Data‐driven materials discovery has become increasingly important in identifying materials that exhibit specific, desirable properties from a vast chemical search space. Synergic prediction and experimental validation are needed to accelerate scientific advances related to critical societal applications. A design‐to‐device study that uses high‐throughput screens with algorithmic encodings of structure–property relationships is reported to identify new materials with panchromatic optical absorption, whose photovoltaic device applications are then experimentally verified. The data‐mining methods source 9431 dye candidates, which are auto‐generated from the literature using a custom text‐mining tool. These candidates are sifted via a data‐mining workflow that is tailored to identify optimal combinations of organic dyes that have complementary optical absorption properties such that they can harvest all available sunlight when acting as co‐sensitizers for dye‐sensitized solar cells (DSSCs). Six promising dye combinations are shortlisted for device testing, whereupon one dye combination yields co‐sensitized DSSCs with power conversion efficiencies comparable to those of the high‐performance, organometallic dye, N719. These results demonstrate how data‐driven molecular engineering can accelerate materials discovery for panchromatic photovoltaic or other applications.

Three benzimidazole-based isomeric organic dyes possessing two triphenylamine donors and a cyanoacrylic acid acceptor are prepared by stoichiometrically controlled Stille or Suzuki-Miyaura coupling reaction which predominantly occurs on the N-butyl side of benzimidazole due to electronic preferences. Combined with the steric effect of the N-butyl substituent, placement of the acceptor segment at various nuclear positions of benzimidazole such as C2, C4, and C7 led to remarkable variations in intramolecular charge transfer absorption, electron injection efficiency, and charge recombination kinetics. The substitution of acceptor on the C4 led to red-shifted absorption, while that on C7 retarded the charge transfer due to twisting in the structure caused by the butyl group. Because of the cross-conjugation nature and poor electronic interaction between the donor and acceptor, the dye containing triphenylamine units on C4 and C7 and the acceptor unit on C2 showed the low oxidation potential. Thus, this dye possesses favorable HOMO and LUMO energy levels to render efficient sensitizing action in solar cells. Consequently, it results in high power conversion efficiency (5.01%) in the series with high photocurrent density and open circuit voltage. The high photocurrent generation by this dye is reasoned to it exceptional charge collection efficiency as determined from the electron impedance spectroscopy.

Three new isomeric naphthalimide conjugated porphyrins are developed for photocatalytic H2 production. The para-substituted isomer, ZnT(p-NI)PP delivers the highest rate (ηH2) of 973 μmol g−1 h−1 due to the efficient intramolecular energy transfer from the naphthalimide to the porphyrin core.

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New perylenediimide-porphyrin acceptors, 4PDI-ZnP and 2PDI-ZnP, have been facilely synthesized by acid-catalyzed condensation of perylenediimide-substituted benzaldehyde with pyrrole and dipyrromethane, respectively, and subsequent Zn(ii)-complexation.

A linear 5,15-di(naphthalimide) substituted porphyrin ZnD(p-NI)PP is facilely self-assembled into nanowires in solid with well-defined morphology through the synergistic π−π stack interactions of both porphyrin and naphthalimide skeletons. The self-assembled porphyrin nanowires feature broadened light absorption, efficient separation and transfer of photogenerated charges, and enhanced photostability. As a consequence, the ZnD(p-NI)PP produced 108 times higher H 2 production rate (ηH 2 = 5.40 mmol g −1 h −1 ) than the control 5,15-diphenylporphyrin (ZnDPP) (ηH 2 = 0.05 mmol g −1 h −1 ) and 3.6-fold higher than the ZnT(p-NI)PP (ηH 2 = 1.50 mmol g −1 h −1 ) which bears four NI units and self-assembled into nanospheres in the solid. Additionally, the photocatalytic system of ZnD(p-NI)PP produced hydrogen evolution up to 50 h, while the hydrogen evolution of the ZnDPP photocatalytic system reached a plateau after 20 h.

A simple heteroleptic iridium­(III) photosensitizer, Ir-1, containing two ligands 5-(trifluoromethyl)-2-phenylpyridine (ĈN–CF3) and bipyridine (N̂N) has for the first time been studied for cocatalyst-free photocatalytic hydrogen evolution (PHE). The complex Ir-1 produces a hydrogen production rate (ηH2) of 3.2 mmol g–1 h–1, which is over 3.6-fold higher than that of the control complex Ir-2 (0.9 mmol g–1 h–1) containing bipyridine and 2-phenylpyridine ligands without CF3 groups. The higher ηH2 of Ir-1 could be ascribed to the high light-harvesting property, longer triplet electron lifetime, and more appropriate driving force for accepting electrons from the sacrificial donor, which enable efficient charge separation and transfer of electrons for hydrogen evolution. Additionally, the photostability issues of Ir-1 and Ir-2 are addressed by the selection of suitable organic solvent/water photocatalytic systems.

A T-Ir complex was conjugated to a porphyrin ring via a phenylene linkage to afford a new ZnP-T-Ir photosensitizer which exhibits aggregation induced emission (AIE) for the T-Ir unit, an...