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Construction of metal oxide nanoparticles as anodes is of special interest for next-generation lithium-ion batteries. The main challenge lies in their rapid capacity fading caused by the structural degradation and instability of solid-electrolyte interphase (SEI) layer during charge/discharge process. Herein, we address these problems by constructing a novel-structured SnO2-based anode. The novel structure consists of mesoporous clusters of SnO2 quantum dots (SnO2 QDs), which are wrapped with reduced graphene oxide (RGO) sheets. The mesopores inside the clusters provide enough room for the expansion and contraction of SnO2 QDs during charge/discharge process while the integral structure of the clusters can be maintained. The wrapping RGO sheets act as electrolyte barrier and conductive reinforcement. When used as an anode, the resultant composite (MQDC-SnO2/RGO) shows an extremely high reversible capacity of 924 mAh g−1 after 200 cycles at 100 mA g−1, superior capacity retention (96%), and outstanding rate performance (505 mAh g−1 after 1000 cycles at 1000 mA g−1). Importantly, the materials can be easily scaled up under mild conditions. Our findings pave a new way for the development of metal oxide towards enhanced lithium storage performance.

This study reports evidences of dispersive transport in planar PbS colloidal quantum dots heterojunction-based devices as well as the effect of incorporating a MoO3 hole selective layer on the charge extraction behavior. Steady state and transient characterization techniques are employed to determine the complex recombination processes involved in such devices. The addition of a selective contact drastically improves the device efficiency up to 3.15 % (especially through the photocurrent and series resistance) and extends the overall charge lifetime by suppressing the main first-order recombination pathway observed in device without MoO3. The lifetime and mobility calculated for our sulphur-rich PbS-based devices are similar to previously reported values in lead-rich quantum dots-based solar cells. Nevertheless, strong Shockley-Read-Hall mechanisms appears to keep restricting charge transport, the equilibrium voltage taking more than 1 ms to be established.

We demonstrate a new strategy of boosting the efficiency of quantum dot sensitized solar cells (QDSSCs) by engineering the photocathode and photoanode simultaneously. Nanostructured photocathodes based on non-stoichiometric Cu2-xSe electrocatalysts were developed via a simple and scalable approach for CdS/CdSe QDs co-sensitized solar cells. Compared to Cu2S CE, remarkably improved photovoltaic performance was achieved for QDSSCs with Cu2-xSe CEs. The superior catalytic activity and electrical conductivity of Cu2-xSe CEs were verified by the electrochemical impedance spectra and Tafel-polarization measurements. To maximize the efficiency enhancement, the photoanodes were optimized by introducing a pillared porous titania composite as the scattering layers for further light harvesting and charge transfer improvement concurrently. The combination of effective Cu2-xSe electrocatalysts and pillared titania scattering layers contributed to one of the best reported efficiencies of 7.11% for CdS/CdSe QDs co-sensitized solar cells.

We demonstrate a new strategy of boosting the efficiency of quantum dot sensitized solar cells (QDSSCs) by engineering the photocathode and photoanode simultaneously. Nanostructured photocathodes based on non-stoichiometric Cu2-xSe electrocatalysts were developed via a simple and scalable approach for CdS/CdSe QDs co-sensitized solar cells. Compared to Cu2S CE, remarkably improved photovoltaic performance was achieved for QDSSCs with Cu2-xSe CEs. The superior catalytic activity and electrical conductivity of Cu2-xSe CEs were verified by the electrochemical impedance spectra and Tafel-polarization measurements. To maximize the efficiency enhancement, the photoanodes were optimized by introducing a pillared porous titania composite as the scattering layers for further light harvesting and charge transfer improvement concurrently. The combination of effective Cu2-xSe electrocatalysts and pillared titania scattering layers contributed to one of the best reported efficiencies of 7.11% for CdS/CdSe QDs co-sensitized solar cells.

This study reports evidences of dispersive transport in planar PbS colloidal quantum dots heterojunction-based devices as well as the effect of incorporating a MoO3 hole selective layer on the charge extraction behavior. Steady state and transient characterization techniques are employed to determine the complex recombination processes involved in such devices. The addition of a selective contact drastically improves the device efficiency up to 3.15 % (especially through the photocurrent and series resistance) and extends the overall charge lifetime by suppressing the main first-order recombination pathway observed in device without MoO3. The lifetime and mobility calculated for our sulphur-rich PbS-based devices are similar to previously reported values in lead-rich quantum dots-based solar cells. Nevertheless, strong Shockley-Read-Hall mechanisms appears to keep restricting charge transport, the equilibrium voltage taking more than 1 ms to be established.

