Growth of films with seven-coordinated diorganotin(IV) complexes and PEDOT:PSS structurally modified for electronic applications

Abstract

This work refers to the manufacture and characterization of organic electronic devices made from seven-coordinated diorganotin(IV) complexes and the polymer poly(3,4-ethylenedyoxithiophene)-poly(styrene sulfonate) (PEDOT:PSS). In order to obtain the best electronic behavior, the devices were manufactured by spin-coating with seven-coordinated diorganotin(IV) complexes, synthetized with different peripheral substituents. The modification of the polarity in the molecule, from the presence of the different functional groups, is used as a way to enhance the charge transport inside the devices. Additionally, the devices received a post-treatment with isopropyl alcohol, in order to change the structure of PEDOT:PSS from benzoid form to quinoid form. The electric charge transport was evaluated from the current density–voltage characteristics, under dark and illuminated conditions. The devices present a mobility of ∼10−9 cm2/Vs decreasing to values of ∼10−11–10−10 cm2/Vs. They display a photocurrent of ∼10−7–10−8 A cm−2 and a reduction is observed after the treatment. It is mainly the presence of the peripheral substituents in the diorganotin(IV) complexes, and not the polymer structure, that causes the electrical behavior of the device. The films made from seven-coordinated diorganotin(IV) complex particles deposited on the PEDOT:PSS, as well as their post-treatment, were characterized by Raman, ultraviolet-vis spectroscopy, scanning electronic microscopy and atomic force microscopy.

Fabrication and Characterization of Hybrid Hole Transporting Layers of Organotin (IV) Semiconductors within Molybdenum Oxide/Poly(3,4-ethylenedyoxithiophene) Polystyrene Sulfonate Matrices

“…The presence of the bromide in this complex, with an electro-attracting capability greater than A and less than C, promotes intermolecular and intramolecular electronic transitions, without generating charge polarization. On the other hand, it is important to mention that the value of 3.42 eV obtained for the film with the C-complex is similar to the E opt obtained for thin films in PEDOT:PSS, with heptacoordinated organotin (IV) complexes having substituents that can be both electro-attractors and electro-donors [ 57 , 58 ], as previously studied by some authors of this work. With respect to hybrid films with a PEDOT:PSS matrix and graphene and organotin (IV)-based semiconductor complexes with electro-attracting substituents, such as chloride [ 59 ], and for the organotin Schiff bases in spun films applied in organic solar cells [ 60 ], the E opt obtained for the films with the A and B-complexes presents similar values and, in all cases, less than that of the film with the C-complex.…”

Pentacoordinated Organotin(IV) Complexes as an Alternative in the Design of Highly Efficient Optoelectronic and Photovoltaic Devices: Synthesis and Photophysical Characterization

“…The two transitions are smaller for the film with complex 1c , which has a phenyl substituent in its structure. The obtained values are of the same magnitude order as those for heptacoordinated tin(IV) complexes embedded in PEDOT:PSS and graphene ( = 1.13–1.29 eV and Eg = 2.83–3.47 eV) [ 29 , 30 , 60 ]. They are also within the range for inorganic semiconductors.…”

“…Organotin(IV) complexes have also been reported as sensitizers [ 25 ], PVC stabilizers [ 26 ], fungicides, catalysts, and active electroluminescent layers in organic light-emitting diodes (OLEDs) [ 27 ]. In addition, organotin(IV) complexes can be used in the manufacture of semiconductor films, in which their electrical conductivity can be increased by adding substituents to their molecular structure [ 28 , 29 , 30 ]. Charge transport is present in organotin(IV) films due to their π-conjugated structures and the presence of electronegative atoms and substituents coordinated to the tin atom [ 31 ].…”

Deposition and Characterization of Innovative Bulk Heterojunction Films Based on CuBi2O4 Nanoparticles and Poly(3,4 ethylene dioxythiophene):Poly(4-styrene sulfonate) Matrix

“…Additionally, these results indicate a higher conductivity compared to other 2D/PEDOT:PSS composite materials [4]. According to Pasha et al [52][53][54][55][56][57][58][59][60][61][62][63][64][65], the reason for the improvement in the conductivity in PEDOT:PSS/CuBi 2 O 4 NPs films can be attributed to the formation of more charge carriers, due to the large interfacial area in the polymer, and to the fact that the charge carriers also find electrical pathways to easily hop between the PEDOT and PSS polymer chains. Additionally, the NP-polymer interface promotes the generation of electron/hole pairs.…”

“…The latter indicates that the device starts operating at a very low voltage with an exponential output, and that also the device operation is close to the ideal diode where the ideality factor equals 1, which is evidence of its proper function as a photovoltaic device, as a consequence of an efficient charge separation and transport. On the other hand, the device characteristic presents three different conduction mechanisms: ohmic behavior, trapped charge limited current (T-CLC) and space charge limited current (SCLC) [56], which affect the resulting conductivity at different applied voltages. The resulting curve shows a current variation between 10 −9 and 10 −5 A (0 to 1.5 V), as it can be observed in the semi-logarithmic curve inset.…”