Search results for "heterojunction"

Bulk heterojunctions by boramers for plastic photovoltaics

2009

Enhanced Efficiency of Organic Solar Cells by Thiol-capped Au-Nanoparticles

2015

In this work, we present a study on the effect of thiol-capped AuNPs of various sizesin an organic solar cell.AuNPs have been obtained by laser ablation in liquid solution[2], have been functionalized both with 2-naphthalenethiol and alkanethiol having different length. In addition to bulk heterojunction structures with optimized interpenetrating network of donors and acceptor domains, we have chosen to study planar heterojunctions (PHJs), consisting of three component thin films realized by sequential deposition of P3HT, AuNPs and PCBM from orthogonal solvents.

Enhancing triplet superconductivity by the proximity to a singlet superconductor in oxide heterostructures

2016

We show how in principle a coherent coupling between two superconductors of opposite parity can be realized in a three-layer oxide heterostructure. Due to strong intraionic spin-orbit coupling in the middle layer, singlet Cooper pairs are converted into triplet ones and vice versa. This results in a large enhancement of the triplet superconductivity, persisting well above the native triplet critical temperature.

TiO2/Ag2O immobilized on cellulose paper: A new floating system for enhanced photocatalytic and antibacterial activities

2021

Paper-TiO2-Ag2O floating photocatalysts were produced under mild condition and their photocatalytic activity for the degradation of aromatic amine under sunlight stimulant was investigated. Characterizations by Raman, XRD, XPS, DRS and PL confirmed the presence of TiO2 and Ag2O, and the morphology of the appended TiO2/Ag2O layer was probed by FE-SEM. The photocatalytic activity of the prepared samples was investigated by the degradation of aniline (AN) in water under simulated sun-light illumination and constrained conditions, i.e. non-stirring and non-oxygenation. The presence of Ag2O combined with TiO2 was shown to improve the resistance of paper to bacteria attack, thus increasing the du…

Ferroelectric Properties and Crystal Structure of YBa2Cu3O7/BaxSr(1−x)TiO3 Heterostructures

1997

ABSTRACTEpitaxial YBa2Cu3O7/Ba0.5Sr0.5TiO3 (YBCO/BST) and YBCO/BaTiO3 (BTO) heterostructures were prepared by dc and rf sputtering on SrTiO3 and MgO substrates. The YBCO/BTO bilayers exhibit an inductive superconducting transition temperature of 85 K and the ferroelectric phase transition of BST shows a Curie-Weiss temperature of 310 K. Microstructure was investigated by x-ray-diffraction and atomic force microscopy. In this work we also studied the insulator's conductivity and the contribution of domain walls to permittivity.

Control of the Magnetic Configuration of Ferromagnetic Nanostructures Across the Structural Phase Transition of Vanadium Dioxide

2016

We investigate the effect of the structural phase transition in VO 2 in magnetoelastically coupled heterostructures of VO 2 and Ni. Continuous and nano-patterned Ni layers were used, and we found reversible and reproducible magnetic domain switching induced by the VO 2 structural phase transition. The magnetic states of the nano-patterned ferromagnetic elements were dominated by topographic features which generated strong pinning but still allowed for a reversible switching between the states. Our measurements constitute a key step for the use of the VO 2 phase transition for ultrafast dynamical studies of the inverse mangetostrictive effect, and eventually employing the effect for ultrafas…

Magnetic and electronic phase transitions probed by nanomechanical resonators

2020

The reduced dimensionality of two-dimensional (2D) materials results in characteristic types of magnetically and electronically ordered phases. However, only few methods are available to study this order, in particular in ultrathin insulating antiferromagnets that couple weakly to magnetic and electronic probes. Here, we demonstrate that phase transitions in thin membranes of 2D antiferromagnetic FePS3, MnPS3 and NiPS3 can be probed mechanically via the temperature-dependent resonance frequency and quality factor. The observed relation between mechanical motion and antiferromagnetic order is shown to be mediated by the specific heat and reveals a strong dependence of the Néel temperature of…

Photoelectrochemical Evidence of Cu2O/TiO2 Nanotubes Hetero-Junctions formation and their Physicochemical Characterization

2014

Cu2O/TiO2 nanotubes heterojunctions were fabricated by electrochemical deposition of cuprous oxide on TiO2 nanotubes arrays grown by anodizing. X-ray diffraction and Raman Spectroscopy analysis allows for identification of Cu2O, whose morphological features were studied by Scanning Electron Microscopy as a function of the charge circulated during the electrodeposition step. Photoelectrochemical measurements in aqueous solutions evidenced a red shift of the light absorption threshold of TiO2 nanotubes due to the presence of cuprous oxide even for very low circulated charges, while electrochemical impedance measurements proved a significant reduction of the electrode impedance due the presenc…

Consequences of the spatial localization on the exciton recombination dynamics in InGaP/GaAs heterostructures

2002

5 páginas, 4 figuras.

Different temperature renormalizations for heavy and light-hole states of monolayer-thick heterostructures

2000

Abstract We have found that the energy splitting between peaks in the linearly polarized emission from the cleaved surface of an InAs/GaAs monolayer structure triples with increasing temperature in the range from 5 to 150 K. For each polarization the main emission line corresponds to the radiative recombination of either heavy or light-hole excitons bound to the monolayer. The striking temperature behavior of the peak energies originates from the different hole–phonon coupling due to the much larger penetration of the light-hole envelope function into the GaAs. We prove this assertion by confining the light holes to the InAs plane with a strong magnetic field, which leads to a reduction of …