Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.

Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.Tóm tắt tiếng anh:Nghiên cứu chế tạo và khảo sát đặc trưng của vật liệu perovskite vô cơ – hữu cơ ứng dụng cho linh kiện pin mặt trời lai.

MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY GRADATE UNIVERSITY OF SCIENCE AND TECHNOLOGY  THACH THI DAO LIEN RESEARCH ON SYNTHESIS AND CHARACTERIZATION OF INORGANIC- ORGANIC PEROVSKITE MATERIALS FOR HYBRID SOLAR CELLS APPLICATION Major: Materials for Electronics Code : 9440123 SUMMARY OF DOCTOR THESIS HANOI - 2022 The thesis was completed at Institute of Materials Science, Vietnam Academy of Science and Technology Supervisors: Assoc.Prof PhD Pham Van Hoi PhD Le Ha Chi Reviewer 1: Reviewer 2: Reviewer 3: The dissertation defended at Graduate University of Science and Technology, 18 Hoang Quoc Viet street, Hanoi Time:………………………………… The thesis could be found at: - National Library of Vietnam - Library of Graduate University of Science and Technology List of publication related to this thesis [1] Le Ha Chi, Pham Duy Long, Hoang Vu Chung, Do Thi Phuong, Do Xuan Mai, Nguyen Thi Tu Oanh, Thach Thi Dao Lien, Le Van Trung, “Galvanic-cell-based synthesis and photovoltaic performance of ZnO- CdS core-shell nanorod arrays for quantum dots sensitized solar cells”, Applied Mechanics and Materials, Vol 618, pp 64-68, 2014 [2] Le Van Trung, Tran Quoc Dat, Hoang Hong Ly, Thach Thi Dao Lien, Do Xuan Mai, Do Thi Phuong, Hoang Vu Chung, Pham Duy Long, Pham Van Hoi, Le Ha Chi, “Synthesis and photoelectrochemical properties of the ZnO/CdS core-shell nanorod arrays”, Advances in Optics, Photonic, Spectroscopy & Applications VIII, pp.810-814, 2015 [3] Thach Thi Dao Lien, Nguyen Tien Dai, Nguyen Tien Thanh, Pham Van Phuc, Nguyen Thi Tu Oanh, Pham Duy Long, Pham Van Hoi, Le Ha Chi, “Tin fluoride assisted growth of air stable perovskite derivative Cs2SnI6 thin film as a hole transport layer”, Materials Research Express, Vol.6, 116442, 2019 [4] Thach Thi Dao Lien, Pham Van Phuc, Nguyen Thi Tu Oanh, Nguyen Si Hieu, Ta Ngoc Bach, Pham Duy Long, Pham Van Hoi, Le Ha Chi, “Using solvent vapor annealing for the enhancement of the stability and efficiency of monolithic hole-conductor-free Perovskite solar cells”, Communications in Physics, Vol 30, No 2, 133-141, 2020 4 INTRODUCTION  The thesis necessity Global energy demand has continued to increase steadily over the past decades The International Energy Agency (IEA) estimates that, in 2019, total primary energy consumption was 583.9 EJ In which, the structure of global primary energy consumption in 2019 by energy resource of various types such as: oil (33.1%), natural gas (24.2%), coal (27.0%), nuclear (4.3%), hydropower (6.4%) and renewable energy (5.0%) Thus, the order of density of the fuels remains unchanged, the top is still oil, the second is coal and the third is natural gas, these three fuels account for the absolute highest proportion, totaling up to 84.3% Renewable energy had a faster growth rate during this period The demand for nuclear energy has decreased, partly due to the nuclear disaster (Three Mile Island incident in 1979, Chernobyl in 1986 and Fukushima in 2011), so countries did not continue to develop this type of energy However, the traditional fossil fuel sources such as coal, oil, gas are limited in quantity and are gradually exhausted, unable to meet the increasing energy demand of people Furthermore, the burning of fossil fuels generates more than 21 billion tons of CO2 per year That contributes to global warming and causes serious environmental pollution Therefore, we must look for abundant, clean, cheap and safe alternative energy sources Among the new energy sources such as biomass energy, wind, water, etc., there is no energy source that can meet human needs with unlimited energy from the sun Every year, the sun brings to the earth an extremely abundant energy of 23,000 TW Solar energy is a green and clean energy source, reducing environmental pollution, can be deployed and installed anywhere there is sunshine, proactive in power supply for buildings Realizing the benefits from using solar energy, the Prime Minister also issued Decision No 13/2020/QDTTg to encourage the development of solar power in Vietnam from May 22, 2020 But so far, solar energy has not been exploited effectively because existing solar cell technologies are still quite expensive compared to fossil energy, the use of electricity from renewable energy