CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were...CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction（SILAR） method to serve as the sensitizers. Cd（NO3）2 and Na2S were used as the precursor materials of Cd＋ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations（100 mW cm^-2）, a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.展开更多
The photovoltaic performance of alloyed CdTe0.6S0.4 quantum dot sensitized solar cells (QDSSCs) is investigated. Fluorine doped Tin Oxide (FTO) substrates were coated with 20 nm-diameter TiO2 nanoparticles (NPs). Pres...The photovoltaic performance of alloyed CdTe0.6S0.4 quantum dot sensitized solar cells (QDSSCs) is investigated. Fluorine doped Tin Oxide (FTO) substrates were coated with 20 nm-diameter TiO2 nanoparticles (NPs). Presynthesized colloidal solution of alloyed CdTe0.6S0.4 quantum dots (QDs) of 4.2 nm was deposited onto TiO2 NPs substrates using direct adsorption (DA) technique, by dipping for different times at ambient conditions. The FTO counter electrodes were coated with platinum, while the electrolyte containing I-/I-3 redox species was sandwiched between the two electrodes. Compared to pure CdTe QDs and CdS QDs, CdTe0.6S0.4 QDs showed better photovoltaic performance. The J-V characteristic curves of the assembled QDSSCs were measured at AM 1.5 simulated sunlight. The short current density (Jsc) and efficiency (η) increase with dipping time. At 24 h dipping time, the open-circuit photovoltage Voc, Jsc, fill factor (FF), and η were 0.46 volts, 1.54 mA/cm2, 0.43% and 0.31%, respectively.展开更多
The photovoltaic performance of CdS quantum dots sensitized solar cells （QDSSCs） using the 0.2 wt% of reduced graphene oxide and TiO2 nanoparticles （RGO＋TiO2 nanocomposite） photoanode is investigated. CdS QDs are...The photovoltaic performance of CdS quantum dots sensitized solar cells （QDSSCs） using the 0.2 wt% of reduced graphene oxide and TiO2 nanoparticles （RGO＋TiO2 nanocomposite） photoanode is investigated. CdS QDs are adsorbed onto RGO＋TiO2 nanocomposite films by the successive ionic layer adsorption and reaction （SILAR） technique for several cycles. The current density-voltage （J-V） characteristic curves of the assembled QDSSCs are measured at AM1.5 simulated sunlight. The optimal photovoltaic performance for CdS QDSSC was achieved for six SILAR cycles. Solar cells based on the RGO＋TiO2 nanocomposite photoanode achieve a 33% increase in conversion efficiency （η） compared with those based on plain TiO2 nanoparticle （NP） photoanodes. The electron back recombination rates decrease significantly for CdS QDSSCs based on RGO＋TiO2 nanocomposite photoanodes. The lifetime constant （τ） for CdS QDSSC based on the RGO＋TiO2 nanocomposite photoanode is at least one order of magnitude larger than that based on the bare TiO2NPs photoanode.展开更多
基金Funded by Major State Basic Research Development Program of China (973 Program) (No.2009CB939704)Key Project of Chinese Ministry of Education (No.309021)
文摘CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction（SILAR） method to serve as the sensitizers. Cd（NO3）2 and Na2S were used as the precursor materials of Cd＋ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations（100 mW cm^-2）, a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.
文摘The photovoltaic performance of alloyed CdTe0.6S0.4 quantum dot sensitized solar cells (QDSSCs) is investigated. Fluorine doped Tin Oxide (FTO) substrates were coated with 20 nm-diameter TiO2 nanoparticles (NPs). Presynthesized colloidal solution of alloyed CdTe0.6S0.4 quantum dots (QDs) of 4.2 nm was deposited onto TiO2 NPs substrates using direct adsorption (DA) technique, by dipping for different times at ambient conditions. The FTO counter electrodes were coated with platinum, while the electrolyte containing I-/I-3 redox species was sandwiched between the two electrodes. Compared to pure CdTe QDs and CdS QDs, CdTe0.6S0.4 QDs showed better photovoltaic performance. The J-V characteristic curves of the assembled QDSSCs were measured at AM 1.5 simulated sunlight. The short current density (Jsc) and efficiency (η) increase with dipping time. At 24 h dipping time, the open-circuit photovoltage Voc, Jsc, fill factor (FF), and η were 0.46 volts, 1.54 mA/cm2, 0.43% and 0.31%, respectively.
基金Project supported by the Fund from Taif University,Saudi Arabia(Grant No.1/435/3524)
文摘The photovoltaic performance of CdS quantum dots sensitized solar cells （QDSSCs） using the 0.2 wt% of reduced graphene oxide and TiO2 nanoparticles （RGO＋TiO2 nanocomposite） photoanode is investigated. CdS QDs are adsorbed onto RGO＋TiO2 nanocomposite films by the successive ionic layer adsorption and reaction （SILAR） technique for several cycles. The current density-voltage （J-V） characteristic curves of the assembled QDSSCs are measured at AM1.5 simulated sunlight. The optimal photovoltaic performance for CdS QDSSC was achieved for six SILAR cycles. Solar cells based on the RGO＋TiO2 nanocomposite photoanode achieve a 33% increase in conversion efficiency （η） compared with those based on plain TiO2 nanoparticle （NP） photoanodes. The electron back recombination rates decrease significantly for CdS QDSSCs based on RGO＋TiO2 nanocomposite photoanodes. The lifetime constant （τ） for CdS QDSSC based on the RGO＋TiO2 nanocomposite photoanode is at least one order of magnitude larger than that based on the bare TiO2NPs photoanode.
