Scholarlink

<p>To develop novel materials for improving the performance of organic solar cells (OSC), 17 molecules were designed as donor materials for OSC. These molecules employed triphenylamine as a donor unit, quinoxaline, 2–(thiophen–2–yl) quinoxaline, 2,3–bis(2–thienyl) quinoxaline, thieno[3,4–b] pyrazine, and thieno[3,4–b] quinoxaline as acceptor units, and benzene or thiophene as π-conjugated bridges. These 17 molecules were connected through three patterns: D–A–D, D–π–A–D, and D–π–A–π–D. Firstly, the optical and electronic properties of these donor materials at gas-phase ground state were calculated using the density functional theory. The highest occupied molecular orbital (HOMO) energies, energy gaps, and dipole moments were determined. The results showed that the HOMO energies of the designed molecules (S1–S17) ranged from –4.3 to –4.7&#xa0;eV, the energy gaps ranged from 1.4 to 2.9&#xa0;eV, and the dipole moments ranged from 0&#xa0;Debye to 1.7 Debye. Molecules linked by D–π–A–D and D–π–A–π–D patterns with benzene serving as the π-bridge exhibited larger energy gaps than those linked by the D–A–D pattern. When thiophene was used as the π-bridge, the opposite conclusion was obtained. Among these donor materials, S15–S17 with AM5 (thieno[3, 4–b]quinoxaline) as an acceptor unit demonstrated the smallest energy gaps, which favored electron transfer between donor and acceptor units. The Scharber model was utilized to predict photoelectric conversion efficiency (PCE) of these molecules, and it was found that the OSC with S15/PC<sub>61</sub>BM and S16/PC<sub>61</sub>BM as the active layer can achieve a PCE of 8% and 10%, respectively. Secondly, time-dependent density functional theory was employed to calculate the UV–Vis absorption spectra of these 17 donor materials. S15 and S16 with AM5 as an acceptor unit had the widest absorption spectral range. The UV–Vis absorption spectra of molecules linked by D–π–A–D and D–π–A–π–D patterns with benzene as the π–bridge exhibited blue shifts compared with those linked by D–A–D. The spectra showed red shifts and broader absorption ranges for D–π–A–D and D–π–A–π–D patterns compared with D–A–D when thiophene was the π–bridge. Finally, the ground-state and excited-state properties of these 17 donor materials were calculated in chloroform. The results showed that the dipole moments of all 17 molecules increased significantly, and their UV–Vis absorption spectra exhibited red shifts compared with gas-phase conditions.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Theoretical Study on Designed Triphenylamine-Based Donor Materials for Organic Solar Cells

  • 期刊论文

  • 发表日期：

    2025年11月7日

查看全文
  • Zhe Shi,
  • Hua Wu,
  • Yanjie Wang,
  • Wenqi Shi,
  • Yujie Zhao,
  • Hongyang Zhang,
  • Zhifan Wen,
  • Chenxiang Zhang,
  • Cailing Wang

摘要

To develop novel materials for improving the performance of organic solar cells (OSC), 17 molecules were designed as donor materials for OSC. These molecules employed triphenylamine as a donor unit, quinoxaline, 2–(thiophen–2–yl) quinoxaline, 2,3–bis(2–thienyl) quinoxaline, thieno[3,4–b] pyrazine, and thieno[3,4–b] quinoxaline as acceptor units, and benzene or thiophene as π-conjugated bridges. These 17 molecules were connected through three patterns: D–A–D, D–π–A–D, and D–π–A–π–D. Firstly, the optical and electronic properties of these donor materials at gas-phase ground state were calculated using the density functional theory. The highest occupied molecular orbital (HOMO) energies, energy gaps, and dipole moments were determined. The results showed that the HOMO energies of the designed molecules (S1–S17) ranged from –4.3 to –4.7 eV, the energy gaps ranged from 1.4 to 2.9 eV, and the dipole moments ranged from 0 Debye to 1.7 Debye. Molecules linked by D–π–A–D and D–π–A–π–D patterns with benzene serving as the π-bridge exhibited larger energy gaps than those linked by the D–A–D pattern. When thiophene was used as the π-bridge, the opposite conclusion was obtained. Among these donor materials, S15–S17 with AM5 (thieno[3, 4–b]quinoxaline) as an acceptor unit demonstrated the smallest energy gaps, which favored electron transfer between donor and acceptor units. The Scharber model was utilized to predict photoelectric conversion efficiency (PCE) of these molecules, and it was found that the OSC with S15/PC61BM and S16/PC61BM as the active layer can achieve a PCE of 8% and 10%, respectively. Secondly, time-dependent density functional theory was employed to calculate the UV–Vis absorption spectra of these 17 donor materials. S15 and S16 with AM5 as an acceptor unit had the widest absorption spectral range. The UV–Vis absorption spectra of molecules linked by D–π–A–D and D–π–A–π–D patterns with benzene as the π–bridge exhibited blue shifts compared with those linked by D–A–D. The spectra showed red shifts and broader absorption ranges for D–π–A–D and D–π–A–π–D patterns compared with D–A–D when thiophene was the π–bridge. Finally, the ground-state and excited-state properties of these 17 donor materials were calculated in chloroform. The results showed that the dipole moments of all 17 molecules increased significantly, and their UV–Vis absorption spectra exhibited red shifts compared with gas-phase conditions.