Photovoltaic cell performance can be greatly improved by optimising the transparent conducting oxide used as the front contact. We have developed an advanced atmospheric pressure chemical vapour ...deposition (APCVD) process, by applying fast experimentation and using a combinatorial chemistry approach to aid the studies. By use of this process, F-doped SnO2 has been deposited using either monobutyl tin trichloride or tin tetrachloride with aqueous HF or trifluoro-acetic acid as the dopant source. The deposited films were characterised for crystallinity, morphology, resistivity and growth rate to aid optimisation of material suitable for solar cells. The results from use of the different tin precursors and dopants were compared. The most striking changes were related to resistivity and surface morphology. Compared with commercially available TCO CVD coated glasses, our coatings show excellent performance resulting in a high quantum efficiency yield for a-Si:H solar cells.
We apply optical transmittance and reflectance spectroscopy, photothermal deflection spectroscopy (PDS) and laser calorimetry (LC) to evaluate optical absorption losses at rough interface between ...thin conductive oxide (TCO) and metal films used as backreflectors and electrical contacts in thin film solar cells. The paper proposes a simple method how to model the dielectric function of rough metal layers used in thin film solar cells. We show that the rough metal layer optically behaves as a semi‐infinite layer with modified dielectric function calculated by the Landau–Lifshitz–Looyenga (LLL) model from the dielectric function of a smooth metal, the dielectric function of TCO and just one free parameter that needs to be found by fitting the total optical absorptance. This approach can be used to simplify the modelling of the optical properties of thin film solar cells.
In Situ Bioremediation National Research Council; Division on Engineering and Physical Sciences; Commission on Engineering and Technical Systems ...
01/2000
eBook
Odprti dostop
In situ bioremediation?the use of microorganisms for on-site removal of contaminants?is potentially cheaper, faster, and safer than conventional cleanup methods. But in situ bioremediation is also ...clouded in uncertainty, controversy, and mistrust.
This volume from the National Research Council provides direction for decisionmakers and offers detailed and readable explanations of:
the processes involved in in situ bioremediation,
circumstances in which it is best used, and
methods of measurement, field testing, and modeling to evaluate the results of bioremediation projects.
Bioremediation experts representing academic research, field practice, regulation, and industry provide accessible information and case examples; they explore how in situ bioremediation works, how it has developed since its first commercial use in 1972, and what research and education efforts are recommended for the future. The volume includes a series of perspective papers.
The book will be immediately useful to policymakers, regulators, bioremediation practitioners and purchasers, environmental groups, concerned citizens, faculty, and students.
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