sources has been still entitled to an electricity purchase price and supporting policies In an effort to research and develop a new generation of solar cells that are cheaper and easier to manufacture, the discovery of inorganic-organic perovskite materials shows that this family of materials exhibits mysterious properties for photovoltaic absorbers [1][2] The organic—inorganic hybrid halide perovskites have strong optical absorption in the visible region [3], high carrier mobility [4], an adjustable spectral absorption range [5], long diffusion lengths [6], and the simplicity and affordability of fabrication [7] [8] Although much has been learned from the recent research efforts, exciting work in developing new hybrid perovskites and a number of questions in understanding these materials still remains In addition, largescale deployment of perovskite solar cells will depend on whether stability and toxicity of the lead (Pb) component issues can be solved [9] While the research on inorganic-organic perovskite materials is currently very active in the world, the research and application of this material in Vietnam is still very limited Therefore, we chose the thesis topic: "Research on synthesis and characterization of inorganic - organic perovskite materials for hybrid solar cells application" to research and evaluate the photovoltaic properties of the inorganic-organic perovskite materials to apply for hybrid solar cells in Vietnam  Objectives of the study Research to control electron transport layers and hybrid organicinorganic perovskite materials by changing the composition of organic and inorganic components as a light absorber for highly efficient solar cells Design and fabricate prototype hybrid perovskite solar cells  Main research contents of the thesis - Research on synthesis and characterization of inorganic-organic perovskite materials such as CH3NH3PbI3, multi-component perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3, hybrid 2D/3D Perovskite, Pb-free double perovskite Cs2SnI6 - Fabricating thin films of nanostructured semiconductor TiO2 and ZnO with different morphological structures such as compact or mesoporous nanoparticles, nanorods as electron transport layers - Research on fabrication and characterization of perovskite solar cells with different structures such as planar PSCs, mesoporous PSCs, holetransport-layer free perovskite solar cells using the Solar Simulator  Research method The research method used in the thesis is the experimental method The morphology, crystalline structure and properties of the materials were studied by scanning electron microscope (SEM), X-ray diffraction, X-ray energy-dispersive spectroscopy, UV-VIS absorption, , The characteristics of solar cells were investigated by measuring J-V characteristics under Solar Simulator illumination Most of the experiments are mainly carried out at the Institute of Materials Science, Vietnam Academy of Science and Technology  Thesis structure This thesis consists of 137 pages, 10 tables, 90 figures and 125 references including these main parts: introduction, three chapters in content and conclusion The main results were published on scientific articles: 02 articles were published on international journals; 02 articles were published on national journals  New contributions of the thesis: - Inorganic - organic perovskite materials such as CH3NH3PbI3, multicomponent perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3, hybrid 2D/3D Perovskite, Pb-free double perovskite Cs2SnI6 have been successfully synthesized which exhibited strong absorption properties and suitable bandgaps - Thin films of nanostructured semiconductor TiO2 and ZnO (compact or mesoporous nanoparticles, nanorods) have been successfully grown on conductive FTO/glass substrates as electron transport layers Au nanoparticles have been fabricated by thermal evaporation to study plasmonic effects such as better light traps and charge separation of the photo-generated carriers for improving the performance of perovskite solar cells - The processes of manufacturing planar PSCs, mesoporous PSCs and hole-transport-layer free perovskite solar cells have been studied The obtained results showed that the isopropyl alcohol (IPA) solvent vapor annealing treatment strongly influenced on the growth of perovskite materials on triple mesoscopic layers thus improved stability and efficiency of hole-transport-layer free perovskite solar cells to 7,69% CHAPTER LITERATURE REVIEW