Short-length and high-density TiO{sub 2} nanorod arrays for the efficient charge separation interface in perovskite solar cells

Journal Article · Mon May 15 04:00:00 EDT 2017 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2017.03.005· OSTI ID:22658274

Xiao, Guannan; Shi, Chengwu; Zhang, Zhengguo; Li, Nannan; Li, Long

The TiO{sub 2} nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm{sup −2} were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI{sub 2}·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH{sub 3}NH{sub 3}I/CH{sub 3}NH{sub 3}Br=85/15. The perovskite solar cells based on the TiO{sub 2} nanorod array and 560 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO{sub 2} nanorod array and with 530 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer gave the best PCE of 12.82% at the relative humidity of 50–54%. - Graphical abstract: The TiO{sub 2} nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm{sup −2} were prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. The optimal annealing temperature of TiO{sub 2} nanorod arrays was 450 °C. The perovskite solar cells based on the TiO{sub 2} nanorod array and 560 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93% and the average PCE of 13.41±2.52%, while the corresponding planar perovskite solar cells without the TiO{sub 2} nanorod array and with 530 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer gave the best PCE of 12.82% and the average PCE of 10.54±2.28% at the relative humidity of 50–54%. - Highlights: • Preparation of TiO{sub 2} nanorod array with length of 70 nm and density of 1000 µm{sup −2}. • Influence of annealing temperatures on the -OH content of TiO{sub 2} nanorod arrays. • Preparation of over-500 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer. • Combination of short-length TiO{sub 2} nanorod array and high-thickness perovskite layer. • The best and average PCE with TiO{sub 2} array of 15.93% and 13.41±2.52% at 50–54% RH.

• OSTI ID: 22658274
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Vol. 249; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
77 NANOSCIENCE AND NANOTECHNOLOGY
AQUEOUS SOLUTIONS
DENSITY
EFFICIENCY
HYDROCHLORIC ACID
HYDROTHERMAL SYNTHESIS
LAYERS
LEAD IODIDES
NANOSTRUCTURES
OXIDATION
PEROVSKITE
SOLAR CELLS
TITANIUM OXIDES