Investigation of using amine and acetylamine functional units on naphthalimide dyes for photovoltaic devices

Abstract

Purpose The purpose of this paper is to introduce four new organic dyes based on naphthalimide for dye-sensitized solar cells (DSSCs). Design/methodology/approach Four new dyes based on naphthalimide with substitutions of amine and acetylamine in position C4 were designed in conjugation with substituted carbazole as donor–acceptor (D-A) architecture. The absorption and emission characteristics of the prepared dyes were evaluated in H2O, DMF and their mixture (DMF:H2O = 1:1). The feasibility of electron transfer in the DSSCs structure and energy levels were evaluated using electrochemical and density functional theory, which confirm the use of dyes in the DSSCs structure. The DSSCs were prepared using an individual strategy and their optical properties were investigated under the light of AM 1.5. Findings The prepared dyes exhibit orange color with strong emission at λem = 530–570 nm due to charge transfer with a positive solvatochromic effect. The efficiency of DSSCs based on Dye1-4 1 is: 3.69%, 3.71%, 4.69% and 4.76%. Therefore, the power efficiency increases by about 29 % in the presence of acetylamine group. Practical implications The design of new structures of organic dyes should be accompanied by the development of optical and electrical properties. In other words, in addition to the continuous production of electrons, efficient dyes must also be resistant to light to increase the life of the device. Social implications Organic dyes play a key role in the production of electrons in the DSSCs structure. The engineering of these structures and the introduction of widely used but low cost types can play an important role in the development of clean energy production. Originality/value The application of organic dyes based on naphthalimide was evaluated in the DSSCs structure and its photovoltaic properties were investigated.