One-pot hydrothermal synthesis of TiO2/graphene nanocomposites for enhanced visible light photocatalysis and photovoltaics

Abstract

Two dimensional (2D) nanostructures such as graphene have been attracting increasing research interest in the recent past due to their superior material properties. Herein, we report a facile and scalable method for the production of a few layered graphene sheets and the synthesis of TiO 2 nanoparticles on the surface of the prepared graphene sheets using a single step hydrothermal method. The composites prepared with different graphene loading were assessed for their photocatalytic degradation ability under visible light and in dye sensitized solar cells (DSC). The results showed that the average thickness of the obtained graphene sheets was 1.1 nm and the TiO 2 nanoparticles were uniformly dispersed on the surface of the graphene. In the photodegradation of methyl orange (MO), the photoactivity of the composite (with 10 wt% graphene loading) was found to be three times better than bare TiO 2 nanoparticles. This increased activity is due to the synergistic effects of TiO 2 nanoparticles and graphene sheets. For DSC, composites with 0.7 wt% graphene loading showed a maximum efficiency of 4.26%, 25% higher than without graphene.

Graphene below the percolation threshold in TiO2for dye-sensitized solar cells

“…[25][26][27][28][29][30][31] Another recently exploited strategy relies on the addition of tin oxide nanosheets to TiO 2 anatase nanopowder, 32 featuring quite a high PCE (8.25%).…”

Plasmon Enhanced Photovoltaic Performance in TiO2-Graphene Oxide Composite Based Dye-Sensitized Solar Cells

“…This enhanced overall photoresponse clearly suggests the improved charge injection and charge transfer by means of reducing recombination rates and possibly due to tiny bandgap narrowing into DSSC operation. 25,26 It has also been reported that modifying photo-anode with graphene oxide increases dye adsorption into it. So the higher surface area could also advance a rise in J SC .…”

“…Moreover, addition of GO to TiO 2 could also extend the photoresponse into visible region because of its tunable energy gap depending on the oxidation degree and structural distortion. [25][26][27] Thus, plasmon enhanced photovoltaic performance of DSSC can be further improved and stabilized by adding GO as it can * Electrochemical Society Student Member.…”

“…Moreover, addition of GO to TiO 2 could also extend the photoresponse into visible region because of its tunable energy gap depending on the oxidation degree and structural distortion. [25][26][27] Thus, plasmon enhanced photovoltaic performance of DSSC can be further improved and stabilized by adding GO as it can * Electrochemical Society Student Member.* * Electrochemical Society Active Member. z E-mail: agg.radhe@gmail.com increase the charge collection by visible light driven photosensitization, charge transfer and collection by quenching brisk recombination and thus fastening electron transport into semiconductor titania.…”

Graphene-based hollow TiO2 composites with enhanced photocatalytic activity for removal of pollutants

“…Graphene, single atomic layer, two-dimensional graphitic carbon material, is suitable for utilize as the photocatalyst support material due to its unique properties, such as excellent electrical conductivity, high chemical stability, large specific surface area, and unique electronic and mechanical properties, flexible structure [10][11][12]. Because of its remarkable properties, there is interest in using graphene for various applications such as catalytic activity, photovoltaics, supercapacitors, energy storage nano electronics, lithium-ion batteries [13,14].…”