Extremely Large Magnetic-Field-Effects on the Impedance Response of TiO2 Quantum Dots

On the Donor: Acceptor Features for Poly(3-hexylthiophene): TiO2 Quantum Dots Hybrid Materials Obtained via Water Vapor Flow Assisted Sol-Gel Growth

Here, we present a novel methodology for the preparation of P3HT:TiO₂ quantum dots hybrid materials via water vapor flow-assisted sol-gel growth focusing on the structural, optical and electrical property characterization complemented with first-principles calculations as a promising donor-acceptor system for polymer and hybrid solar cells. X-ray diffraction and UV-Vis spectroscopy analyses suggest that the increasing concentration of TiO₂ quantum dots leads to the formation of higher amounts of amorphous regions while the crystalline regions exhibited interesting aspect ratio modifications for the P3HT polymer. Raman spectra evidenced the formation of charge carriers in the P3HT with increasing TiO₂ quantum dots content and the P3HT:TiO₂ 50:50 weight ratio resulted in the best composition for optimizing the bulk electronic conductivity, as evidenced by impedance spectroscopy studies. Our DFT calculations performed for a simplified model of the P3HT:TiO₂ interface revealed that there is an important contribution of the thiophene carbon atoms states in the conduction band at the Fermi level. Finally, our DFT calculations also reveal an evident gain of electron density at the TiO₂ (101) surface while the thiophene rings showed a loss of the electron density, thus confirming that the P3HT:TiO₂ junction acts as a good donor-acceptor system. In our opinion, these results not only present a novel methodology for the preparation of P3HT:TiO₂ quantum dots hybrid materials but also reveal some key aspects to guide the more rational design of polymer and hybrid solar cells.

Hybrid Organic-Inorganic Materials and Interfaces With Mixed Ionic-Electronic Transport Properties: Advances in Experimental and Theoretical Approaches

The main goal of this mini-review is to provide an updated state-of-the-art of the hybrid organic-inorganic materials focusing mainly on interface phenomena involving ionic and electronic transport properties. First, we review the most relevant preparation techniques and the structural features of hybrid organic-inorganic materials prepared by solution-phase reaction of inorganic/organic precursor into organic/inorganic hosts and vapor-phase infiltration of the inorganic precursor into organic hosts and molecular layer deposition of organic precursor onto the inorganic surface. Particular emphasis is given to the advances in joint experimental and theoretical studies discussing diverse types of computational simulations for hybrid-organic materials and interfaces. We make a specific revision on the separately ionic, and electronic transport properties of these hybrid organic-inorganic materials focusing mostly on interface phenomena. Finally, we deepen into mixed ionic-electronic transport properties and provide our concluding remarks and give some perspectives about this growing field of research.