Preparation and application of a D–A conjugated electrochromic flexible electrode with side chain carbazole active groups in supercapacitors

Electrochromic power storage devices (ESCs) integrate energy storage and electrochromic behaviour into a single full cell that can enable the visualization of the energy status by the naked eye.

Developments of Diketopyrrolopyrrole-Dye-Based Organic Semiconductors for a Wide Range of Applications in Electronics

In recent times, fused aromatic diketopyrrolopyrrole (DPP)-based functional semiconductors have attracted considerable attention in the developing field of organic electronics. Over the past few years, DPP-based semiconductors have demonstrated remarkable improvements in the performance of both organic field-effect transistor (OFET) and organic photovoltaic (OPV) devices due to the favorable features of the DPP unit, such as excellent planarity and better electron-withdrawing ability. Driven by this success, DPP-based materials are now being exploited in various other electronic devices including complementary circuits, memory devices, chemical sensors, photodetectors, perovskite solar cells, organic light-emitting diodes, and more. Recent developments in the use of DPP-based materials for a wide range of electronic devices are summarized, focusing on OFET, OPV, and newly developed devices with a discussion of device performance in terms of molecular engineering. Useful guidance for the design of future DPP-based materials and the exploration of more advanced applications is provided.

Synthesis of 2,5-Dibutyl-3,6-dimethyl-1 H,2 H,4 H,5 H-pyrrolo[3,4- c]pyrrole-1,4-dione: A Diketopyrrolopyrrole Scaffold for the Formation of Alkenyldiketopyrrolopyrrole Compounds

This manuscript describes an unprecedented and efficient synthesis of a new DPP scaffold, 2,5-dibutyl-3,6-dimethyl-1 H,2 H,4 H,5 H-pyrrolo[3,4- c]pyrrole-1,4-dione (DMDPP), containing methyl groups at the 3,6-positions as a precursor to preparing 3,6-divinyl-substituted DPP compounds. Subsequently, following the synthesis of DMDPP, we performed an efficient and mild C-H functionalization of the methyl groups with a variety of aromatic aldehydes to synthesize the first examples of 3,6-divinyl-substituted DPP compounds in moderate to good yields.

Solar H2 evolution in water with modified diketopyrrolopyrrole dyes immobilised on molecular Co and Ni catalyst-TiO2 hybrids

A series of diketopyrrolopyrrole (DPP) dyes with a terminal phosphonic acid group for attachment to metal oxide surfaces were synthesised and the effect of side chain modification on their properties investigated.

A series of diketopyrrolopyrrole (DPP) dyes with a terminal phosphonic acid group for attachment to metal oxide surfaces were synthesised and the effect of side chain modification on their properties investigated. The organic photosensitisers feature strong visible light absorption (λ = 400 to 575 nm) and electrochemical and fluorescence studies revealed that the excited state of all dyes provides sufficient driving force for electron injection into the TiO₂ conduction band. The performance of the DPP chromophores attached to TiO₂ nanoparticles for photocatalytic H₂ evolution with co-immobilised molecular Co and Ni catalysts was subsequently studied, resulting in solar fuel generation with a dye-sensitised semiconductor nanoparticle system suspended in water without precious metal components. The performance of the DPP dyes in photocatalysis did not only depend on electronic parameters, but also on properties of the side chain such as polarity, steric hinderance and hydrophobicity as well as the specific experimental conditions and the nature of the sacrificial electron donor. In an aqueous pH 4.5 ascorbic acid solution with a phosphonated DuBois-type Ni catalyst, a DPP-based turnover number (TON_DPP) of up to 205 was obtained during UV-free simulated solar light irradiation (100 mW cm^–2, AM 1.5G, λ > 420 nm) after 1 day. DPP-sensitised TiO₂ nanoparticles were also successfully used in combination with a hydrogenase or platinum instead of the synthetic H₂ evolution catalysts and the platinum-based system achieved a TON_DPP of up to 2660, which significantly outperforms an analogous system using a phosphonated Ru tris(bipyridine) dye (TON_Ru = 431). Finally, transient absorption spectroscopy was performed to study interfacial recombination and dye regeneration kinetics revealing that the different performances of the DPP dyes are most likely dictated by the different regeneration efficiencies of the oxidised chromophores.

A supramolecular assembly of metal-free organic dye with zinc porphyrin chromophore for dye-sensitized solar cells

The supramolecular system has superior performance in improving spectral response and reducing charge recombination, which could be a promising and convenient method to improve the performance of DSSCs.

All-solid-state nanocomposite electrolytes composed of an ionic polymer with polar groups and surface-modified SiO2 nanoparticles for dye-sensitized solar cells

Polar groups on modified SiO₂ facilitate the ionization of DMPII and enhance the efficiency of DSCs.

New D–D–π–A type organic dyes having carbazol-N-yl phenothiazine moiety as a donor (D–D) unit for efficient dye-sensitized solar cells: experimental and theoretical studies

DSSCs using novel organic dyes (CPhTnPA, n = 0–2) with carbazol-N-yl phenothiazine moiety as a donor (D–D) unit as the sensitizers exhibited efficiency as high as 7.78% which reached 95% with respect to that of the reference N719-based device (8.20%).