Linker-Free Deposition and Adhesion of Photosystem I onto Nanostructured TiO₂ for Biohybrid Photoelectrochemical Cells

Abstract

Photosystem I (PSI) from oxygenic photosynthetic organisms is an attractive sensitizer for nano-biohybrid solar cells as it has a combined light-harvesting and reaction center in one protein complex and operates at a quantum yield close to one in biological systems. Using a linker-free deposition technique enabled by an electrospray system, PSI was coupled to 1-D nanostructured titanium dioxide thin films to fabricate an electrode for a photoelectrochemical cell. After deposition, the surfactant in the PSI aggregate was dissolved in the surfactant-free electrolyte, ensuring that partly hydrophobic PSI was not resuspended and stayed in contact with titanium dioxide. A maximum current density of 4.15 mA cm(-2) was measured after 10 min of electrospray deposition, and this is the highest current density reported so far for PSI-based photoelectrochemical cells. The high current is attributed to 1D nanostructure of titanium dioxide and orientation of the PSI onto the surface, which allows easy transfer of electrons.

Crumpled graphene oxide decorated SnO2 nanocolumns for the electrochemical detection of free chlorine

“…1). The electrospray technique has been described and used previously to selfassemble molecules and deposit on metal oxide thin films (Shah et al 2015;Kavadiya et al 2016). Moreover, electrospray can be used to crumple GO sheets via evaporation induced crumpling.…”

“…Aerosol-based synthesis routes are advantageous due to their scalability and low cost while still maintaining precise control and flexibility in deposition (Pratsinis 2010;Jiang et al 2016Jiang et al , 2017. For electrode fabrication, SnO 2 -nanostructured columns were produced using ACVD and functionalized with crumpled graphene oxide (CGO) using electrospray deposition (Shah et al 2015). The main advantage of these aerosol-based techniques is the single step synthesis and deposition of the material on the substrate in the desired morphology (Zhan et al 2010).…”

Photovoltaic activity of electrodes based on intact photosystem I electrodeposited on bare conducting glass

“…What differs various PSI-containing photoelectrodes described in the literature is: (1) the substrate on which PSI is deposited, (2) the method of PSI immobilization on the substrate, (3) the way by which the electric contact between PSI and the substrate as well as between PSI and the counter electrode is achieved, (4) the species from which the PSI is extracted and the type of the PSI preparation. The electrode substrates used for PSI immobilization are gold (Ciesielski et al 2008(Ciesielski et al , 2010aMukherjee et al 2010;Stieger et al 2016a), graphene (Gunther et al 2013;Feifel et al 2015), titanium dioxide (Mershin et al 2012;Gordiichuk et al 2014;Shah et al 2015;Yu et al 2015;Gizzie et al 2015), or a conducting glass, FTO or ITO (Indium-doped Tin Oxide) (Ocakoglu et al 2014;Stieger et al 2016b;Szewczyk et al 2017Szewczyk et al , 2018. The substrate may have a flat surface or a porous structure to increase the number of attached proteins and thus to maximize the photocurrent.…”

Biohybrid Photoprotein‐Semiconductor Cells with Deep‐Lying Redox Shuttles Achieve a 0.7 V Photovoltage

“…One option that exploits naturally available materials is to use light harvesting and photovoltaic pigment‐proteins from photosynthetic organisms as components in biohybrid photoelectrochemical cells . Most of the progress in this area has been made with the Photosystem I complex from oxygenic phototrophs and the reaction center (RC) from the anoxygenic photosynthetic bacterium Rhodobacter ( Rba .) sphaeroides .…”