Koenig Leandro Rodrigues, Batista Aline Domingues, Renzi Wesley, de Santana Henrique
Departamento de Química, CCE, Universidade Estadual de Londrina, Londrina, PR 86051- 990, Brazil.
Instituto Federal do Paraná, Pitanga, PR 85200-000, Brazil.
Heliyon. 2022 May 23;8(5):e09515. doi: 10.1016/j.heliyon.2022.e09515. eCollection 2022 May.
With the aim of verifying the optical properties of the systems formed by poly(3-methylthiophene) (P3MT) and poly(3-octylthiophene) (P3OT) on platinum (Pt) for use in organic photovoltaic device applications, electrochemical preparations of different interfaces with poly(3-alkylthiophenes) (P3ATs), synthesized both with 18 °C and without temperature control, were compared. These interfaces were prepared both as blends (Pt/P3MT:P3OT) and as layered films (Pt/P3MT/P3OT and Pt/P3OT/P3MT). Electrochemical impedance spectroscopy (EIS) was used to characterize the systems, and based on Bode-Phase diagrams, it was possible to monitor the stabilization of radical cation and dication segments of the thiophene ring. The findings corroborated previous studies by electrochemical spectroscopy and using Raman spectroscopy under the same experimental conditions. We were able to verify the effects of experimental variables, such as synthesis temperature and different kinds of deposition. Temperature was found to be an extremely important factor in synthesis, since films synthesized at 18 °C favored the stabilization of radical cation segments in the polymer matrix, and layered deposition also favored the stabilization of these segments, since the layer closest to the electrode can act as an induction layer for the stability of radical cation segments in the system. Photoluminescence spectroscopy was used to verify the optical properties of the interfaces, in which occur the contributions of three segments in the P3ATs matrix. Thus, it has been demonstrated through photoluminescence decay time that the relative amount of radical cation and dication segments in the polymer matrix affects the lifetime of these segments in the different materials prepared, due to emission effects for these systems.
为了验证由聚(3-甲基噻吩)(P3MT)和聚(3-辛基噻吩)(P3OT)在铂(Pt)上形成的体系用于有机光伏器件应用时的光学性质,比较了在18℃合成和无温度控制条件下合成的不同聚(3-烷基噻吩)(P3ATs)界面的电化学制备方法。这些界面既制备成共混物(Pt/P3MT:P3OT),也制备成层状膜(Pt/P3MT/P3OT和Pt/P3OT/P3MT)。采用电化学阻抗谱(EIS)对体系进行表征,基于波特相位图,可以监测噻吩环自由基阳离子和二价阳离子片段的稳定性。这些发现证实了之前在相同实验条件下通过电化学光谱和拉曼光谱进行的研究。我们能够验证实验变量的影响,如合成温度和不同的沉积方式。发现温度是合成过程中一个极其重要的因素,因为在18℃合成的薄膜有利于聚合物基体中自由基阳离子片段的稳定,层状沉积也有利于这些片段的稳定,因为最靠近电极的层可以作为体系中自由基阳离子片段稳定性的诱导层。采用光致发光光谱来验证界面的光学性质,其中P3ATs基体中有三个片段起作用。因此,通过光致发光衰减时间已经证明,由于这些体系的发射效应,聚合物基体中自由基阳离子和二价阳离子片段的相对量会影响所制备的不同材料中这些片段的寿命。