Effect of UV-activated TiO₂ Nanoparticles on the Properties and Performance of PAni-TiO₂ Nanocomposite Films for Solar Cell Applications

Abstract

To improve the performance of organic solar cells by enhancing the properties of the photoactivated nanocomposite layer, the UV irradiation process was used to activate titanium dioxide nanoparticles (TiO2 NPs). Herein, polymer solar cells were fabricated with FTO/(PAni-TiO2)/Ag system. A series of mixed polyaniline (PAni) with 20% of activated TiO2 NPs at different processing times was used to form PAni-TiO2 nanocomposite films. The structural evolution, surface characteristics, optical and electrical properties of PAni-TiO2 films have been investigated. XRD patterns showed that the UV treatment of TiO2 NPs increased the crystallite from 18.35 to 24.1 nm and the degree of crystallinity increased by 5.6%. The irradiated PAni-TiO2 films showed a rougher and more porous surface compared to the untreated one. Moreover, the adhesion force and electrical conductivity of the treated nanocomposite films at 8 h improved to be 137 mN/m and 6.62 S/m, respectively. Incorporation of activated TiO2 NPs exposure to UV for different times from 0 to 8 h with the PAni matrix enhanced the current density (Jsc) of PAni-TiO2 based nanocomposite solar cells from 3.11 to 4.83 (mA/cm2) and their efficiency from 0.33 to 0.85%. The increase in the solar cell efficiency is mostly ascribed to a structural change accompanied by a rapid increase in surface roughness, which led to a decrease in the reflected photons and thus an increase in the charge carriers produced. These results revealed the effect of surface UV irradiation of TiO2 NPs on their structural properties and the electronic contact between PAni and TiO2 NPs, which greatly influenced the amount of carrier transport within the PAni-TiO2 composites.

Photoresponsive Electrospun Fiber Meshes with Switchable Wettability for Effective Fog Water Harvesting in Variable Humidity Conditions

“…UV irradiation produces photogenerated holes (h+) and electrons (e−) (Figure b). The photogenerated holes directly attack the surface Ti–O bonds, breaking them apart in coordination with H 2 O …”

“…The photogenerated holes directly attack the surface Ti–O bonds, breaking them apart in coordination with H 2 O. 62 …”

“…The photogenerated holes directly attack the surface Ti−O bonds, breaking them apart in coordination with H 2 O. 62 The switching UV wettability was demonstrated by measuring the water contact angle along with increasing UV irradiation time (Figure 3c). The sample with the most TiO 2 , PVDF-TiO 2 -Blend-CS-Espray, exhibited a decrease in contact angle and turned superhydrophilic after 90 min of UV irradiation.…”

Titanium Dioxide (TiO2) Concentration-dependent Photovoltaic Cells Performance of PAni-TiO2 Nanocomposite

“…TiO 2 NPs were synthesized chemically using a hydrothermal method [1]. To prepare PAni-TiO 2 composites, different weight of TiO 2 nanopowders (20, 25, and 33%) were mixed to the unmodified PAni solution during the chemical oxidative polymerization process of aniline monomer [14]. Then, the synthesized composites of PAni-TiO 2 were deposited via a spin-coater device on FTO (81-84% transmittance and 4.1 x 10 -5 Ω.cm resistivity, sigma Aldrich) coated conducting substrates using an 800 rpm for 30s.…”

Preparation and Photovoltaic Performance of a Composite TiO2 Nanotube Array/Polyaniline UV Photodetector

“…UV photodetectors have emerged as an increasingly popular topic in science research in recent years [1,2]. Due to their excellent performance with a high sensitivity, wide linear range, and good stability, UV photodetectors in the mid-ultraviolet and near-ultraviolet wavelength bands are widely used in important fields, including military and defense [3], biomedicine [4,5], environmental monitoring [6], and light wave communication [7]. The focus of study has steadily shifted to the utilization of UV radiation from fires or sunlight for ozone hole and fire monitoring.…”