TD-DFT investigation of small molecular donors for enhanced organic photovoltaics

IF 4 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Optical and Quantum Electronics Pub Date : 2025-09-22 DOI:10.1007/s11082-025-08454-z

A. Arunkumar, Xue-Hai Ju, Adeel Mubarik

{"title":"TD-DFT investigation of small molecular donors for enhanced organic photovoltaics","authors":"A. Arunkumar, Xue-Hai Ju, Adeel Mubarik","doi":"10.1007/s11082-025-08454-z","DOIUrl":null,"url":null,"abstract":"<div>Many researchers are becoming interested in using metal-free organic compounds (especially donor molecules) in photovoltaic (PV) devices nowadays. Considering the (E)-6-(benzofuran-2-yl)-3-(6-(benzofuran-2-yl)-1-(2-ethylhexyl)-2-oxoindolin-3-ylidene)-1-(2-ethylhexyl)indolin-2-one (IBF), seven new donor–acceptor–donor (D–A–D) with small molecular donors (SMDs) (IBF-D1 to IBF-D7) are designed and investigated for organic solar cells (OSCs) using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. With the MPW1PW91 functional and the 3-21G basis set being chosen, the theoretically calculated wavelengths (λmax) are presented. The molecular orbitals (MOs) energy gaps (Eg) of the compounds have values ranging from 2.22 to 2.42 eV. Specifically, the lowest Eg values are found in IBF-D1 (2.25 eV) and IBF-D6 (2.22 eV). Compared to IBF (2.19 eV), IBF-D2 and IBF-D7 show lower excitation energy differences (Ex). The derivatives (IBF-D1, IBF-D3, IBF-D4, IBF-D5, and IBF-D6) have the highest λmax values compared to IBF. The reorganization energies (RE) are between 0.0125–0.0195 eV for electron (λe) and 0.0019–0.0115 eV for hole mobilities (λh). Additional support for these findings comes from measurements of the transition density matrix (TDM) and molecular electrostatic potential (MEP). Compared to IBF (1.22 eV), IBF-D1 (1.24 eV), IBF-D4 (1.23 eV), and IBF-D6 (1.26 eV) have the highest open circuit voltage (Voc). The power conversion efficiency (PCE) values range from 0.83 to 1.13 %. In particular, IBF-D1 (1.11%) and IBF-D6 (1.13%) are superior PCEs of the OSCs. The nonlinear optical (NLO) parameters of the dipole moment (µ), polarizability (α), and first-order hyperpolarizability (β) for the molecules IBF-D1 (µ = 1.08 D, β = 1.70 esu, α = 5.00 esu) and IBF-D6 (µ = 3.40 D, α = 5.08 esu, β = 2.44 esu, respectively) are higher than those of IBF (µ = 0.84 D, α = 4.42 esu, β = 0.07 esu). Finally, IBF-D1 and IBF-D6 are highly advised to design organic PV with remarkable performance for the optoelectronic devices.</div>","PeriodicalId":720,"journal":{"name":"Optical and Quantum Electronics","volume":"57 10","pages":""},"PeriodicalIF":4.0000,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Optical and Quantum Electronics","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11082-025-08454-z","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}

引用次数: 0

Abstract

Many researchers are becoming interested in using metal-free organic compounds (especially donor molecules) in photovoltaic (PV) devices nowadays. Considering the (E)-6-(benzofuran-2-yl)-3-(6-(benzofuran-2-yl)-1-(2-ethylhexyl)-2-oxoindolin-3-ylidene)-1-(2-ethylhexyl)indolin-2-one (IBF), seven new donor–acceptor–donor (D–A–D) with small molecular donors (SMDs) (IBF-D1 to IBF-D7) are designed and investigated for organic solar cells (OSCs) using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. With the MPW1PW91 functional and the 3-21G basis set being chosen, the theoretically calculated wavelengths (λ_max) are presented. The molecular orbitals (MOs) energy gaps (E_g) of the compounds have values ranging from 2.22 to 2.42 eV. Specifically, the lowest E_g values are found in IBF-D1 (2.25 eV) and IBF-D6 (2.22 eV). Compared to IBF (2.19 eV), IBF-D2 and IBF-D7 show lower excitation energy differences (E_x). The derivatives (IBF-D1, IBF-D3, IBF-D4, IBF-D5, and IBF-D6) have the highest λ_max values compared to IBF. The reorganization energies (RE) are between 0.0125–0.0195 eV for electron (λ_e) and 0.0019–0.0115 eV for hole mobilities (λ_h). Additional support for these findings comes from measurements of the transition density matrix (TDM) and molecular electrostatic potential (MEP). Compared to IBF (1.22 eV), IBF-D1 (1.24 eV), IBF-D4 (1.23 eV), and IBF-D6 (1.26 eV) have the highest open circuit voltage (V_oc). The power conversion efficiency (PCE) values range from 0.83 to 1.13 %. In particular, IBF-D1 (1.11%) and IBF-D6 (1.13%) are superior PCEs of the OSCs. The nonlinear optical (NLO) parameters of the dipole moment (µ), polarizability (α), and first-order hyperpolarizability (β) for the molecules IBF-D1 (µ = 1.08 D, β = 1.70 esu, α = 5.00 esu) and IBF-D6 (µ = 3.40 D, α = 5.08 esu, β = 2.44 esu, respectively) are higher than those of IBF (µ = 0.84 D, α = 4.42 esu, β = 0.07 esu). Finally, IBF-D1 and IBF-D6 are highly advised to design organic PV with remarkable performance for the optoelectronic devices.