Chapter is presented in 35 pages, in which a general introduction about the solar cell generations, the typical parameters of solar cells In particular, Hybrid inorganic–organic perovskites have emerged as a promising class of materials for optoelectronic applications Therefore, this thesis focuses on researching and developing perovskite solar cells with low cost and simple manufacturing technology The crystal structure of perovskite materials, classification of perovskite material families, the properties of perovskite materials are strictly related to the crystal structure properties The organic-inorganic hybrid halide perovskites exhibit high carrier mobility, an adjustable spectral absorption range, long diffusion lengths, and the simplicity and affordability of fabrication Its properties are highly dependent on several key factors of processing techniques such as deposition method, environment, humidity, precursor composition and solvents and additives used Common types of perovskite solar cell construction and classification of materials used in perovskite solar cells have been mentioned The operating principle in perovskite solar cells and influencing factors such as defects, recombination at the interface, and durability have also been investigated At the same time, further investigation of the fabrication and properties of the organic-inorganic hybrid perovskite materials allows to improve understanding of this group of materials From there, it is possible to get the desired properties, improve the performance and stability of perovskite solar cells CHAPTER EXPERIMENTAL Chapter is presented in 26 pages including: 2.1 Chemicals, laboratory instruments 2.2 Synthesis of electron transport layers (ETL) Research and fabricate electron transport layers such as TiO and ZnO with different morphological structures such as such as compact or mesoporous nanoparticles, and nanorods 2.3 Synthesis of inorganic-organic perovskite materials - Synthesized inorganic - organic perovskite materials such as CH3NH3PbI3, MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3, hybrid 2D/3D Perovskite, Pbfree double perovskite Cs2SnI6 2.4 Characterisation Techniques - Techniques for characterization are approached from the modern method: SEM, XRD, EDX, UV-Vis, PL, J-V CHAPTER CHARACTERIZATION OF ORGANIC - INORGANIC PEROVSKITE MATERIALS, TiO2 AND ZnO NANO MATERIALS USED IN SOLAR CELLS Chapter is presented in 30 pages including: 3.1 Nanostructured electron transport layers 3.1.1 TiO2 compact thin films prepared by sputtering and annealing Figure 3.1 FE-SEM images of surface (a) and cross-section (b) of TiO2 film samples were prepared by sputtering and annealing at 450oC Figure 3.1 is the FE-SEM image of the TiO2 film sample which has been fabricated by sputtering and annealing at 450oC The results show that the obtained TiO2 film has a tightly packed nanoparticle structure with a particle size of about 10÷20 nm, good adhesion on the substrate surface, suitable for making TiO2 compact thin films as a blocking layer for electron selective contacts The controllable TiO film thickness corresponds to the thickness of the initially sputtered Ti metal film according to the sputtering power and time 3.1.2 TiO2 mesoporous thin films prepared by spin-coating The mesoporous TiO2 thin film (mp-TiO2) samples were fabricated by spin-coating the precursor solution diluted from TiO paste From the SEM image in Figure 3.2, it is shown that we can adjust the thickness of the thin film from 100 to 1800 nm by diluting TiO2 paste with ethanol or changing the number of the spin-coating layers Specifically, the T600/SC TiO paste with a concentration of 7% was diluted with ethanol at the ratios of 1:1, 1:2 and 1:4 to form mp-TiO layers with the different thicknesses (600 nm, 300 nm and 100 nm) When increasing the times of spin-coating layers, we get a corresponding thickness of ~ 1800 nm (see Figure 3.2) Figure 3.2 FE-SEM images of TiO2 film samples were prepared by spin-coating with different thicknesses 3.1.3 TiO2 compact and mesoporous thin films prepared by screenprinting Figure 3.3 FE-SEM images of TiO2 compact and mesoporous thin films prepared by screen-printing with the low and high magnifications The FE-SEM images in Figure 3.3 show cross-sectional images with different magnifications of TiO2 compact and mesoporous thin films (blTiO2/mp-TiO2) fabricated by screen-printing method FE-SEM images show that the bl-TiO2 layer has a thickness of 50 nm, while the