New Diketopyrrolopyrrole (DPP) Dyes for Efficient Dye-Sensitized Solar Cells

Abstract

Two novel metal-free dyes (DPP-I and DPP-II) with a diketopyrrolopyrrole (DPP) core were synthesized for dye-sensitized solar cells (DSSCs). The absorption spectra and electrochemical and photovoltaic properties of DPP-I and DPP-II were extensively investigated. Electrochemical measurement data indicate that the tuning of the HOMO and LUMO energy levels can be conveniently accomplished by alternating the π-conjugated systems. Besides, coadsorption of chenodeoxycholic acid (CDCA) can hinder the formation of dye aggregates and might improve electron injection yield and, thus, J sc. This has also led to a rise in the photovoltage, which is attributed to the decrease of charge recombination. The DSSC based on dye DPP-I showed better photovoltaic performance: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 80%, a short-circuit photocurrent density (J sc) of 9.78 mA cm−2, an open-circuit photovoltage (V oc) of 605 mV, and a fill factor (FF) of 0.69, corresponding to an overall conversion efficiency of 4.14% under standard global AM 1.5 solar light condition. This work suggests that the metal-free dyes based on a DPP core are promising candidates for improvement of the performance of DSSCs.

Diketopyrrolopyrroles: Synthesis, Reactivity, and Optical Properties

“…The fi rst examples of such applications of DPPs were reported by Tian, Hua, and co-workers in 2010. [ 111 ] They synthesized an asymmetrical donor-acceptor-acceptortype DPP dye 176a bearing a donating bis(4-methoxyphenyl)amino group and carboxycyanoethenyl-substituted thiophene as the electron-accepting unit ( Scheme 62 ). For a DSSC device employing dye 176a as the sensitizer, an overall energy conversion effi ciency ( η ) of 4.14% was obtained.…”

Torsional angle dependence and switching of inner sphere reorganisation energies for electron and hole transfer processes involving phenyl substituted diketopyrrolopyrroles; a density functional study

“…[14][15][16][17][18][19][20][21] We have recently undertaken a detailed characterisation of the photophysical, photochemical and charge transfer, CT properties of single molecule DPPs in solution, the solid phase and in thin films with a view to ultimately developing novel sensor applications and electronic devices.…”

“…To the best of our knowledge there are no published values of λ h/e hitherto for any DPPs despite the ever-growing number of publications involving their use in CT based materials. [9][10][11][12][13][14][15][16][17][18][19][20] The rest of the paper is laid out as follows; first, we give a brief description of the computation methods used to determine λ h/e (according to Equations 2-4). In the results and discussion section we first describe the influence of basis set and DFT employed on the computed λ h/e values of H 2 P 2 DPP.…”

Investigation of Optical Properties of Solochrome Dark Blue Dye Doped Polymer Films

“…Nonlinear optical materials have received much interest because of their potential applications in optical devices such as, light emitting diodes, solar cells, optical sensors, optical signal processing, optical switching, optical power limiting, and optoelectronic devices [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. The optical and electrical properties of wide range of materials, including organic and inorganic materials, semiconductors, and polymer materials, have been studied to develop practical optical devices [16][17][18][19][20][21][22][23].…”