(2N) 99% • (3N) 99.9% • (4N) 99.99% • (5N) 99.999% • (6N) 99.9999%
SOLAR ENERGY INFORMATION CENTER
AE Solar Energy™
American Elements is a manufacturer and supplier specializing in materials essential to several photovoltaic solar energy technologies.
When the sun's energy in the form of photons collects in the cell layers in a volume sufficient to force electrons in the layer materials from their "Valence Band" to their "Conduction Band", electrons from the layers are released. This energy threshold is referred to as the "Band Gap". These freed electrons naturally attempt to flow from the negatively charge n-type layer to the positively charged p-type layer. For this reason, the p-type layer is also sometimes called the "Absorption Layer" and the n-type layer is called the "Emitter Layer".
However, the boundary between these two layers, which is called the "P-N Junction" or "Adhesion Layer" blocks their flow. Collection circuits are attached from the n-type layer to the p-type layer to allow for the electrons to reach their target and complete the circuit. Energy in the form of electricity is collected or harvested from this external circuit.
The history of solar energy materials began in the 1970s with the first silicon-based photovoltaic (PV) cells. These basic cells were created by doping silicon to form two oppositely charged layers. A positively charged or p-type layer underneath a negatively charged or n-type layer. In first configurations the p-type layer was doped with boron to create the positive charge and n-type layer was doped with phosphorous.
These silicon based photovoltaic cells have gone through several generations of development designed to reduce production costs. Originally the layers were produced by growing and slicing doped single crystals of silicon. To save cost producers began casting shapes using polycrystalline silicon. While less expensive to produce, efficiencies are also lower. A silicon single crystal may have as high as 30% efficiency; polycrystalline silicon might reach 10-15%. The least expensive approach but also the least efficient cell (approximately 5%) is produced through thin film deposition of amorphous silicon using sputtering techniques.
Presently, most silicon-based PV solar cells are produced from polycrystalline silicon with single crystal systems the next most common.
All silicon-based photovoltaic solar energy collectors, however, suffer from their ability to absorb energy from a relatively narrow range of the sun's light wave emission. Substantial research ha gone into developing materials that can either expand the band gap or create multiple band gaps in order to absorb a greater portion of the solar energy spectrum. This has lead to the development of PV cells based on Copper Indium Selenide (CuInSe2) or "CIS" Absorption Layers which can capture energy from portions of the light's spectrum not collected by silicon-based PV cells. Doping CIS with Gallium increases the band gap even further and as such most PV cells are now based on Copper Indium Gallium Selenide (CuInGaSe2) and are referred to as "CIGS".
In the typical CIGS photovoltaic cell, the CIGS layer acts as the the p-type or absorption layer. A second material, Cadmium Selenide (CdSe) functions as the emitter or n-type layer. Because two different materials are uses these are sometimes referred to as "Heterojunction" systems. The external circuit is provided by a zinc oxide contact layer on the n-type layer and a Molybdenum metal contact layer on the p-type layer.
CIGS based solar cells are a rapidly growing segment of the solar energy market. Besides being more efficient that silicon-based solar cells and therefore less expensive per watt of energy generated, they can be designed to bend to complex geometries and are very light weight. Due to their high efficiency, layers can be achieved using thin film techniques. Thin film deposition of Silicon Nanoparticle quantum dots on the polycrystalline silicon substrate of a photovoltaic (solar) cell increases voltage output as much as 60% by fluorescing the incoming light prior to capture.
The band gap for III-IV Nitride materials, such as Gallium Indium Nitride, covers nearly the entire energy spectrum of the sun because of multiple band gaps in the semiconductor materials. Similarly, Zinc Manganese Telluride crystals have three band gaps which can absorb greater than 50% of the solar energy spectrum.
Further important research involves nanotechnology approaches using nanoparticles of the above materials. Below please find further technical and safety information on solar energy materials manufactured by American Elements' AE Solar Energy™ group.
AE Solar Energy™ Materials
Recent Research & Development for Solar Energy
- Yike Liu, Mengmeng Hao, Jia Yang, Liangxing Jiang, Chang Yan, Chun Huang, Ding Tang, Fangyang Liu, Yexiang Liu, Colloidal synthesis of Cu2FeSnSe4 nanocrystals for solar energy conversion, Materials Letters, Volume 136, 1 December 2014
- Taiping Zhang, Paul W. Stackhouse Jr., William S. Chandler, David J. Westberg, Application of a global-to-beam irradiance model to the NASA GEWEX SRB dataset: An extension of the NASA Surface meteorology and Solar Energy datasets, Solar Energy, Volume 110, December 2014
- Ed Constable, Molecular materials for solar energy conversion, Polyhedron, Volume 82, 4 November 2014
- Panagiotis A. Angaridis, Theodore Lazarides, Athanassios C. Coutsolelos, Functionalized porphyrin derivatives for solar energy conversion, Polyhedron, Volume 82, 4 November 2014
- L.E.G. Cambronero, I. Cañadas, J.M. Ruiz-Román, M. Cisneros, F.A. Corpas Iglesias, Weld structure of joined aluminium foams with concentrated solar energy, Journal of Materials Processing Technology, Volume 214, Issue 11, November 2014
- A.S. Budiman, G. Illya, V. Handara, W.A. Caldwell, C. Bonelli, M. Kunz, N. Tamura, D. Verstraeten, Enabling thin silicon technologies for next generation c-Si solar PV renewable energy systems using synchrotron X-ray microdiffraction as stress and crack mechanism probe, Solar Energy Materials and Solar Cells, Volume 130, November 2014
- Hyun-Young Kim, Won-Yeob Rho, Hea Yeon Lee, Young Seok Park, Jung Sang Suh, Aggregation effect of silver nanoparticles on the energy conversion efficiency of the surface plasmon-enhanced dye-sensitized solar cells, Solar Energy, Volume 109, November 2014
- Fritz Zaversky, Rodrigo Medina, Javier Garcìa-Barberena, Marcelino Sànchez, David Astrain, Corrigendum to “Object-oriented modeling for the transient performance simulation of parabolic trough collectors using molten salt as heat transfer fluid” [Solar Energy 95 (2013) 192–215], Solar Energy, Volume 109, November 2014
- Feng He, Fanxing Li, Hydrogen production from methane and solar energy – Process evaluations and comparison studies, International Journal of Hydrogen Energy, Volume 39, Issue 31, 22 October 2014
- Liang Li, Yulin Yang, Ruiqing Fan, Yanxia Jiang, Liguo Wei, Yan Shi, Jia Yu, Shuo Chen, Ping Wang, Bin Yang, Wenwu Cao, A simple modification of near-infrared photon-to-electron response with fluorescence resonance energy transfer for dye-sensitized solar cells, Journal of Power Sources, Volume 264, 15 October 2014