mp-TiO layer has a thickness of 600 nm The thickness of the mesoporous film (mp-TiO2) can be adjusted by diluting the TiO paste with ethanol or varying the number of the screen-printing layers 3.1.4 Nano composite TiO2-Au thin film To study the plasmonic effect of Au nanoparticles on TiO2 thin films, gold metal has been thermally evaporated and then annealed at 400 oC Samples with gold metal thicknesses of nm, nm and 10 nm (determined by a quartz oscillator) were labelled corresponding to M1, M2 and M3 Sample M0 is a blanked sample, meaning TiO film is not coated with gold FE-SEM images in Figure 3.4 show that the gold particles are well-distributed over the entire film surface, when the gold metal thickness increased, the size of Au nanoparticles also increased Figure 3.4 FE-SEM images of TiO2 compact films combined with gold nanoparticles with different thicknesses prepared by thermal evaporation 3.1.5 ZnO nanorod film Figure 3.6 (a) Top-view and (b) Cross-sectional FESEM images of ZnO nanorod arrays synthesized on FTO/glass substrates using a Galvanic-cell-based method in 25 mM Zn(NO3)2 and 25 mM HMTA solution at 70oC for hour The FE-SEM images in Figure 3.6 show that well-aligned ZnO nanorods synthesized by a Galvanic-cell-based method in 25 mM Zn(NO3)2 and 25 mM HMTA solution at 70oC for hour are directly grown on the FTO substrate without the seed layer The average length of ZnO nanorods is about µm 3.2 Research and fabrication results of Perovskite materials 3.2.1 Perovskite CH3NH3PbI3 The factors affecting the process of film formation that we have investigated are: 3.2.1.1 Effect of coating techniques Figure 3.8 FE-SEM images of CH3NH3PbI3 perovskite films prepared by different techniques: (a) spin-coating technique, (b) spin-coating technique with anti-solvent treatment and (c) spray-coating technique Figure 3.8 shows the results of morphological investigation of CH3NH3PbI3 perovskite films fabricated by one-step solution method using different techniques: (a) spin-coating technique, (b) spin-coating technique with anti-solvent treatment and (c) spray-coating technique From the FESEM images, it can be seen that the film fabricated by spin-coating technique with anti-solvent treatment has the best uniformity and surface coverage The anti-solvent with low boiling point and poor miscibility with precursor solution solvent will significantly affect the rapid crystallization of the perovskite material and flatten the surface of the perovskite film more than conventional spin-coating techniques Figure 3.12 Top-view FE-SEM images of mesoscopic CH3NH3PbI3/ZnO nanorod fabricated by one-step solution method (a) and two-step solution method (b) Figure 3.12 presents the FE-SEM images of the surface morphology of the CH3NH3PbI3 perovskite films coated on the ZnO nanorods Thus, we can see that the one-step method is suitable for coating the CH 3NH3PbI3 perovskite film on top of the planar structures In the case of ZnO nanorods, the two-step solution method is more suitable than the one-step solution method to coat the CH3NH3PbI3 perovskite film on top of mesoscopic layer 3.2.1.2 Effect of precursor concentration Figure 3.13 FE-SEM image of perovskite CH3NH3PbI3 film changes with precursor concentration from M; 1.1 M; 1.2M to 1.3 M In the one-step coating method, the mixture of two precursors PbI and CH3NH3I (abbreviated as MAI) with the concentration investigated varies from M; 1.1 M; 1.2 M to 1.3 M is dissolved in a mixture of two types of solvents N,N-dimethylformamide (DMF) and Dimethyl sulfoxide (DMSO) with a ratio of 4:1 in volume The film coating method used the spincoating technique with anti-solvent as described above, then samples were annealed at 100oC for hour to form perovskite film The results of morphological investigation by FE-SEM images in Figure 3.13 show that perovskite films with precursor concentration from M to 1.2 M obtained better surface coverage When the precursor concentration increased to 1.3 M, there was an unfavorable film morphology 3.2.1.3 Effect of annealing temperature Figure 3.14 FE-SEM images of CH3NH3PbI3 perovskite films annealed at different temperatures, from 80°C, 100°C, 120°C to 150°C for h Thermal annealing is an essential step to initiate or accelerate the reaction between the organic CH 3NH3I (abbreviated as MAI) and inorganic PbI2 species to form the perovskite CH 3NH3PbI3 film In this experiment, perovskite CH3NH3PbI3 films were deposited from a precursor solution of 1.1 M