Thin Films Based on Cobalt Phthalocyanine:C60 Fullerene:ZnO Hybrid Nanocomposite Obtained by Laser Evaporation

Abstract

Matrix-assisted pulsed laser evaporation (MAPLE) was used to deposit hybrid nanocomposite thin films based on cobalt phthalocyanine (CoPc), C60 fullerene and ZnO nanoparticles. The inorganic nanoparticles, with a size of about 20 nm, having the structural and optical properties characteristic of ZnO, were chemically synthesized by a simple precipitation method. Furthermore, ZnO nanoparticles were dispersed in a dimethyl sulfoxide solution in which CoPc and C60 had been dissolved, ready for the freezing MAPLE target. The effect of the concentration of ZnO nanoparticles on the structural, morphological, optical and electrical properties of the CoPc:C60:ZnO hybrid nanocomposite layers deposited by MAPLE was evaluated. The infrared spectra of the hybrid nanocomposite films confirm that the CoPc and C60 preserve their chemical structure during the laser deposition process. The CoPc optical signature is recognized in the ultraviolet–visible (UV–Vis) spectra of the obtained layers, these being dominated by the absorption bands associated to this organic compound while the ZnO optical fingerprint is identified in the photoluminescence spectra of the prepared layers, these disclosing the emission bands linked to this inorganic semiconductor. The hybrid nanocomposite layers exhibit globular morphology, which is typical for the thin films deposited by MAPLE. Current-voltage (J-V) characteristics of the structures developed on CoPc:C60:ZnO layers reveal that the addition of an appropriate amount of ZnO nanoparticles in the CoPc:C60 mixture leads to a more efficient charge transfer between the organic and inorganic components. Due to their photovoltaic effect, structures featuring such hybrid nanocomposite thin films deposited by MAPLE can have potential applications in the field of photovoltaic devices.

Hybrid Nanocomposite Thin Films for Photovoltaic Applications: A Review

“…Recently, Socol (2020) used metal phthalocyanines (ZnPc, CoPc) and ZnO nanoparticles for developing hybrid layers for PV applications [ 44 , 64 ]. Thus, composite films based on a binary mixture (ZnPc and ZnO nanoparticles having ~30 nm in size) [ 44 ] or a ternary mixture (CoPc, C60 and ZnO nanoparticles with ~20 nm in size) [ 64 ] were deposited by MAPLE at a moderate laser fluence (350 mJ/cm 2 for ZnPc:ZnO blend and 240 mJ/cm 2 for CoPc:C60:ZnO blend), in both cases dimethyl sulfoxide being involved as the solvent in the preparation of the MAPLE target. The metal phthalocyanines concentration was kept constant (3% w / v ) while the ZnO nanoparticles concentration ( w / w ratio) was varied (P1 (1:0.15), P2 (1:0.35) and P3 (1:0.55) for ZnPc:ZnO mixture and P0 (1:1:0), P1 (1:1:0.25), P2 (1:1:0.75), and P3 (1:1:1) for CoPc:C60:ZnO mixture) in order to evaluate the influence of this parameter on the device performance.…”

“…Recently, the potential of a relatively new deposition technique, MAPLE, was evaluated for preparing hybrid layers based on PCPDTBT:CdSe QDs blends [ 65 ] and metal phtalocyanine:ZnO nanoparticle blends [ 44 , 64 ] for PV cells. Although the electrical performances are not impressive, the device performance can be enhanced by optimizing the parameters involved in the MAPLE deposition.…”

“…Laser-processing technique, i.e., Matrix-Assisted Pulsed Laser Evaporation (MAPLE) is a relatively new method being developed in the late 1990s by the US Naval Research Laboratory for processing organic compounds (especially polymers) layers with the preservation of their chemical structure during the deposition [ 59 ]. Thus, using small quantities of material (typically below 5 wt%), MAPLE allows the deposition of organic or hybrid layers for OPV [ 60 , 61 , 62 , 63 ] or HPV [ 44 , 64 , 65 ], respectively. Compared to the pulsed laser deposition (PLD), a technique employing a solid target obtained from pressed powder or pellets, MAPLE involves a frozen target prepared from the material that is intended to be deposit as thin film and a suitable solvent, used as matrix [ 66 , 67 ].…”

Structural and optical characteristics determined by the sputtering deposition conditions of oxide thin films

“…SiO 2 and ZnO films are obtained by various deposition techniques, such as matrix-assisted pulsed laser evaporation (MAPLE) [24,25], spin coating of sol-gel precursor solutions [26], radio-frequency magnetron sputtering (rfMS) [27][28][29][30], vacuum thermal evaporation (VTE) [31][32][33], chemical methods [34], reactive ion beam sputter deposition [35], among others. For example, SiO 2 and ZnO films obtained by rfMS can be either used as dielectric materials in metasurface structures or as dielectric interfaces in the structure of a metamaterial.…”

Structural and optical characteristics designed by sputtering deposition conditions of the oxide thin films

“…The SiO2 and ZnO films are obtained by various deposition techniques, such as: matrix-assisted pulsed laser evaporation (MAPLE) [24,25], spin coating of sol-gel precursor solutions [26], radio frequency magnetron sputtering (rfMS) [27][28][29][30], vacuum thermal evaporation (VTE) [31][32][33], chemical methods [34], reactive ion beam sputter deposition [35] etc. For example, SiO2 and ZnO films obtained by rfMS technique can be used as dielectric materials in metasurface structures, or as dielectric interfaces into the structure of a metamaterial.…”