13:30 〜 15:30
[13p-PA3-10] Development of Tetrabenzoporphyrin-Based Non-Fullerene Acceptor Molecules That Can Be Processed via a Thermal-Precursor Approach
キーワード：non-fullerene acceptors, thin-film morphology, single-crystal X-ray structures
Tetrabenzoporphyrin (BP) holds attractive characteristics for optoelectronics applications, such as the large, rigid π-conjugated framework and high photoabsorption capability. Although BP has poor solubility in any solvents, thin films of BP can be prepared by depositing soluble precursor CP as a solution and then heating it to induce the retro-Diels–Alder reaction in situ (Scheme 1). This "thermal precursor approach" would enable straightforward molecular design and clearer understanding of the structure–property relationship because it largely reduces the need for solubilizing groups that often obscure electronic properties of semiconducting molecules in the thin-film state.
In this work, 2CF3BP, 4CF3BP and pCNBP equipped with multiple strongly electron-withdrawing groups have been designed (Fig. 1a), and evaluated as non-fullerene acceptors in organic solar cells (OSCs). These compounds are deposited via the thermal precursor approach together with a common donor polymer, either P3HT or PTB7, to form bulk-heterojunction (BHJ)-type active layers. The resulting devices show clear photovoltaic response, proving that the new BP derivatives serve as acceptor in OSCs (Fig. 1b and Table 1). Although the power conversion efficiencies (PCEs) are rather limited (2.04% at best), this result is an important step in developing a novel class of non-fullerene acceptors for OSCs. Further, this is the first example wherein the thermal precursor approach is successfully employed for the preparation of polymer–small molecule blend films, thereby extending its scope of applicability. In this presentation, we will discuss in detail the relationship among the molecular structure, electronic properties, and thin-film morphology.
In this work, 2CF3BP, 4CF3BP and pCNBP equipped with multiple strongly electron-withdrawing groups have been designed (Fig. 1a), and evaluated as non-fullerene acceptors in organic solar cells (OSCs). These compounds are deposited via the thermal precursor approach together with a common donor polymer, either P3HT or PTB7, to form bulk-heterojunction (BHJ)-type active layers. The resulting devices show clear photovoltaic response, proving that the new BP derivatives serve as acceptor in OSCs (Fig. 1b and Table 1). Although the power conversion efficiencies (PCEs) are rather limited (2.04% at best), this result is an important step in developing a novel class of non-fullerene acceptors for OSCs. Further, this is the first example wherein the thermal precursor approach is successfully employed for the preparation of polymer–small molecule blend films, thereby extending its scope of applicability. In this presentation, we will discuss in detail the relationship among the molecular structure, electronic properties, and thin-film morphology.