concentration onto glass/FTO substrates by spin-coating method with anti-solvent treatment at different annealing temperatures from 80°C to 150°C for hour using the Torrey Pines EchoTherm HS40 hotplate FESEM images (in Figure 3.14) show that the film annealed at 80°C has the unfavorable film The films annealed at 100°C and 120°C resulted in better surface coverage and uniform films But film annealed at 150°C will show unevenness because the high temperature affects the kinetics of solvent evaporation and perovskite crystallization 3.2.2 Multi-component Perovskite material Figure 3.15 FE-SEM image and figure 3.16 XRD pattern of MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 Figure 3.15 presents the FE-SEM image of the multi-component mixed MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 perovskite film fabricated by the one-step coating with anti-solvent treatment as described above The XRD patterns compare the perovskite CH3NH3PbI3 (Figure 3.16 a) and mixed perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 (Figure 3.16 b) at the same fabrication conditions This suggests that perovskite film formation occurs in both samples However, as shown in the figure, we still see the appearance of the peak of impurity PbI2, at the angle of theta = 12.8 o The intensity of the characteristic perovskite peaks in the mixed multi-component perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 is stronger while the impurity PbI2 peak is smaller than that in the CH3NH3PbI3 perovskite 3.2.3 2D/3D Perovskite Surface FE-SEM images (Figures 3.17 and 3.18) and XRD diagrams (Figure 3.19) of 2D/3D hybrid perovskite films (5-AVA)x(MA)1-xPbI3 annealed by conventionally annealing treatment (TA) and solvent annealing treatment in isopropanol (SA) showed that the use of isopropanol solvent annealing treatment (IPA solvent annealing) supported the better crystallization of perovskite material on porous structures Figures 3.17 and 3.18 FE-SEM images and Figure 3.19 XRD patterns of 2D/3D hybrid perovskite films (5-AVA)x(MA)1-xPbI3 annealed by conventionally annealing treatment (TA) and isopropanol solvent annealing treatment (SA) 3.2.4 Pb-free double perovskite Cs2SnI6 Figure 3.20 FE-SEM images and Figure 3.21 XRD patterns of Cs2SnI6 film with SnF2 addition 0% (M1), 5% (M2), 10% (M3) and 20% (M4) FE-SEM images and X-ray diffraction patterns in Figure 3.20 and Figure 3.21 indicated the effect of additive composition SnF on the morphology and structure of Cs2SnI6 films In addition to the characteristic diffraction peaks of Cs2SnI6, we also observed that CsI(110) and CsI(200) impurity peaks appeared at 2θ = 27.6° and 39.4° The results show that SnF2 addition supported the Cs2SnI6 crystal formation and significantly reduced the impurity peaks CsI(200), especially in sample M3 with 10% of additive SnF2 3.3 Optical absorption properties and band gap of hybrid organicinorganic perovskite materials Figure 3.22 Absorption spectra of perovskite films: perovskite CH3NH3PbI3, 2D/3D perovskite (5-AVA)x(MA)1-xPbI3, mixed perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 and double perovskite Cs2SnI6 From the absorption spectra of prepared perovskite materials, it can be seen that changing A cations does not significantly change the band gap of the material In addition, the results also show that perovskite CH 3NH3PbI3, 2D/3D perovskite (5-AVA)x(MA)1-xPbI3, mixed perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 and double perovskite Cs2SnI6 demonstrate a strong optical absorption, an adjustable band gap in the visible region, even up to the near infrared region (in case Cs 2SnI6) From the Tauc plots calculated from the absorption spectrum, we can determine the corresponding band gaps (1.27 eV ÷ 1.58 eV) which are suitable as light harvesters for solar cells 3.4 Characterization of the hetero-structured organic-inorganic perovskite materials and electron transport materials 3.4.1 MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 /TiO2/AuNPs Figures 3.26 and 3.27 Absorption and photoluminesence spectra of the mixed perovskite film MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 /TiO2/AuNPs with different Au film thicknesses Figure 3.26 shows the UV-VIS absorption spectrum of the perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3/TiO2/AuNPs perovskite films with different AuNPs layer thicknesses As can be seen, the absorption band edge is around 710 nm When the AuNPs metal nanolayer was coated on top of the TiO2 blocking