure 5), and correspond to the presence of carbon nanotubes on the surface. PPV / DBS block.

IO Example 4 - ATOMIC FORCE MICROSCOPY (AFM)

The uniformity of the deposition process and the morphology of multilayer films were also investigated by atomic force microscopy (AFM). The images were obtained in non-contact mode and the evaluated areas were 5.0 x 5.0 μηη2.

Figure 6a shows the AFM image for the (PPV / DBS) ioo movie.

in which almost all the substrate surface (ITO) was covered. However, the high average roughness value (41.27 nm) and the three-dimensional surface projection shown in Figure 6b suggest the formation of a nonuniform deposition. This indicates that after a certain number of

20 bilayers, it is difficult to obtain uniform monolayers of the PPV and DBS molecules.

After adding 3 and 5 bilayers (PEI / SWNT) to the bilayers (PPV / DBS), a distinct change in morphology can be noted for both films. It was observed that clumps begin to appear on the (PPV / DBS) film after the addition of 3 layers (PEI / SWNT), as illustrated in Figure 7a. It was also observed that the average roughness (41.83 nm) did not change significantly.

5 When 5 bilayers (PEI / SWNT) were deposited, a higher

The increase in the density of the agglomerates and their good dispersion were verified (Figure 8a and 8b), with the average roughness of 42.03 nm very close to the values mentioned above for the (PPV / DBS) i0oe (PPV / DBS) 10o films: (PEI / SWNT) 3. With the 8-layer deposition, small 10 carbon nanotube clusters were visualized soaked with PEI polymer, as can be seen in Figure 9a. The average roughness of this film was 19.25 nm, much lower than that observed for previous films. This indicates that the 8 layers of (PEI / SWNT) promoted a more efficient coating of the PPV / DBS film surface, which is also shown in Figure 9b.

Example 5 - PHOTOELECTCHEMICAL MEASURES

The photoelectrochemical performance of PPV-based multilayer films with SWNT-COOH was evaluated by photocurrent measurements as a function of time (photochronamperometry) in a 20-compartment photoelectrochemical cell using the films as photoelectrodes. The electrolyte used was a 0.5 mol L1 solution of KCI in deionized water saturated with

O2, which acted as a redox mediator. The film containing only PPV layers showed reduced photoactivity, ie very low photocurrent, which is possibly related to limited excitonic dissociation in this low dielectric constant polymer (Figure 10).

For PPV film containing carbon nanotubes as photoelectrode, appreciable photocurrent values immediately appeared under illumination 5 and dropped instantly when it was stopped. This indicates that nanotubes may be acting as dissociation centers for the PPV-generated ecitons, increasing the number of charge carriers that reach the electrolyte interface.

The photoelectrochemical response has been repeated several times, however, a decrease in photocurrent over time is an indication that some kind of degradation or dissolution of the active layer of the photoelectrode is occurring. From figure 11, it was noted that the photocurrent values increased with the increase in the number of carbon nanotube bilayers, a fact related to the increase in electron-hole pair separation.

Photocurrent generation possibly corresponds to transfer

photogenerated electrons from PPV to carbon nanotube, a fact already suggested by the photoluminescence spectroscopy presented above.

Analyzing photocurrent generation in a photoelectrochemical cell is almost always a complex problem, as competing contributions of 20 charge transport in the film and charge injection towards the electrodes and / or toward the electrolyte may occur. Consequently, the relative position of the materials HOMO and LUMO energy levels, morphology and the nature of the film surface in contact with the electrolyte solution certainly play an important role.

For PPV multilayer films containing carbon nanotube layers, we can assume that the polymer / carbon nanotube 5 interfaces can allow photogenerated electrons or holes to be easily transferred from PPV to carbon nanotubes, effectively competing with each other. deactivation processes in the conductive polymer, thus optimizing the charge transfer.

For the multilayer films of the present invention, while PPV phase 10 is almost entirely continuous throughout the film (Figures 9a and 9b), only a fraction of nanotubes is supposed to be in contact with the polymer. With this it can be said that the polymer phase offers a greater number of possible paths for cargo transportation (holes). In turn, the carbon nanotube phase, made up of a few layers of agglomerated tubes, will have a less efficient charge transport (electrons). This suggests that photocurrent values may therefore be limited by electron transport, not just holes. In this sense, the morphology and dispersion level of nanotubes can play a relevant role on the total charge transport in the film.

