Quantum Dot Solar Cells. Semiconductor Nanocrystals as Light Harvesters
18 Oct 2008-Journal of Physical Chemistry C (American Chemical Society)-Vol. 112, Iss: 48, pp 18737-18753
TL;DR: In this paper, three major ways to utilize semiconductor dots in solar cell include (i) metal−semiconductor or Schottky junction photovoltaic cell, (ii) polymer−smiconductor hybrid solar cell, and (iii) quantum dot sensitized solar cell.
Abstract: The emergence of semiconductor nanocrystals as the building blocks of nanotechnology has opened up new ways to utilize them in next generation solar cells. This paper focuses on the recent developments in the utilization of semiconductor quantum dots for light energy conversion. Three major ways to utilize semiconductor dots in solar cell include (i) metal−semiconductor or Schottky junction photovoltaic cell (ii) polymer−semiconductor hybrid solar cell, and (iii) quantum dot sensitized solar cell. Modulation of band energies through size control offers new ways to control photoresponse and photoconversion efficiency of the solar cell. Various strategies to maximize photoinduced charge separation and electron transfer processes for improving the overall efficiency of light energy conversion are discussed. Capture and transport of charge carriers within the semiconductor nanocrystal network to achieve efficient charge separation at the electrode surface remains a major challenge. Directing the future resear...
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TL;DR: This work reviews the historical development of Transition metal dichalcogenides, methods for preparing atomically thin layers, their electronic and optical properties, and prospects for future advances in electronics and optoelectronics.
Abstract: Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.
13,348 citations
TL;DR: Dye-sensitized solar cells (DSCs) offer the possibilities to design solar cells with a large flexibility in shape, color, and transparency as mentioned in this paper, and many DSC research groups have been established around the world.
Abstract: Dye-sensitized solar cells (DSCs) offer the possibilities to design solar cells with a large flexibility in shape, color, and transparency. DSC research groups have been established around the worl ...
8,707 citations
TL;DR: Nanocrystals (NCs) discussed in this Review are tiny crystals of metals, semiconductors, and magnetic material consisting of hundreds to a few thousand atoms each that are among the hottest research topics of the last decades.
Abstract: Nanocrystals (NCs) discussed in this Review are tiny crystals of metals, semiconductors, and magnetic material consisting of hundreds to a few thousand atoms each. Their size ranges from 2-3 to about 20 nm. What is special about this size regime that placed NCs among the hottest research topics of the last decades? The quantum mechanical coupling * To whom correspondence should be addressed. E-mail: dvtalapin@uchicago.edu. † The University of Chicago. ‡ Argonne National Lab. Chem. Rev. 2010, 110, 389–458 389
3,720 citations
TL;DR: In this paper, the development of different strategies to modify TiO2 for the utilization of visible light, including non metal and/or metal doping, dye sensitization and coupling semiconductors are discussed.
Abstract: Fujishima and Honda (1972) demonstrated the potential of titanium dioxide (TiO2) semiconductor materials to split water into hydrogen and oxygen in a photo-electrochemical cell. Their work triggered the development of semiconductor photocatalysis for a wide range of environmental and energy applications. One of the most significant scientific and commercial advances to date has been the development of visible light active (VLA) TiO2 photocatalytic materials. In this review, a background on TiO2 structure, properties and electronic properties in photocatalysis is presented. The development of different strategies to modify TiO2 for the utilization of visible light, including non metal and/or metal doping, dye sensitization and coupling semiconductors are discussed. Emphasis is given to the origin of visible light absorption and the reactive oxygen species generated, deduced by physicochemical and photoelectrochemical methods. Various applications of VLA TiO2, in terms of environmental remediation and in particular water treatment, disinfection and air purification, are illustrated. Comprehensive studies on the photocatalytic degradation of contaminants of emerging concern, including endocrine disrupting compounds, pharmaceuticals, pesticides, cyanotoxins and volatile organic compounds, with VLA TiO2 are discussed and compared to conventional UV-activated TiO2 nanomaterials. Recent advances in bacterial disinfection using VLA TiO2 are also reviewed. Issues concerning test protocols for real visible light activity and photocatalytic efficiencies with different light sources have been highlighted.
3,305 citations
TL;DR: In this paper, the authors discussed the steps that have led to this discovery, and the future of this rapidly advancing concept have been considered, and it is likely that the next few years of solar research will advance this technology to the very highest efficiencies while retaining the very lowest cost and embodied energy.
Abstract: Over the last 12 months, we have witnessed an unexpected breakthrough and rapid evolution in the field of emerging photovoltaics, with the realization of highly efficient solid-state hybrid solar cells based on organometal trihalide perovskite absorbers. In this Perspective, the steps that have led to this discovery are discussed, and the future of this rapidly advancing concept have been considered. It is likely that the next few years of solar research will advance this technology to the very highest efficiencies while retaining the very lowest cost and embodied energy. Provided that the stability of the perovskite-based technology can be proven, we will witness the emergence of a contender for ultimately low-cost solar power.
2,506 citations
References
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TL;DR: One-dimensional semiconductor subwavelength optical elements are capable of efficiently guiding light through liquid media, suggesting a role for such materials in microfluidics-based biosensing applications.