layer, an absorption enhancement was observed with increasing thickness of the AuNPs layer Figure 3.27 shows photoluminesence spectra of MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3/TiO2/AuNPs perovskite films The PL emission intensity decreases with increasing number of Au metal nanolayers This PL quenching phenomena demonstrated that the presence of gold nanoparticles in the prepared samples increased the electron–hole separation 3.4.2 CH3NH3PbI3/ZnO nanorods The surface FE-SEM images of the heterostructured CH 3NH3PbI3/ZnO NRs showed that the films fabricated by the 2-step coating method had better coverage results, the perovskite material penetrated deeper into the nanorod porous structure to form larger crystals than one-step coating methods However, perovskite CH3NH3PbI3 decomposed rapidly due to the effect of strong photocatalytic properties of ZnO nanorod materials The degradation of the film is clearly shown by the color change of the film from black to yellow of PbI2 CHAPTER MANUFACTURING, SURVEYING OPERATION PARAMETERS OF HYBRID SOLAR CELLS USING THE ORGANIC INORGANIC PEROVSKITE AND NANO TIO2 ELECTRON TRANSPORT LAYER Chapter is presented in 22 pages including: 4.1 Design and fabrication of hybrid inorganic-organic perovskite hybrid solar cells Research and fabricate perovskite solar cells with different structures such as planar PSCs, mesoporous PSCs, and hole-transport-layer free perovskite solar cells (HTM-free PSCs) 4.2 Research results on planar perovskite solar cells (planar PSCs) Figures 4.5 and 4.6 Structural model design and FE-SEM crosssectional image of planar perovskite solar cells (planar PSCs) including layers: glass/FTO/bl-TiO2/AuNPs/triple cation perovskite/ SpiroOMeTAD/Au Figure 4.5 shows the structural model design and Figure 4.6 presents FE-SEM cross-sectional image of planar perovskite solar cells (planar PSCs) with prepared layers: glass/FTO/bl-TiO 2/AuNPs/triple cation perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3/Spiro-OMeTAD/Au The results of J-V characteristic curve measurement of planar hybrid organic-inorganic perovskite solar cells include the following layers: glass/FTO/bl-TiO2/AuNPs/ perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3/ SpiroOMeTAD/Au showed that samples coated with Au nanoparticles have higher efficiency Photovoltaic parameters of the planar hybrid organic-inorganic perovskite solar cells with different AuNPs coating thicknesses are presented in Table 4.1 Table 4.1 Photovoltaic parameters of the planar hybrid organic-inorganic perovskite solar cells with different AuNPs coating thicknesses Device samples AuNPs coating thicknesses (nm) M0 Voc Jsc (V) (mA/cm2) 0.46 M1 M2 M3 FF PCE (%) 1.6 0.51 0.38 0.51 1.9 0.56 0.54 0.72 3.1 0.63 1.41 10 0.70 2.8 0.61 1.20 From the measurement results, we can see that the M2 sample corresponding to the AuNPs coating thickness of nm gives the highest PCE efficiency of 1.41% This can be explained by the plasmonic effect that AuNPs scatters incident light and enhances charge transport The LSPR effect of AuNPs could support more incident photons on perovskite photoactive layer and thereby increases the charge carrier generation and separation, leading to improved device performance [118-120] 4.3 Research results (mesoporous PSCs) on mesoporous perovskite solar cells Figures 4.9 and 4.10 Cross-sectional FE-SEM image and J-V curves of mesoporous perovskite solar cells: glass/FTO/bl-TiO2 /mp-TiO2/perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3/Spiro-OMeTAD/Au with different mp-TiO2 layer thicknesses From Figure 4.9, the FE-SEM image of the cross-sectional device shows that we have fabricated a hybrid organic-inorganic perovskite solar cell device with mesoporous PSCs with following configuration: glass/FTO/ bl-TiO2 / mp-TiO2 / perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3 /SpiroOMeTAD/Au Perovskite crystals have penetrated the porous TiO layer creating good contact between the layers The J-V characteristic measurements (Figure 4.10) show that the thickness of the mp-TiO layer largely influences on the photovoltaic parameters Among samples, the 300 nm thickness mp-TiO2 gives the highest efficiency compared to other samples that reached 2.21%, nearly 1.6 times higher than the PCE of the planar perovskite solar cell without mp-TiO2 layer This can be explained that the mp-TiO2 layer with a thickness (~300 nm) will help the generated charge carriers in the perovskite to be well separated and