Cadmium telluride (CdTe) is a crystalline compound formed from cadmium and tellurium. It is a black cubic crystalline powder. It is used as an infrared optical window and a solar cell material. It is usually sandwiched with cadmium sulfide to form a p-n junction photovoltaic solar cell. Typically, CdTe cells use a n-i-p structure.
Cadmium Telluride (CdTe) Chemical Properties Available:
GCdTe has very low solubility in water. It is etched by many acids including hydrochloric, and hydrobromic acid, forming (toxic) hydrogen telluride gas.
1) CdTe is a highly useful material in the making of thin film solar cells. Thin-film CdTe provides a cost-effective solar cell design, but is less efficient than polysilicon.
2) CdTe photovoltaics describes a photovoltaic (PV) technology that is based on the use of cadmium telluride thin film, a semiconductor layer designed to absorb and convert sunlight into electricity. Cadmium telluride PV (CdTe PV) is the first and only thin film photovoltaic technology to surpass crystalline silicon PV in cheapness for a significant portion of the PV market—great (multi-kW) systems.
3) CdTe can be alloyed with mercury to make a versatile infrared detector material (HgCdTe). CdTe alloyed with a small amount of zinc makes an excellent solid-state X-ray and gamma ray detector (CdZnTe).
4) CdTe is used as an infrared optical material for optical windows and lenses but it has small application and is limited by its toxicity such that few optical houses will consider working with it. An early form of CdTe for IR use was marketed under the trademarked name of Irtran-6 but this is obsolete.
5) CdTe is also applied for electro-optic modulators. It has the greatest electro-optic coefficient of the linear electro-optic effect among II-VI compound crystals (r41=r52=r63=6.8×10-12 m/V).
6) CdTe doped with chlorine is used as a radiation detector for x-rays, gamma rays, beta particles and alpha particles. CdTe can operate at room temperature allowing the construction of compact detectors for a wide variety of applications in nuclear spectroscopy. Source: Wikipedia
Cadmium Telluride (CdTe) Industry 2011:
Cadmium Telluride (CdTe) Packaging:
Jars, pails, drums. For further information on packaging options contact READE
Cadmium Telluride (CdTe) TSCA (SARA Title III) Status:
Listed. For further information please call the E.P.A. at +1.202.554.1404
Cadmium Telluride (CdTe) CAS Number:
Cadmium Telluride (CdTe) Toxicity Information:
1) Cadmium telluride is toxic, but only so if ingested, its dust inhaled, or if it is handled improperly (i.e. without appropriate gloves and other safety precautions). Once properly and securely captured and encapsulated, CdTe used in manufacturing processes may be rendered harmless.
2) The toxicity is not solely due to the cadmium content. One study found that the highly reactive surface of cadmium telluride quantum dots triggers extensive reactive oxygen damage to the cell membrane, mitochondria, and cell nucleus. Many nanoparticle chemicals have safety issues. In addition, the cadmium telluride films are typically recrystallized in a toxic compound of cadmium chloride.
3) The disposal and long term safety of cadmium telluride is a known issue in the large scale commercialization of cadmium telluride solar panels. Serious efforts have been made to understand and overcome these issues. A document hosted by the U.S. National Institutes of Health dated 2003 discloses that:
4) Brookhaven National Laboratory (BNL) and the U.S. Department of Energy (DOE) are nominating Cadmium Telluride (CdTe) for inclusion in the National Toxicology Program (NTP). This nomination is strongly supported by the National Renewable Energy Laboratory (NREL) and First Solar Inc. The material has the potential for widespread applications in photovoltaic energy generation that will involve extensive human interfaces. Hence, we consider that a definitive toxicological study of the effects of long-term exposure to CdTe is a necessity.
5) Researchers from the U.S. Department of Energy's Brookhaven National Laboratory have found that large-scale use of CdTe PV modules does not present any risks to health and the environment, and recycling the modules at the end of their useful life completely resolves any environmental concerns. During their operation, these modules do not produce any pollutants, and furthermore, by displacing fossil fuels, they offer great environmental benefits. CdTe PV modules appear to be more environmentally friendly than all other current uses of Cd.
6) The approach to CdTe safety in the European Union and China is much more cautious: cadmium and cadmium compounds are considered as toxic carcinogens in EU whereas China regulations allow Cd products for export only. The major concern for CdTe is inevitable presence of Cd during CdTe production and processing.
"GE to Build Large Solar Factory in U.S." GE will build what could be the largest solar panel factory in the United States. The plant will be the culmination of over $600 million worth of investment in cadmium telluride thin film solar technology over that past few years. The factory will produce 400 megawatts of solar panels a year. Visit This Link