2 0 The cathodic photocurrent observed for all multilayer films

based on PPV and SWNT indicates that electron flow occurs toward the electrolyte, where the redox mediator (02/02) is responsible for transporting the electrons to the platinum counter electrode (Figure 12). The photocurrent values in photoelectrochemical cells can be increased by introducing a hole injecting layer between the active layer and the ITO electrode, which generally increases the efficiency of hole transport.

5 Figure 13 shows the photoelectrochemical responses of

multilayer films with and without PEDOT: PSS layers. Clearly, cells containing PEDOT: PSS showed higher and more stable photocurrent values, suggesting the direct influence of this material on the charge transfer process between PPV and carbon nanotube through a more efficient PEDOT hole collection. .

Thus, while only a few embodiments of the present invention have been shown, it will be appreciated that various omissions, substitutions and changes may be made by one of ordinary skill in the art without departing from the spirit and scope of the present invention. The embodiments described herein should be considered in all respects only as illustrative and not restrictive.

It is expressly provided that all combinations of elements that perform the same function in substantially the same way to achieve the same results are within the scope of the invention. 20 Substitutions of elements of one embodiment described for another are also fully intended and contemplated.

One must also understand that the drawings are not necessarily to scale, but that they are only of a conceptual nature. The intent is therefore to be limited as indicated by the scope of the appended claims.

Claims (7)

1. Process for the production of multilayer thin films for deposition in organic photoelectrochemical solar cells characterized by the fact that it comprises the following steps: a) substrate hydrophilization (optical glass) comprising the following steps: a.1) immersion of substrates in 7: 3 H2SO4 solution (by volume); a.2) heating at 80 ° C for 1 hour; a.3) washing substrates with deionized water; a.4) immersion of the substrates in NH4OH, H2O2 and H2O solution (1: 1: 5 ratio (by volume); and a.5) heating at 70 ° C for 1 hour. b) preparing the polymer blocks by soaking the hydrophilized substrates in 0.5 mg / ml aqueous solution of poly (xylylidenetetrahydrothiophene) chloride (PTHT) for 1 minute followed by washing the substrates in deionized water and drying with gaseous N2. c) deposition by immersion of the substrate on the PTHT precursor layer of a layer of the anionic electrolyte sodium dodecylbenzene sulfonate for 1 minute in its respective aqueous solution at a concentration of 3.48 mg / mL, followed by washing with deionized water and drying with N2, ending the deposition of a bilayer. d) preparation of 100-layer poly (p-phenylene vinylene (PPV) / sodium dodecylbenzene sulfonate (DBS) bilayer films and deposition of 3, 5 and 8 single-wall carbon nanotube bilayer modified with COOH and polyethylamine (PEI) anionic groups ), by immersing the substrates in SWNT-COOH 0.6 mg / mL aqueous dispersion, followed by washing with deionized water and drying with N2. e) immersing the substrates in aqueous PEI polycation solution, 1 mg / mL for 1 min followed by washing in deionized water and drying with gaseous N2. f) conversion of PTHT to PPV by heating said films at 110 ° C for 1 hour in an inert N 2 atmosphere. Process for the production of multilayer thin films for deposition in organic photoelectrochemical solar cells according to claim 1, characterized in that said multilayer thin films are prepared by deposition of polymer layers and nanotube layers. carbon. Process for producing multilayer thin films for deposition in organic photoelectrochemical solar cells according to claim 1, characterized in that the nanotubes are single-walled carbon nanotubes functionalized with anionic COOH groups in deionized water . Multilayer thin films produced by the process as defined in claims 1 to 3, characterized in that the films are preferably composed of PPV polymer (obtained after conversion of PTHT) and single wall carbon nanotubes SWNT-COOH. Organic photoelectrochemical solar cell characterized by the fact that it is produced by the deposition of the multilayer thin films produced by the process as defined in claims 1 to 3. Organic photoelectrochemical solar cell according to claim 5, characterized in that it is flexible. Use of the organic photoelectrochemical solar cell as defined in claims 6 and 7, characterized in that it is in the generation of electric energy.