Abstract
Anatase nanoparticles were synthesized from a titanium isopropoxide solution using a hydrothermal process at different pressures in an autoclave system while keeping the volume of the solution constant. As the autoclave pressure was increased from 1 to 71 atm (23 to 210 °C), the crystal size in the nanoparticles increased from 9 to 13.8 nm. The anatase nanoparticles were used to build dye-sensitized solar cells (DSSC). Mesoporous films of this oxide were deposited over conducting SnO2:F substrates using the screen-printing technique and then annealed at 530 °C at 1 atm of air pressure. The morphology of the mesoporous film surface of anatase, studied using scanning electron microscopy, revealed that the crystal size and pore distribution were functions of the pressure conditions. The energy band gap of the films as a function of the crystal size exhibited quantum effects below 11.8 nm. The effects of the anatase synthesis conditions and properties of the mesoporous film on the DSSC-type solar cell parameters, η%, VOC, JSC, and FF, were also investigated: the mesoporous anatase films prepared at 200 °C (54 atm of pressure in the autoclave) and annealed at 530 °C in air generated the best solar cell, having the highest conversion efficiency.
Highlights
Titanium dioxide (TiO2) is a width band gap semiconductor oxide with a wide spectrum of physical and chemical properties, among which we highlight the electrical conductivity, photosensitivity, photovoltaic activity, and chemical stability in acidic and aqueous environments
Based on the experimental results obtained for the mesoporous TiO2 mesoporous film (TiO2m) system, we studied the correlation between the quantum effect observed in the nanoparticles with crystal sizes below 11.8 nm and the experimental variables of the synthesis of the mesoporous system, namely pressure and temperature
Titanium oxide synthesis under a hydrothermal treatment generated samples primarily composed of the anatase phase, with crystallite sizes that increased linearly from 9 to 13.8 nm with increasing synthesis temperature
Summary
Titanium dioxide (TiO2) is a width band gap semiconductor oxide with a wide spectrum of physical and chemical properties, among which we highlight the electrical conductivity, photosensitivity, photovoltaic activity, and chemical stability in acidic and aqueous environments. In a process of charge carrier photogeneration, Because of its structural configuration consisting of layers and because a liquid-phase electrolyte is used, dye-sensitized solar cells constitute an electrochemical cell These cells use an n-type TiO2 semiconductor in the anatase phase in the blocking layer (compact layer) as well as in mesoporous layer forms. The blocking layer (TiO2b), with a thickness of 100 nm, can be prepared through sol–gel chemical deposition techniques, spin coating, and atomic layer deposition (ALD) The objective of this film is to block direct contact between the redox pair and the surface of the conducting glass, avoiding the construction of trap sites in the interface and reducing electronic recombination, which increases the efficiency of solar cells. Passivation through the compact layer has the advantage of reducing series resistance of the solar cell, as it improves contact between the mesoporous layer and the conducting glass
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
