A5013586723- Perovskite Materials and Applications
- Conducting polymers and applications
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- TiO2 Photocatalysis and Solar Cells
- Advanced Photocatalysis Techniques
- Solid-state spectroscopy and crystallography
- Silicon Nanostructures and Photoluminescence
- High-pressure geophysics and materials
- Laser-Matter Interactions and Applications
- Thin-Film Transistor Technologies
- Laser-Plasma Interactions and Diagnostics
- Semiconductor materials and devices
- Ga2O3 and related materials
- Semiconductor Quantum Structures and Devices
- Analytical Chemistry and Sensors
Stanford University
2012-2017
Stanford Medicine
2014
Texas A&M University
2012
This report discusses slow transient and hysteretic phenomena in perovskite-absorber solar cells.
Semi-transparent perovskite solar cells with silver nanowires are stacked on CIGS and Si to achieve solid-state polycrystalline tandems efficiency improvement.
2,2',7,7'-Tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD), the prevalent organic hole transport material used in solid-state dye-sensitized solar cells and perovskite-absorber cells, relies on an uncontrolled oxidative process to reach appreciable conductivity. This work presents use of a dicationic salt spiro-OMeTAD, named spiro(TFSI)2, as facile means controllably increasing conductivity spiro-OMeTAD up 10(-3) S cm(-1) without relying oxidation air. Spiro(TFSI)2...
With the advent of efficient high-bandgap metal-halide perovskite photovoltaics, an opportunity exists to make perovskite/silicon tandem solar cells. We fabricate a monolithic by developing silicon-based interband tunnel junction that facilitates majority-carrier charge recombination between and silicon sub-cells. demonstrate 1 cm2 2-terminal multijunction cell with VOC as high 1.65 V. achieve stable 13.7% power conversion efficiency current-limiting sub-cell, identify key challenges for...
A sputtered oxide layer enabled by a solution-processed nanoparticle buffer to protect underlying layers is used make semi-transparent perovskite solar cells. Single-junction cells are 12.3% efficient, and mechanically stacked tandems on silicon 18.0% efficient. The cell has T 80 lifetime of 124 h when operated at the maximum power point 100 °C without additional sealing in ambient atmosphere under visible illumination. As service our authors readers, this journal provides supporting...
Low-cost solar technologies such as perovskite cells are not only required to be efficient, but durable too, exhibiting chemical, thermal and mechanical stability. To determine the stability of cells, fracture resistance a multitude solution-processed organometal trihalide films utilizing these were studied. The influence stoichiometry, precursor chemistry, deposition techniques, processing conditions on layers was investigated. In all cases, perovskites offered negligible fracture, failing...
Despite the promise of quantum dots (QDs) as a light-absorbing material to replace dye in dye-sensitized solar cells, dot-sensitized cell (QDSSC) efficiencies remain low, due part high rates recombination. In this article, we demonstrate that ultrathin recombination barrier layers Al2O3 deposited by atomic layer deposition can improve performance cadmium sulfide (CdS) cells with spiro-OMeTAD solid-state hole transport material. We explored depositing either before or after QDs, resulting...
Transparent top electrodes for solid‐state dye‐sensitized solar cells (ssDSCs) allow fabrication of mechanically stacked ssDSC tandems, partially transparent ssDSCs building integration, and on metal foil substrates. A solution‐processed, highly transparent, conductive electrode based PEDOT:PSS [poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate)] spray‐deposited silver nanowires (Ag NWs) is developed as an effective contact ssDSCs. The solution‐deposited using conditions solvents that...
A method for achieving complete pore-filling in solid-state dye-sensitized solar cells termed melt-infiltration is presented: after the customary solution-processed deposition of spiro-OMeTAD, device heated above glass transition temperature spiro-OMeTAD to soften material and allow capillary action pull additional from overlayer reservoir into pores. The fraction increases 60–65% 90–100% as a result melt-infiltration. organic D–π–A dye used this study found withstand thermal treatment...
A major limitation of solid-state dye-sensitized solar cells is a short electron diffusion length, which due to fast recombination between electrons in the TiO2 electron-transporting layer and holes 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene (Spiro-OMeTAD) hole-transporting layer. In this report, sensitizing dye that separates from Spiro-OMeTAD was engineered slow increase device performance. Through synthesis characterization three new organic D-π-A dyes (WN1, WN3,...
Atomic layer deposition (ALD) was used to fabricate Al2O3 recombination barriers in solid-state dye-sensitized solar cells (ss-DSSCs) employing an organic hole transport material (HTM) for the first time. of varying thickness were incorporated into efficient ss-DSSCs utilizing Z907 dye adsorbed onto a 2 μm-thick nanoporous TiO2 active and HTM spiro-OMeTAD. The impact also studied devices different dyes, with increased thicknesses, substrates that did not undergo TiCl4 surface treatment. In...
Thermal and environmental stability of metal halide perovskite solar cells remains a major barrier to their commercialization. The industry standard transparent electrode, ITO, has good optoelectronic properties high stability. We introduce robust buffer layer by solution-processing AZO nanoparticles, enabling sputtered amorphous ITO without damaging the underlying device. make both semitransparent (12.3%) mechanically stacked tandems (12.3% + 5.7% = 18.0%) using monocrystalline-silicon as...
With the advent of high-bandgap perovskites, opportunity now exists to make tandems with perovskites on top silicon. We have prototyped a mechanically stacked tandem, achieving 17.9% certified efficiency using perovskite cell silver nanowire mesh electrode. also monolithically integrated tandem silicon, two subcells electronically connected by band-to-band tunneling in The primary challenges propelling perovskite/silicon into high-efficiency (>25%) regime are spiro-OMeTAD parasitic...
Coupling perovskite and silicon solar cells in a tandem configuration is considered an attractive method to increase conversion efficiency beyond the single-junction Shockley-Queisser limit. While mechanically-stacked perovskite/silicon cell has been demonstrated, electrically couple monolithic not demonstrated. In this contribution, we design demonstrate working cell, enabled by tunnel junction, with VOC of 1.58 V. We further discuss possible loss mechanisms mitigation strategies.
This work evaluates the critical issues surrounding P1, P2, and P3 scribing for semi-transparent perovskite module integration. We find that P1 procedures are well-translated from other thin-film technologies. P2 is best performed with a mechanical scribe, but remains source of series resistance. found to cause an increase in dead area potential degradation source.
Significant progress is being made in scaling metal halide perovskite solar module technology for fabricating durable efficient sub modules suitable high-efficiency mechanically-stacked / silicon tandem modules. Semi-transparent 100 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> submodule efficiencies of 16% have been achieved using scalable non-vacuum processing films; refinements raw materials selection, superstrate preparation,...