Biomaterial Database

The transitional heterojunction behavior of PbS/ZnO colloidal quantum dot solar cells. 2012

Shawn M Willis, and Cheng Cheng, and Hazel E Assender, and Andrew A R Watt

Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom.

The nature of charge separation at the heterojunction interface of solution processed lead sulphide-zinc oxide colloidal quantum dot solar cells is investigated using impedance spectroscopy and external quantum efficiency measurements to examine the effect of varying the zinc oxide doping density. Without doping, the device behaves excitonically with no depletion region in the PbS layer such that only charge carriers generated within a diffusion length of the PbS/ZnO interface have a good probability of being harvested. After the ZnO is photodoped such that the doping density is near or greater than that of the PbS, a significant portion of the depletion region is found to lie within the PbS layer increasing charge extraction (p-n operation).

UI	MeSH Term	Description	Entries
D007854	Lead	A soft, grayish metal with poisonous salts; atomic number 82, atomic weight 207.2, symbol Pb.
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D011211	Electric Power Supplies	Devices that control the supply of electric current for running electrical equipment.	Power Sources,Power Supplies,Electric Power Sources,Power Sources, Electric,Power Supplies, Electric,Electric Power Source,Electric Power Supply,Power Source,Power Source, Electric,Power Supply,Power Supply, Electric,Supply, Electric Power
D004867	Equipment Design	Methods and patterns of fabricating machines and related hardware.	Design, Equipment,Device Design,Medical Device Design,Design, Medical Device,Designs, Medical Device,Device Design, Medical,Device Designs, Medical,Medical Device Designs,Design, Device,Designs, Device,Designs, Equipment,Device Designs,Equipment Designs
D012666	Semiconductors	Materials that have a limited and usually variable electrical conductivity. They are particularly useful for the production of solid-state electronic devices.	Semiconductor
D012993	Solar Energy	Energy transmitted from the sun in the form of electromagnetic radiation.	Solar Power,Energies, Solar,Energy, Solar,Power, Solar,Solar Energies
D015034	Zinc Oxide	A mild astringent and topical protectant with some antiseptic action. It is also used in bandages, pastes, ointments, dental cements, and as a sunblock.	Lassar's Paste,Lassar Paste,Lassars Paste,Oxide, Zinc,Paste, Lassar's
D045663	Quantum Dots	Nanometer sized fragments of semiconductor crystalline material which emit PHOTONS. The wavelength is based on the quantum confinement size of the dot. They can be embedded in MICROBEADS for high throughput ANALYTICAL CHEMISTRY TECHNIQUES.	Nanocrystals, Semiconductor,Semiconductor Nanocrystals,Semiconductor Nanoparticles,Dot, Quantum,Dots, Quantum,Nanocrystal, Semiconductor,Nanoparticle, Semiconductor,Nanoparticles, Semiconductor,Quantum Dot,Semiconductor Nanocrystal,Semiconductor Nanoparticle
D049329	Nanostructures	Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.	Nanomaterials,Nanostructured Materials,Material, Nanostructured,Materials, Nanostructured,Nanomaterial,Nanostructure,Nanostructured Material
D018036	Selenium Compounds	Inorganic compounds that contain selenium as an integral part of the molecule.	Compounds, Selenium