73540-75-7Relevant articles and documents
A Facile Synthesized Polymer Featuring B-N Covalent Bond and Small Singlet-Triplet Gap for High-Performance Organic Solar Cells
Pang, Shuting,Wang, Zhiqiang,Yuan, Xiyue,Pan, Langheng,Deng, Wanyuan,Tang, Haoran,Wu, Hongbin,Chen, Shanshan,Duan, Chunhui,Huang, Fei,Cao, Yong
supporting information, p. 8813 - 8817 (2021/03/16)
High-efficiency organic solar cells (OSCs) largely rely on polymer donors. Herein, we report a new building block BNT and a relevant polymer PBNT-BDD featuring B-N covalent bond for application in OSCs. The BNT unit is synthesized in only 3 steps, leading to the facile synthesis of PBNT-BDD. When blended with a nonfullerene acceptor Y6-BO, PBNT-BDD afforded a power conversion efficiency (PCE) of 16.1 % in an OSC, comparable to the benzo[1,2-b:4,5-b′]dithiophene (BDT)-based counterpart. The nonradiative recombination energy loss of 0.19 eV was afforded by PBNT-BDD. PBNT-BDD also exhibited weak crystallinity and appropriate miscibility with Y6-BO, benefitting of morphological stability. The singlet–triplet gap (ΔEST) of PBNT-BDD is as low as 0.15 eV, which is much lower than those of common organic semiconductors (≥0.6 eV). As a result, the triplet state of PBNT-BDD is higher than the charge transfer (CT) state, which would suppress the recombination via triplet state effectively.
Effect of fluorine on optoelectronic properties in DI-A-DII-A-DI type organic molecules: A combined experimental and DFT study
Appalanaidu, Ejjurothu,Busireddy, Manohar Reddy,Chetti, Prabhakar,Vaidya, Jayathirtha Rao,Vidya, V. M.
, (2020/03/17)
The impact of the substitution of fluorine atom/atoms on the optoelectronic features of organic molecules having DI-A-DII-A-DI type architecture is examined in the current work. The three synthesized organic molecules (SMD1, SMD2 and SMD3) comprise of a dithienopyrrole (DTP) derivative as a central donor (DII), which is flanked between two benzothiadiazole (BT) moieties (electron acceptors, A). The BT core on each of two ends is joined to an electron-donating benzodithiophene (BDT) derivative (DI). The SMD1, SMD2 and SMD3 are substituted with 0, 2 and 4 fluorine atoms on their BT moiety respectively. The assistance of DFT methods is taken to evaluate the influence of fluorine on reorganization energies, ionizing potential and electron affinity of molecules. The thermal stability of molecules is mapped by TGA studies. Cyclic voltammetry studies are carried out to comprehend the characteristics of highest molecular orbital, lowest unoccupied molecular orbital and the bandgap of molecules, which are also supported by DFT methods. The molecules displayed better absorption properties in the near-infrared (NIR) region, excellent solution processability in a variety of organic solvents, low bandgap and optimum thermal toughness to make them applicable in the construction of OBHJSCs to play the role of donor materials when connected with acceptors like fullerene derivatives.
Regioisomeric BODIPY Benzodithiophene Dyads and Triads with Tunable Red Emission as Ratiometric Temperature and Viscosity Sensors
Aswathy,Sharma, Sushil,Tripathi, Narendra Pratap,Sengupta, Sanchita
, p. 14870 - 14880 (2019/11/13)
Regioisomeric acceptor-donor (AD) molecular rotors (p-AD, m-AD and m-ADA) were synthesized and characterized, wherein dyads p-AD and m-AD, and triad m-ADA contained 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) and benzodithiophene (BDT) as electron-acceptor and electron-donor, respectively. In all the compounds, the donor and acceptor moieties are electronically decoupled by a phenyl spacer, either through a para coupling or through a meta coupling. The dyad counterparts p-AD and m-AD showed distinct photophysical characteristics in which dyad p-AD showed TICT band at ca. 654 nm characterized by a Stokes shift of ca. 150 nm and prominent solvatochromism. However, meta regioisomeric triad m-ADA showed well-defined aggregation in solution. Notably, because of the temperature-tunable and solvent-viscosity-dependent emission, efficient ratiometric temperature sensing with positive and negative temperature coefficients and viscosity sensing was observed for all compounds. Interestingly, the fluorescence of dyad m-AD (in 10/90 v/v THF/water) revealed a near-white light emission with CIE chromaticity coordinates (x, y) of (0.32, 0.29). Furthermore, the fluorescence emission of p-AD in THF at 0 °C also showed a near-white light emission with chromaticity coordinates (x, y) of (0.34, 0.27). Such multifunctional rotors with readily tunable emission in the red region and prominent temperature- and viscosity-sensing abilities are promising for sensing and bioimaging applications.
