Synthesis of new N, N-diphenylhydrazone dyes for solar cells: Effects of thiophene-derived π-conjugated bridge

Effect of Molecular-Level Insulation on the Performance of a Dye-Sensitized Solar Cell: Fluorescence Studies in Solid State

“…To promote efficient charge injection (k 1 ) and dye regeneration (k 2 ) in the DSSC, the LUMO must remain sufficiently higher than the edge of the conduction band of TiO 2 for efficient charge injection while the HOMO must remain sufficiently below the redox level of the HTM for efficient regeneration of the dye ( Figure S11) [42,43]. The theoretical results here demonstrated that such energy lying was not significantly alerted in the presence of the macrocyclic β-CD host, with the energy of the HOMO changing by +0.04 to −0.07 eV and energy of the LUMO changing by −0.13 to −0.28 eV in the optimized structures for inclusion complexes, leading to a small increase the Voc of encapsulated dye solar cells from 0.7 to 0.8 V ( Table 3).…”

Zinc–Porphyrin Dyes with Different meso‐Aryl Substituents for Dye‐Sensitized Solar Cells: Experimental and Theoretical Studies

“…[27,30] By using the bidentate binding mode of the carboxyl group ( À COOH) on a TiO 2 anatase (101) surface, the two TiÀO bonds of the zinc-porphyrin-(TiO 2 ) 38 complexes were found to be 2.16 with the calculated adsorption energy (E ads ) of À12.79-À13.14 kcal mol À1 (see the Supporting Information), thus indicating strong chemical binding. The HOMO and LUMO orbitals of ZnPPA À A C H T U N G T R E N N U N G (TiO 2 ) 38 and ZnPCPA À A C H T U N G T R E N N U N G (TiO 2 ) 38 complexes are illustrated in Figure 7. The electron distributions in the HOMO orbital of the ZnPPAÀA C H T U N G T R E N N U N G (TiO 2 ) 38 complex are mainly localized on the porphyrin core, whereas in the HOMO of the ZnPCPAÀA C H T U N G T R E N N U N G (TiO 2 ) 38 complex, they are localized on both the porphyrin core and carbazole phenyl substituents.…”

“…Moreover, within the present series of dyes, the charge-transfer effects were expected to be enhanced for ZnPCPA and ZnPCTA (which bear three carbazole aryl substituents) relative to ZnPPA. To confirm the efficient electron injection from the porphyrin excited state into the CB of TiO 2 in the device, the prototype system was modeled by dyes ZnPPA and ZnPCPA adsorbed onto the (TiO 2 ) 38 cluster. The optimizations were carried out by means of the Perdew-Burke-Ernzerhof (PBE)/double-numeric polarized (DNP) method implemented in the DMol 3 program.…”

“…[38] The charge-recombination resistance (R CT ) at the TiO 2 surface can be deduced by fitting curves from the middle-frequency range using ZMAN software ( Figure 10c and Table 2). The value of R CT is related to the charge-recombination rate between the injected electron and electron acceptor I 3 À in the electrolyte, estimated by radius of the larger semicircle.…”

Organic dyes containing a hydrazone moiety as auxiliary donor for solid-state DSSC applications

“…Squaraine-based compounds possessing a hydrazone moiety were synthesized and applied as efficient small molecule donors in bulkheterojunction solar cells [25]. Ping Shen et al designed and synthesized a series of the hydrazone dyes possessing N,N-diphenylhydrazone donor and 2-cyanoacetic acid acceptor linked by a different aromatic bridge [26,27], while we have incorporated this fragment between the donor and acceptor parts thus designing a novel D-π-A type of organic dyes for ssDSSCs [28][29][30].…”