Engineering a Robust Photovoltaic Device with Quantum Dots and Bacteriorhodopsin

Abstract

We present a route toward a radical improvement in solar cell efficiency using resonant energy transfer and sensitization of semiconductor metal oxides with a light-harvesting quantum dot (QD)/bacteriorhodopsin (bR) layer designed by protein engineering. The specific aims of our approach are (1) controlled engineering of highly ordered bR/QD complexes; (2) replacement of the liquid electrolyte by a thin layer of gold; (3) highly oriented deposition of bR/QD complexes on a gold layer; and (4) use of the Forster resonance energy transfer coupling between bR and QDs to achieve an efficient absorbing layer for dye-sensitized solar cells. This proposed approach is based on the unique optical characteristics of QDs, on the photovoltaic properties of bR, and on state-of-the-art nanobioengineering technologies. It permits spatial and optical coupling together with control of hybrid material components on the bionanoscale. This method paves the way to the development of the solid-state photovoltaic device with the efficiency increased to practical levels.

Bio-nano hybrid materials based on bacteriorhodopsin: Potential applications and future strategies

“…The major advantages of the bR include [22][23][24][25]: (1) Various mutants of bR have been reported to be used in bioelectronics as well as the native one [26][27][28][29]. Two classes of bR mutants have been suggested for solar cell application [30]. The first one includes the mutants, such as 3Glu, in which glutamate (Glu) is replaced by glutamine (Gln) [31,32].…”

“…The second group of the mutant bR consists of cysteine (Cys), unlike the native. These mutants have Cys in 3, 36 and 247 positions of amino acid sequence and are able to attach to the gold surface by their sulfhydryl group through covalent bond [30].…”

Ligand-surface interactions and surface oxidation of colloidal PbSe quantum dots revealed by thin-film positron annihilation methods

“…12,13 Clearly, the development of methods to investigate and monitor surfaces of PbSe QDs embedded in a sub-surface layer in such devices is of crucial importance. In this regard, positron annihilation spectroscopy (PAS) offers unique advantages over XAS, OAS and XPS, since it combines a high sensitivity to selectively probe surfaces of nanoparticles [14][15][16] with an established capacity for depth-profiling of films in the range of ~10 nm to a few m. [17][18][19] These unique merits are highly important in studies of photovoltaic devices, where charge carrier separation requires the formation of a p-n junction, 8 and PAS can probe the involved light absorbing and charge separation layers independently.…”

Enhanced photocurrent generation in bacteriorhodopsin based bio-sensitized solar cells using gel electrolyte

“…In general organic based solvents are used as a solvent for dyes, while BR uses water as a solvent which provides an additional advantage of stability and eco friendly nature to the solar cells. In addition, BR functionally tolerates broad range of pH (5-11) [10][11][12][13][14][15]. The first BSSC made with TiO 2 / BR having triiodide electrolyte combination showed short circuit current (J sc ) maximum of 0.38 mA/cm 2 [16].…”