Resonance energy transfer from PbS colloidal quantum dots to bulk silicon: the road to hybrid photovoltaics

Spectroscopic evidence of resonance energy transfer mechanism from PbS QDs to bulk silicon

“…4. The PL decay rate increases significantly for SiO 2 spacer thicknesses below 12 nm [14]. It remains almost constant for SiO 2 spacer thicknesses greater than 12 nm, with values comparable to the decay rate of PbS QDs deposited on a glass substrate.…”

“…For spacer thickness greater than 12 nm, there is no net absorption of energy by the silicon and the decay rate of the PbS QDs is found to be almost equal to the value on glass [14]. For separation distances below 12 nm, the lifetime is sharply reduced due to the gradual opening of the transfer channel to silicon.…”

“…It remains almost constant for SiO 2 spacer thicknesses greater than 12 nm, with values comparable to the decay rate of PbS QDs deposited on a glass substrate. The observed acceleration in the lifetimes of PbS QDs for short separation distances is a strong evidence of RET from the QDs to the bulk silicon [14].…”

“…2. -Schematic description of the RET mechanism from oleic-acid-capped PbS QDs to a bulk silicon substrate, through a SiO2 spacing layer [14].…”

Local field effects for spherical quantum dot emitters in the proximity of a planar dielectric interface

“…Their compositionand size-dependent energy gaps allow for easy tuning of the emission wavelength, and the continuing progress in the chemical processing results in high and stable luminescent quantum efficiencies. In one of the recent application targets, colloidal QDs are utilized [3][4][5][6][7][8][9][10][11][12] in energy transfer (ET)-based hybrid nanostructures [13] in the role of primary light absorbers to further sensitize adjacent semiconductor substrates/ structures for prospective photovoltaic devices. This excitonic (by means of ET) sensitization [14] is particularly appealing for crystalline silicon substrates as it would eliminate the weak solar light absorption in the indirect bandgap Si as a defining design factor, thus possibly leading to ultrathin silicon devices.…”