Abstract: This article focuses on one-dimensional (1D) semiconductor subwavelength optical elements and assesses their potential use as active and passive components in photonic devices. An updated overview of their optical properties, including spontaneous emission, ultrafast carrier dynamics, cavity resonance feedback (lasing), photodetection, and waveguiding, is provided. The ability to physically manipulate these structures on surfaces to form simple networks and assemblies is the first step toward integrating chemically synthesized nanomaterials into photonic circuitry. These high index semiconductor nanowires are capable of efficiently guiding light through liquid media, suggesting a role for such materials in microfluidics-based biosensing applications.
283 citations
TL;DR: In this paper, a colloidal CdS-ZnO system in a photoelectrochemical cell has been demonstrated by modifying the surface of an optically transparent electrode with ZnO and cdS colloids.
Abstract: Picosecond laser flash photolysis and photoelectrochemical studies have been carried out to elucidate the charge-transfer processes in CdS-ZnO coupled semiconductor systems. Charge injection from excited CdS into ZnO occurs within the laser pulse duration of 18 ps. Long-lived trapped charge carriers demonstrate the improved charge separation in CdS-ZnO coupled semiconductor systems. The feasibility of employing a colloidal CdS-ZnO system in a photoelectrochemical cell has been demonstrated by modifying the surface of an optically transparent electrode with ZnO and CdS colloids. Charge injection from excited CdS into ZnO particle on the electrode with ZnO and CdS colloids. Charge injection from excited CdS into ZnO particle on the electrode surface is confirmed by recording the photocurrent action spectra. An incident photon-to-photocurrent conversion efficiency of 15% has been observed for OTE/ZnO/CdS at 420 nm. 26 refs., 11 figs.
281 citations
TL;DR: In this article, photoelectrochemical (PEC) measurements showed that the electroless etching SiNWs are remarkably photoactive and effective in enhancing photovoltaic properties including photocurrent and photowage.
Abstract: Silicon nanowires (SiNWs) arrays prepared by electroless etching show excellent optical antireflectivity over a wide spectral bandwidth from 300to1000nm and surface defect-induced electrical conductivity. Both characteristics make the SiNWs a promising material for photovoltaic cell applications. Photoelectrochemical (PEC) measurements showed the electroless etching SiNWs are remarkably photoactive and effective in enhancing photovoltaic properties including photocurrent and photovoltage. Since electroless etching can enable simple, wafer-scale fabrication of SiNWs without the need of doping. SiNWs array thus prepared show great promise as low-cost and scalable photovoltaic-type PEC materials.
278 citations
TL;DR: The formation of nanostructured materials through the assembly of nanocrystals is described, focusing in particular on silica and other metal oxide coated core particles as discussed by the authors, and some of the unique properties of core−shell materials are presented.
Abstract: The formation of nanostructured materials through the assembly of nanocrystals is described, focusing in particular on silica and other metal oxide coated core particles. The preparation and optical characterization of core−shell materials are reviewed, and some of the unique properties of core−shell materials are presented. Shell layers are shown to serve various functions. They may increase colloid stability, aid dispersion in various media, alter the optical and electrical properties of the core, add robustness, or provide a contiguous framework from which inverse lattices may be generated. The assembly of the particles into well-defined thin films and two-dimensional and three-dimensional crystals is discussed, and the resultant optical properties are reviewed. Approaches to increase the topological complexity are studied, and the potential for the creation of a variety of space-filling nanostructures (such as inverse lattices, opals, and photonic crystals) is illustrated.
274 citations
TL;DR: In this paper, the effect of polymer thickness, hole mobility, and morphology on the device properties of polymer-based photovoltaics consisting of MEH-PPV as the optically active layer, TiO as the exciton dissociation surface, and ITO and Au electrodes.
Abstract: We study the effect of polymer thickness, hole mobility, and morphology on the device properties of polymer-based photovoltaics consisting of MEH-PPV as the optically active layer, ${\mathrm{TiO}}_{2}$ as the exciton dissociation surface, and ITO and Au electrodes. We demonstrate that the conversion efficiency in these polymer-based photovoltaics is primarily limited by the short exciton diffusion length combined with a low carrier mobility. For MEH-PPV devices with optimal device geometry, we achieve quantum efficiencies of 6% at the maximum absorption of the polymer, open circuit voltages of 1.1 V, current densities of 0.4 ${\mathrm{m}\mathrm{A}/\mathrm{c}\mathrm{m}}^{2}$ and rectification ratios greater than ${10}^{5}$ under 100 ${\mathrm{m}\mathrm{W}/\mathrm{c}\mathrm{m}}^{2}$ white light illumination. In addition, we achieve fill factors up to 42% at high light intensities and as high as 69% at low light intensities. We conclude by presenting a model that describes charge transport in ${\mathrm{s}\mathrm{o}\mathrm{l}\mathrm{i}\mathrm{d}\ensuremath{-}\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t}\mathrm{e}\phantom{\rule{0ex}{0ex}}\mathrm{p}\mathrm{o}\mathrm{l}\mathrm{y}\mathrm{m}\mathrm{e}\mathrm{r}/\mathrm{T}\mathrm{i}\mathrm{O}}_{2}$-based photovoltaics and suggest methods for improving energy conversion efficiencies in polymer-based photovoltaics.
269 citations