ABSTRACT
Flexible Ti metal substrate-based efficient planar-type CH3NH3PbI3 (MAPbI3) organic-inorganic hybrid perovskite solar cells are fabricated by lamination of the flexible Ti metal substrate/dense TiO2 electron-transporting layer formed by anodization/MAPbI3/polytriarylamine and the graphene/polydimethylsiloxane (PDMS) transparent electrode substrate. By adjusting the anodization reaction time of the polished Ti metal substrate and the number of graphene layers in the graphene/PDMS electrode, we can demonstrate the planar-type MAPbI3 flexible solar cells with a power conversion efficiency of 15.0% (mask area = 1 cm2) under 1 sun condition.
ABSTRACT
We report the performance of perovskite solar cells (PSCs) with an electron transport layer (ETL) consisting of a SnO2 thin film obtained by electrochemical deposition. The surface morphology and thickness of the electrodeposited SnO2 films were closely related to electrochemical process conditions, i.e., the applied voltage, bath temperature, and deposition time. We investigated the performance of PSCs based on the SnO2 films. Remarkably, the experimental factors that are closely associated with the photovoltaic performance were strongly affected by the SnO2 ETLs. Finally, to enhance the photovoltaic performance, the surfaces of the SnO2 films were modified slightly by TiCl4 hydrolysis. This process improves charge extraction and suppresses charge recombination.
ABSTRACT
A step towards commercialization of dye-sensitized solar cells (DSSCs) requires more attention to engineering aspects, such as flexibility, the roll to roll fabrication process, the use of cost effective materials, etc. In this aspect, advantages of flexible DSSCs attracted many researchers to contemplate the transparent conducting oxide coated flexible plastic substrates and the thin metallic foils. In this feature article, the pros and cons of these two kinds of substrates are compared. The flexible dye-sensitized solar cells fabricated using metal substrates are briefly discussed. The working electrodes of DSSCs fabricated on various metal substrates, their fabrication methods, the effect of high temperature calcination and drawbacks of back illumination are reviewed in detail. A few reports on the flexible metal substrate based counter electrodes that could be combined with the plastic substrate based working electrodes are also covered at the end.
ABSTRACT
Composites of electrospun poly(ethylene oxide) (PEO) fibers and silver nanoparticles (Ag NPs) were used as a soft template for coating with TiO2 by atomic layer deposition (ALD). Whereas the as-deposited TiO2 layers on PEO fibers and Ag NPs were completely amorphous, the TiO2 layers were transformed into polycrystalline TiO2 nanotubes (NTs) with embedded Ag NPs after calcination. Their plasmonic effect can be controlled by varying the thickness of the dielectric Al2 O3 spacer between Ag NPs and dye molecules by means of the ALD process. Electronic and spectroscopic analyses demonstrated enhanced photocurrent generation and solar-cell performance due to the intense electromagnetic field of the dye resulting from the surface plasmon effect of the Ag NPs.
ABSTRACT
Dye-sensitized solar cells (DSSCs) have been extensively evolved for the past two decades in order to improve their cell performance. From the commercialization point of view, the overall solar to electrical energy conversion efficiency should compete with other solar cells. But, due to structural restrictions of DSSC using the liquid electrolyte and a space requirement between two electrodes, the direct tandem construction of DSSCs by stacking of repeating units is highly limited. In this feature article, important research trials to overcome these barriers and a recent research trend to improve the light harvesting strategies mainly panchromatic engineering, various tandem approaches such as parallel tandem, series tandem, p-n tandem etc., have been briefly reviewed.
ABSTRACT
The tubular-shaped nanostructure of TiO(2) is very interesting, and highly ordered arrays of TiO(2) nanotubes (TNTs) can be easily fabricated by anodization of the Ti substrate in specific electrolytes. Here in this feature article, we review synthesis methods for various TNTs including normal, alloy, and architectural forms such as bamboos, lace, and flowers. Specific nanosize architectures such as bamboo and lace types can be regulated by alternating voltage and further anodizing. In order to extend light response of TNTs to visible solar spectra, various dopings of specific elements have been discussed. The normal and modified TNTs are suggested for applications such as dye sensitized solar cells, water splitting, photocatalytic degradation of pollutants, CO(2) reduction, sensors, energy storage devices including Li ion batteries and supercapacitors, and other applications such as flexible substrate and biomaterials.
ABSTRACT
We demonstrate that the use of poly(vinyl pyrrolidone) (PVP) and acetic acid during the synthesis of TiO(2) nanotubes may result in the synthesis of single-crystal-like anatase TiO(2) with a mainly exposed and chemically active (001) facet. An enhancement in the overall conversion efficiency of dye-sensitized solar cells was observed in a photoanode consisting of TiO(2) single-crystal-like anatase exposed (001) facets.
ABSTRACT
A cost-effective structure for dye-sensitized solar cells (DSSCs) without using transparent conductive oxide (TCO) is reported. Instead of high-cost F/SnO(2) glass (FTO-glass) or woven metal mesh, a Ti foil and a perforation-patterned stainless steel (StSt) foil are introduced as the substrates for a counter-electrode and a photo-electrode, respectively.
ABSTRACT
A novel ionic siloxane hybrid electrolyte was fabricated by thermal polymerization of iodide-oligosiloxane resin. The nanosized iodide-oligosiloxane was synthesized by a simple sol-gel condensation of 3-iodopropyltrimethoxysilane and diphenylsilanediol. It is found that the composition and concentration of the oligosiloxane used in the electrolyte affect the performance of the dye-sensitized solar cells (DSSCs). An optimized DSSC with the hybrid electrolyte using smaller molecular-sized oligosiloxane with a greater amount of iodide groups presented solar to electricity conversion efficiency of 5.2% at 1 sunlight (100 mW cm(-2)), which is comparable to that afforded by a liquid electrolyte.
ABSTRACT
In the present work, we report a simple method of making glass-based dye-sensitized solar cells (DSSCs) with individual free-standing TiO2 nanotube arrays.
