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Interaction of bacteriochlorophyll c and its derivative with titanium dioxide
Ridzoňová, Katarína ; Pšenčík, Jakub (advisor) ; Alster, Jan (referee)
Dye-sensitized solar cells (DSSC) are promising low-cost molecular photovoltaic devices that have a good chance to become a competitor for solar cells based on technology of p-n junction. One of the key components of DSSC is a dye, which is responsible for the capture of light. The main goal of this bachelor thesis is to compare adsorption properties of bacteriochlorophyll c (BChl c) and its modified version referred as bacteriochlorophyllide c (BChlide c) on titanium dioxide (TiO2). In the experimental part of this work interaction of these two sensitizing dyes with TiO2 were investigated by several different methods, including absorption spectroscopy and measuring photo-induced current and current-voltage characteristics of the fabricated DSSC. It has been shown, that BChlide c adsorbs better on the TiO2 layer presumably due to the presence of a carboxylate group. Also the performance of the DSSC based on BChlide c was better than with BChl c.
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Charge transport optical characterization in semiconductor radiation detectors
Ridzoňová, Katarína ; Belas, Eduard (advisor)
Measurements of DC photocurrent-voltage characteristic, photocurrents spectral response and laser induced transient current technique enable investigation of surface recombination centers, bulk trap levels and distribution of the inner electric field. In the presented work, the n- type planar CdZnTe detectors with quasi Ohmic contacts were studied by above mentioned methods. It has been shown that in the case of strongly absorbed light under the DC regime of illumination not only surface recombination influences the detector's transport properties. The effect of the space charge, created as a consequence of carriers trapped by the impurity levels, must be taken into account. Therefore some new theoretical models were created in order to describe measured photocurrent-voltage dependencies. Obtained data were fitted with the new theory and the mobility and surface recombination velocity for electrons were determined.
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Charge transport optical characterization in semiconductor radiation detectors
Ridzoňová, Katarína ; Belas, Eduard (advisor)
Measurements of DC photocurrent-voltage characteristic, photocurrents spectral response and laser induced transient current technique enable investigation of surface recombination centers, bulk trap levels and distribution of the inner electric field. In the presented work, the n- type planar CdZnTe detectors with quasi Ohmic contacts were studied by above mentioned methods. It has been shown that in the case of strongly absorbed light under the DC regime of illumination not only surface recombination influences the detector's transport properties. The effect of the space charge, created as a consequence of carriers trapped by the impurity levels, must be taken into account. Therefore some new theoretical models were created in order to describe measured photocurrent-voltage dependencies. Obtained data were fitted with the new theory and the mobility and surface recombination velocity for electrons were determined.
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Charge transport optical characterization in semiconductor radiation detectors
Ridzoňová, Katarína ; Belas, Eduard (advisor) ; Toušek, Jiří (referee)
Measurements of DC photocurrent-voltage characteristic, photocurrents spectral response and laser induced transient current technique enable investigation of surface recombination centers, bulk trap levels and distribution of the inner electric field. In the presented work, the n- type planar CdZnTe detectors with quasi Ohmic contacts were studied by above mentioned methods. It has been shown that in the case of strongly absorbed light under the DC regime of illumination not only surface recombination influences the detector's transport properties. The effect of the space charge, created as a consequence of carriers trapped by the impurity levels, must be taken into account. Therefore some new theoretical models were created in order to describe measured photocurrent-voltage dependencies. Obtained data were fitted with the new theory and the mobility and surface recombination velocity for electrons were determined.
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Interaction of bacteriochlorophyll c and its derivative with titanium dioxide
Ridzoňová, Katarína ; Pšenčík, Jakub (advisor) ; Alster, Jan (referee)
Dye-sensitized solar cells (DSSC) are promising low-cost molecular photovoltaic devices that have a good chance to become a competitor for solar cells based on technology of p-n junction. One of the key components of DSSC is a dye, which is responsible for the capture of light. The main goal of this bachelor thesis is to compare adsorption properties of bacteriochlorophyll c (BChl c) and its modified version referred as bacteriochlorophyllide c (BChlide c) on titanium dioxide (TiO2). In the experimental part of this work interaction of these two sensitizing dyes with TiO2 were investigated by several different methods, including absorption spectroscopy and measuring photo-induced current and current-voltage characteristics of the fabricated DSSC. It has been shown, that BChlide c adsorbs better on the TiO2 layer presumably due to the presence of a carboxylate group. Also the performance of the DSSC based on BChlide c was better than with BChl c.
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