273-13-2Relevant articles and documents
The improvement of photovoltaic performance of quinoline-based dye-sensitized solar cells by modification of the auxiliary acceptors
?i?man, ?lkay,Arkan, Burcu,Arslan, Bar?? Se?kin,Avc?, Davut,Derin, Yavuz,Gezgin, Merve,Nebio?lu, Mehmet,Tutar, Ahmet
, (2020/10/07)
Three new dyes containing diphenylamine as electron donor, benzene (BIM1), benzothiadiazole (BTD) (BIM2) and N-ethylhexylbenzotriazole (BTZ) (BIM3) as auxiliary electron acceptors, quinoline as π-bridge and cyanoacrylic acid as anchoring group were synthesized in D-A-π-A structure for use in dye-sensitized solar cells (DSSCs). The optical, electrochemical, theoretical and photovoltaic methods were performed to understand the auxiliary acceptor influence on the performance of these dyes. Compared to the other dyes, the DSSC with dye BIM3 slightly increases the open circuit voltage (Voc) owing to the retardation of charge recombination by BTZ. However, replacement of benzene or BTZ by BTD unit causes a large red shift of the absorption spectra, leading BIM2 cell to produce the highest short circuit current density (Jsc). Thus, among the three D-A-π-A dyes, BIM2 is determined to be the most efficient dye, which reached a Voc of 0.627 V and Jsc of 11.53 mA cm–2, corresponding to an overall power conversion efficiency of 5.21 % in the presence of chenodeoxycholic acid (CDCA) as the coadsorbent. These results suggest that the insertion of benzothiadiazole as auxiliary acceptor into quinoline-based D-A-π-A dyes can effectively improve photovoltaic performance of DSSCs.
Fluorescence emission enhancement of a T-shaped benzimidazole with a mechanically-interlocked ‘suit’
Xu, Houyang,Lin, Meng-Di,Yuan, Jun,Zhou, Baiyang,Mu, Yingxiao,Huo, Yanping,Zhu, Kelong
supporting information, p. 3239 - 3242 (2021/04/06)
A fluorescent T-shaped benzimidazole was successfully designed and interlocked in a bicyclic macrocycle to form a suit[1]ane through supramolecular templated-synthesis. Compared with the bare fluorophore, suit[1]ane requires nearly two times the concentration to initialize the aggregation-caused quenching effect in solution. Furthermore, an 8-fold higher solid-state fluorescence quantum yield (21.7%) is also achieved. By taking advantage of mechanical bonding and molecular packing, such fluorescence emission enhancement through formation of a suitane opens the way to new complex fluorescent materials.
Between Aromatic and Quinoid Structure: A Symmetrical UV to Vis/NIR Benzothiadiazole Redox Switch
Rietsch, Philipp,Sobottka, Sebastian,Hoffmann, Katrin,Popov, Alexey A.,Hildebrandt, Pascal,Sarkar, Biprajit,Resch-Genger, Ute,Eigler, Siegfried
, p. 17361 - 17365 (2020/12/01)
Reversibly switching the light absorption of organic molecules by redox processes is of interest for applications in sensors, light harvesting, smart materials, and medical diagnostics. This work presents a symmetrical benzothiadiazole (BTD) derivative with a high fluorescence quantum yield in solution and in the crystalline state and shows by spectroelectrochemical analysis that reversible switching of UV absorption in the neutral state, to broadband Vis/NIR absorption in the 1st oxidized state, to sharp band Vis absorption in the 2nd oxidized state, is possible. For the one-electron oxidized species, formation of a delocalized radical is confirmed by electron paramagnetic resonance spectroelectrochemistry. Furthermore, our results reveal an increasing quinoidal distortion upon the 1st and 2nd oxidation, which can be used as the leitmotif for the development of BTD based redox switches.
