Click Chemistry on NiO Photocathode to Postfunctionalize a Diketopyrrolopyrrole Sensitizer by Naphthalene Diimide Electron Acceptor

Abstract

This study addresses a practical aspect of hybrid dye-sensitized photoelectrochemical cells by exploring a simple method to prepare multicomponent systems. Building on a previously reported methodology based on a copper-free click chemistry dipolar cycloaddition of azide with activated alkyne, a naphthalene diimide (NDI) derivative substituted with two propiolic esters was clicked on a NiO photocathode already coated with a diketopyrrolopyrrole (DPP) dye bearing two azido groups. A detailed photophysical study by transient absorption spectroscopy demonstrates that optical excitation of DPP dye leads to an effective electron transfer chain from the NiO valence band to the NDI passing via the DPP dye, resulting to a long-lived charge-separated state (hole in NiO/NDI radical anion) of 170 s. p-type dye-sensitized solar cells were also fabricated with the above molecular components and confirm the occurrence of the electron transfer as the performances of the solar cells were improved in terms of Voc and Jsc compared to the DPP dye lacking the NDI unit. The above clicked system was also compared to a covalently linked DPP-NDI dyad, whose performances are 30% superior to the clicked system probably due to longer mean distance between the NiO surface and the NDI with the dyad. This finding paves the way for the design of multicomponent hybrid dyesensitized photoelectrochemical cells by chemistry on the electrode.

KuQuinones: a ten years tale of the new pentacyclic quinoid compound

“…Importantly, this is the first example in which a pentacyclic quinoid core has been employed as photoactive species in a p-DSSC. Although both J sc and η % are lower with respect to the “champions” (push–pull dyes and molecular dyads), 43–46 they are in line with other reported sensitizer, 65 such as diketopyrrolopyrrole, 36,58 carbazole, 66–68 phenoxazine, 37 bodipy, 40 squaraines, 69,70 coumarine 41 and isoindigo 71 derivatives (Fig. 10).…”

“…Sensitizers used as photoactive components in p-DSSC can be divided into metal complexes 34 and metal free organic dyes. [35][36][37][38][39][40][41][42] Among the latter, push-pull molecules (donor-pspacer-acceptor), [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] and molecular dyads (donor-acceptor) [58][59][60][61][62][63] gave the best results in terms of generated photocurrent. In the framework of the on-going research of new sensitizers, KuQ have been tested in p-DSSCs.…”

Clicking in harmony: exploring the bio-orthogonal overlap in click chemistry

“…30. 170 Jong Lee and his group worked on the adhering epidermal growth factor (EGF) onto the surface of collagen, boosting proliferation and anchoring factors of the corneal epithelial cells. They proceeded by attaching the azido group over the surface of EDF and covalently coupling it with the DBCO group present on the collagen surface through SPAAC (as depicted in the Fig.…”

Photoelectrochemical Hydrogen Production by a Cobalt Tetrapyridyl Catalyst Using Push–Pull Dye‐Sensitized NiO Photocathodes

“…In addition, DS-PECs can also benefit from recent successes in bioinspired catalysis for energy-relevant applications to find alternatives to platinum group metal catalysts [8] and, today, several examples of H 2 -evolving photocathodes assembling molecular first row transition metal-based catalytic centers with push-pull organic dyes have been described in the literature. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] However, up to now, the photoelectrochemical performances of these fully earth abundant systems remain relatively low. Strategies that would allow accelerating the screening and selection of promising dye and catalyst structures while providing structure-property relationships are thus highly needed to advance this field of research.…”