Publications by authors named "Shuvasree Ray"

Multichromophoric dye-sensitized solar cells (DSSCs) comprised of a supramolecular zinc-phthalocyanineperyleneimide (ZnPc···PMI) dyad convert light to electrical energy with much higher power conversion efficiency (PCE = 2.3%) and incident-photon-to-current-efficiency (IPCE = ca. 40%) than the devices made of individual dyes.

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Over the past decade anion-π interaction has emerged as a new paradigm of supramolecular chemistry of anions. Taking advantage of the electronic nature of anion-π interaction, we have expanded its boundaries to charge-transfer (CT) and formal electron transfer (ET) events by adjusting the electron-donating and accepting abilities of anions and π-acids, respectively. To establish that ET, CT, and anion-π interactions could take place between different anions and π-acids as long as their electronic and structural properties are conducive, herein, we introduce 3,4,9,10-perylenediimide (PDI-1) that selectively undergoes thermal ET from strong Lewis basic hydroxide and fluoride anions, but remains electronically and optically silent to poor Lewis basic anions, as ET and CT events are turned OFF.

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Multichromophoric dye-sensitized solar cells (DSCs) based on self-assembled zinc-porphyrin···peryleneimide dyads on TiO(2) films display more efficient light-to-electrical energy conversion than DSCs based on individual dyes. Higher efficiency of multichromophoric dyes can be attributed to co-sensitization as well as vectorial electron transfer that lead to better electron-hole separation in the device.

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We designed and synthesized three compounds incorporating a BODIPY fluorophore and an oxazine photochrome within the same molecular skeleton and differing in the nature of the linker bridging the two functional components. The [1,3]oxazine ring of the photochrome opens in less than 6 ns upon laser excitation in two of the three fluorophore-photochrome dyads. This process generates a 3H-indolium cation with a quantum yield of 0.

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