Designing of an artificial light energy converter in the form of short-chain dyad when combined with core-shell gold/silver nanocomposites

- When the dyads adsorbAg-shell surface of Au@Ag nanocomposite, theybecome mostly elongated in the excited state.
- The core material Au upgrades the Ag-shell to form the elongated species from the folded ones
- Interconversion from folded to extendedconformers protects the charge-separated species within the dyad system.
- dyad-core shell system appears to be a better candidate relative to Dyad-Ag (spherical) for light energy converter

UV-vis absorption, steady state and time resolved fluorescence and absorption spectroscopic investigations demonstrate that the short chain dyad MNTMA when combined with gold-silver core-shell (Au@Ag) nanocomposite , forms elongated conformers in the excited state whereas for the dyad - Ag (spherical) system the majority of dyads remains in a folded conformation. In the dyad-core-shell nanocomposite system, energy wasting charge recombination rate slows down primarily due to elongated conformation and thus it may be anticipated that this hybrid nanocomposite system may serve as a better light energy conversion device.

Graphical AbstractCST-Charge-separated stateVariations are observed in the energy wasting charge recombination (CR) rate processes (kCR ~ 1/τip) due to preponderance of one conformer of the dyad MNTMA over another (* denotes the excited species, kISC: intersystem crossing rate) in cases of the dyad in its pristine form and when it combines with spherical Ag nanoparticles and Au@Ag (hybrid core-shell nanocomposites).129