increase the electron transport to the electrode without electron-hole recombination at the mp-TiO2/perovskite interface 4.4 Research results on hole-transport-layer free perovskite solar cells (HTM-free PSCs) In this thesis, hole-conductor free carbon-based perovskite solar cells were fabricated with the monolithic structure: glass/FTO/bl-TiO 2/(mpTiO2/mp-ZrO2/mp-carbon) perovskite The mixed 2D/3D perovskite precursor solution composed of PbI2, methylammonium iodide (MAI), and 5-ammoniumvaleric acid iodide (5-AVAI) was dropcasted through triple mesoporous TiO2/ZrO2/carbon electrode films We found that the isopropyl alcohol (IPA) solvent vapor annealing strongly influenced on the growth of mixed 2D/3D perovskite on triple mesoscopic layers It resulted in the better pore filling, better crystalline quality of perovskite layer, thus the improved stability and efficiency of perovskite solar cell was attributed to lower defect concentration and reduced recombination In this configuration, the carbon electrode layer used to replace the organic hole transport materials (HTMs) such as P3HT or Spiro-OMeTAD, which are very expensive Figure 4.12 Cross-sectional FE-SEM image of perovskite solar cell components without HTM layer using conventional annealing treatment TA (upper left) and annealing in isopropanol solvent vapor treatment SA (lower left) Optical absorption spectra (upper right) and J-V characteristic curves of solar cell components (lower right) using different annealing methods Figure 4.12 shows cross-sectional FE-SEM images of the completed device after coating 2D/3D perovskite (5-AVA) x(MA)1-xPbI3 by conventional annealing treatment (TA) and annealing in isopropanol solvent vapor treatment (SA) The FE-SEM images showed that the use of isopropanol (IPA) solvent annealing technique could supported the crystallization of 2D/3D perovskite (5-AVA)x(MA)1-xPbI3 materials on the porous structures Figure 4.13 Device architecture (a) and energy band diagram (b) and Figure 4.14 J–V curves of monolithic hole-conductor-free carbon-based perovskite solar cells prepared using thermal annealing (TA) and solvent vapor annealing (SA) The J-V characteristic curves of the monolithic hole-conductor-free perovskite solar cell using mixed 2D/3D perovskite prepared by thermal annealing (TA) and solvent vapor annealing (SA) were measured as shown in Figure 4.14 The photovoltaic parameters of these perovskite solar cells show the best device using mixed 2D/3D perovskite prepared by solvent vapor annealing (SA) The J-V curve of SA-device shows that solvent vapor annealing treatment significantly improved the device performance: Voc = 1.04V, Jsc = 12.54 mA/cm2, FF = 0.59 PCE = 7.69% CONCLUSION Inorganic - organic perovskite materials such as CH3NH3PbI3, multicomponent perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3, hybrid 2D/3D Perovskite, Pb-free double perovskite Cs2SnI6 have been successfully synthesized which exhibited strong absorption properties and suitable bandgaps Thin films of nanostructured semiconductor TiO and ZnO with controlled morphologies (compact or mesoporous nanoparticles, nanorods) have been successfully grown on conductive FTO/glass substrates as electron transport layers Au nanoparticles have been fabricated by thermal evaporation to study plasmonic effects such as better light traps and charge separation of the photo-generated carriers for improving the performance of perovskite solar cells The processes of manufacturing planar PSCs, mesoporous PSCs and hole-transport-layer free perovskite solar cells have been studied The obtained results showed that the isopropyl alcohol (IPA) solvent vapor annealing treatment strongly influenced on the growth of perovskite materials on triple mesoscopic layers thus improved stability and efficiency of hole-transport-layer free perovskite solar cells to 7,69%  ... of hybrid organicinorganic perovskite materials Figure 3.22 Absorption spectra of perovskite films: perovskite CH3NH3PbI3, 2D/3D perovskite (5-AVA)x(MA)1-xPbI3, mixed perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3... thesis: - Inorganic - organic perovskite materials such as CH3NH3PbI3, multicomponent perovskite MA0.2FA0.7Cs0.1Pb(I0.83Br0.17)3, hybrid 2D/3D Perovskite, Pb-free double perovskite Cs2SnI6 have been... Hybrid inorganic–organic perovskites have emerged as a promising class of materials for optoelectronic applications Therefore, this thesis focuses on researching and developing perovskite solar