Organic-inorganic Co-addition to Improve Mechanical Bending and Environmental Stability of Flexible Perovskite Solar Cells

doi:10.15541/jim20230532

Abstract

Abstract:

Recently, perovskite solar cells have developed marvelously of which power conversion efficiency (PCE) achieved 26.1%, but the mechanical bending and environmental stability of flexible perovskite solar cells (F-PSCs) have remained major obstacles to their commercialization. In this study, the quality and crystallization of perovskite thin films were enhanced by adding agarose (AG). The interaction mechanism, PCE, mechanical bending and environmental stability of the assembled F-PSCs were investigated. It was found that the perovskite films modified by the optimal concentration of AG (3 mmol/L) exhibited denser and smoother morphology, higher crystallinity and absorbance, the lowest defect state density, and lower charge transfer resistance of 2191 Ω. Based on the optimal photoelectric properties, PCE increased from 15.17% to 17.30%. TiO₂ nanoparticles (0.75 mmol/L) were further introduced to form a synergistic interaction with AG (3 mmol/L), which provided a rigid backbone structure, and thus enhanced the mechanical and environmental stability of perovskite layers. After 1500 cycles of bending (3 mm in radius), the AG/TiO₂ co-modified F-PSCs maintained 84.73% of initial PCE, much higher than the blank device (9.32%). After 49 d in the air, the optimal F-PSCs still maintained 83.27% of initial PCE, superior than the blank device (62.21%). This work provides possibility for preparing highly efficient and stable F-PSCs.

Key words: flexible perovskite solar cell, additive engineering, bending stability, environmental stability

CLC Number:

O646

CHEN Tian, LUO Yuan, ZHU Liu, GUO Xueyi, YANG Ying. Organic-inorganic Co-addition to Improve Mechanical Bending and Environmental Stability of Flexible Perovskite Solar Cells[J]. Journal of Inorganic Materials, 2024, 39(5): 477-484.

Figures/Tables 10

Fig. 1 Morphologies, crystal structure and optical properties of xAG-P (x=0, 3, 6, 9, 12) films deposited on ITO-PEN/SnO2 (a-e) SEM images; (f) XRD patterns; (g) UV-Vis absorption spectra; (h) Tauc plots; (i) Photoluminescence emission Colorful figures are available on website

Fig. 2 (a) C1s, (b) Pb4f, (c) I3d, (d) N1s, and (e) O1s XPS spectra of xAG-P (x=0, 3, 6, 9, 12) films, and (f) FT-IR spectra of AG, 0AG-P, and 3AG-P films

Fig. 3 Photovoltaic performance and stability of xAG-PSC (x=0, 3, 6, 9, 12) (a) J-V curves; (b) External quantum efficiency (EQE) curves; (c) I-V plots based on space charges limit current model; (d) Nyquist plots; (e) Bending stability; (f) Environmental stability Colorful figures are available on website

Fig. 4 Morphologies, crystal structure, and optical properties of 3AG-yTiO2-P (y=0, 0.75, 1.50, 2.25, 3.00) films deposited on ITO-PEN /SnO2 (a-e) SEM images; (f) XRD patterns; (g) UV-Vis absorption spectra; (h) Photoluminescence emission spectra; (i) FT-IR spectra of TiO2, AG, AG-TiO2, 0AG-P, 3AG-P, and 3AG-0.75TiO2-P films Colorful figures are available on website

Fig. 5 (a) Bending stability and (b) environmental stability of 3AG-yTiO2-PSC (y=0, 0.75, 1.50, 2.25, 3.00) Colorful figures are available on website

Table S1 FWHM of XRD peaks of MAPbI3 films modified with different agarose concentrations/(°)

Sample	FWHM₍₁₁₀₎	FWHM₍₂₂₀₎	FWHM₍₃₁₀₎	FWHM₍₃₂₁₎
0AG-P	0.220	0.183	0.196	0.271
3AG-P	0.165	0.136	0.149	0.257
6AG-P	0.210	0.146	0.156	0.261
9AG-P	0.208	0.199	0.156	0.260
12AG-P	0.239	0.221	0.223	0.276

Table S2 Stretching vibration peaks corresponding to the main functional groups of AG, 0AG-P abd 3AG-P

Sample	ν_C−O−C/cm⁻¹	ν_O−H/cm⁻¹	ν_N−H/cm⁻¹
AG	1076	3444
0AG-P			1452
3AG-P			1454

Table S3 Photoelectric performance parameters of F-PSCs based on MAPbI3 films with different agarose concentrations

Sample	J_sc/(mA·cm^-2)	V_oc/V	FF/%	PCE/%
0AG-PSC	19.66	1.09	70.58	15.17
3AG-PSC	22.89	1.06	71.12	17.30
6AG-PSC	20.17	1.06	64.18	13.65
9AG-PSC	18.31	1.03	68.45	12.86
12AG-PSC	17.53	1.00	64.35	11.20

Table S4 FWHM of XRD peaks of MAPbI3 films modified with different concentrations of TiO2/(°)

Sample	FWHM₍₁₁₀₎	FWHM₍₂₂₀₎	FWHM₍₃₁₀₎	FWHM₍₃₂₁₎
3AG-0TiO₂-P	0.165	0.136	0.149	0.257
3AG-0.75TiO₂-P	0.188	0.183	0.196	0.255
3AG-1.50TiO₂-P	0.169	0.193	0.189	0.263
3AG-2.25TiO₂-P	0.146	0.169	0.174	0.254
3AG-3.00TiO₂-P	0.161	0.179	0.189	0.246

Table S5 Stretching vibration peaks corresponding to the main functional groups of TiO2, AG, TiO2-AG 0AG-P, 3AG-P and 3AG-0.75TiO2-P

Sample	ν_C−O−C/cm⁻¹	ν_O−H/cm⁻¹	ν_C−H/cm⁻¹	ν_N−H/cm⁻¹
TiO₂		3415
AG	1076	3444
TiO₂-AG	1099	3448
0AG-P			2871	1452
3AG-P			2873	1454
3AG-0.75TiO₂-P			2873	1456

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