查看原文本刊更多论文

增强有机光伏小分子给体的TD-DFT研究

目前，许多研究人员对在光伏（PV）器件中使用无金属有机化合物（特别是供体分子）产生了兴趣。考虑到(E)-6-（苯并呋喃-2-基）-3-（6-（苯并呋喃-2-基）-1-（2-乙基己基）-2-氧吲哚啉-3-酰基）-1-（2-乙基己基）吲哚啉-2- 1 (IBF)，利用密度泛函理论（DFT）和时间依赖DFT （TD-DFT）方法设计并研究了有机太阳能电池（OSCs）中7种具有小分子供体（IBF- d1至IBF- d7）的新供体-受体-供体（D-A-D）。在MPW1PW91功能和选择3-21G基组的情况下，给出了理论计算波长（λmax）。化合物的分子轨道（MOs）能隙（Eg）在2.22 ~ 2.42 eV之间。其中，IBF-D1 （2.25 eV）和IBF-D6 （2.22 eV）的Eg值最低。与IBF （2.19 eV）相比，IBF- d2和IBF- d7的激发能差（Ex）较小。与IBF相比，IBF- d1、IBF- d3、IBF- d4、IBF- d5和IBF- d6的λmax值最高。电子重组能（λe）为0.0125 ~ 0.0195 eV，空穴迁移能（λh）为0.0019 ~ 0.0115 eV。对这些发现的额外支持来自过渡密度矩阵（TDM）和分子静电势（MEP）的测量。与IBF （1.22 eV）相比，IBF- d1 （1.24 eV）、IBF- d4 （1.23 eV）和IBF- d6 （1.26 eV）具有最高的开路电压（Voc）。功率转换效率（PCE）取值范围为0.83 ~ 1.13%。特别是IBF-D1（1.11%）和IBF-D6（1.13%）是OSCs的优势pce。分子IBF- d1（µ= 1.08 D, β = 1.70 esu, α = 5.00 esu）和IBF- d6（µ= 3.40 D, α = 5.08 esu, β = 2.44 esu）的偶极矩（µ）、极化率（α）和一阶超极化率（β）的非线性光学参数均高于分子IBF（µ= 0.84 D, α = 4.42 esu, β = 0.07 esu）。最后，我们强烈建议IBF-D1和IBF-D6为光电器件设计具有卓越性能的有机光伏。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Optical and Quantum Electronics 工程技术-工程：电子与电气

CiteScore

4.60

自引率

20.00%

发文量

810

审稿时长

3.8 months

期刊介绍： Optical and Quantum Electronics provides an international forum for the publication of original research papers, tutorial reviews and letters in such fields as optical physics, optical engineering and optoelectronics. Special issues are published on topics of current interest. Optical and Quantum Electronics is published monthly. It is concerned with the technology and physics of optical systems, components and devices, i.e., with topics such as: optical fibres; semiconductor lasers and LEDs; light detection and imaging devices; nanophotonics; photonic integration and optoelectronic integrated circuits; silicon photonics; displays; optical communications from devices to systems; materials for photonics (e.g. semiconductors, glasses, graphene); the physics and simulation of optical devices and systems; nanotechnologies in photonics (including engineered nano-structures such as photonic crystals, sub-wavelength photonic structures, metamaterials, and plasmonics); advanced quantum and optoelectronic applications (e.g. quantum computing, memory and communications, quantum sensing and quantum dots); photonic sensors and bio-sensors; Terahertz phenomena; non-linear optics and ultrafast phenomena; green photonics.