This study reports evidences of dispersive transport in planar PbS colloidal quantum dots heterojunction-based devices as well as the effect of incorporating a MoO3 hole selective layer on the charge extraction behavior. Steady state and transient characterization techniques are employed to determine the complex recombination processes involved in such devices. The addition of a selective contact drastically improves the device efficiency up to 3.15 % (especially through the photocurrent and series resistance) and extends the overall charge lifetime by suppressing the main first-order recombination pathway observed in device without MoO3. The lifetime and mobility calculated for our sulphur-rich PbS-based devices are similar to previously reported values in lead-rich quantum dots-based solar cells. Nevertheless, strong Shockley-Read-Hall mechanisms appears to keep restricting charge transport, the equilibrium voltage taking more than 1 ms to be established.

We demonstrate a new strategy of boosting the efficiency of quantum dot sensitized solar cells (QDSSCs) by engineering the photocathode and photoanode simultaneously. Nanostructured photocathodes based on non-stoichiometric Cu2-xSe electrocatalysts were developed via a simple and scalable approach for CdS/CdSe QDs co-sensitized solar cells. Compared to Cu2S CE, remarkably improved photovoltaic performance was achieved for QDSSCs with Cu2-xSe CEs. The superior catalytic activity and electrical conductivity of Cu2-xSe CEs were verified by the electrochemical impedance spectra and Tafel-polarization measurements. To maximize the efficiency enhancement, the photoanodes were optimized by introducing a pillared porous titania composite as the scattering layers for further light harvesting and charge transfer improvement concurrently. The combination of effective Cu2-xSe electrocatalysts and pillared titania scattering layers contributed to one of the best reported efficiencies of 7.11% for CdS/CdSe QDs co-sensitized solar cells.

Using the molecular dynamic method we investigate numerically the current driven vortex motion in a superconducting film with periodic arrays of both ferromagnetic (FM) and anti-parallel ferromagnetic (AFM) dots. The simulation results show that in the absence of thermal fluctuation the vortex motion is dominated by the configurations of the magnetic dot array. This guided vortex motion is only observed at the onset of the depinning of the interstitial vortices. Two guided vortex motion mechanisms are discussed in this work. For the AFM configuration the vortex motion is mainly originated by the existence of magnetic dots with opposite magnetized moments, while for the FM case it is mainly dependent on the degree of the condensed packing of the magnetic dot lattice constant.

Using the molecular dynamic method we investigate numerically the current driven vortex motion in a superconducting film with periodic arrays of both ferromagnetic (FM) and anti-parallel ferromagnetic (AFM) dots. The simulation results show that in the absence of thermal fluctuation the vortex motion is dominated by the configurations of the magnetic dot array. This guided vortex motion is only observed at the onset of the depinning of the interstitial vortices. Two guided vortex motion mechanisms are discussed in this work. For the AFM configuration the vortex motion is mainly originated by the existence of magnetic dots with opposite magnetized moments, while for the FM case it is mainly dependent on the degree of the condensed packing of the magnetic dot lattice constant.

Due to quantum interference, light can transmit through dense atomic media, a phenomenon known as electromagnetically induced transparency (EIT). We propose that EIT is not limited to light transmission and there is an electronic analog where resonant transparency in charge transport in an opaque structure can be induced by electromagnetic radiation. A triple-quantum-dots system with K-type level structure is generally opaque due to the level in the center dot being significantly higher and therefore hopping from the left dot to the center dot is almost forbidden. We demonstrate that an electromagnetically induced electron transparency (EIET) in charge of transport can indeed occur in the K-type system. The direct evidence of EIET is that an electron can travel from the left dot to the right dot, while the center dot apparently becomes invisible. We analyze EIET and the related shot noise in both the zero and strong Coulomb blockade regimes. It is found that the EIET (position, height, and symmetry) can be tuned by several controllable parameters of the radiation fields, such as the Rabi frequencies and detuning frequencies. The result offers a transparency/ opaque tuning technique in charge transport using interfering radiation fields.

Using the molecular dynamic method we investigate numerically the current driven vortex motion in a superconducting film with periodic arrays of both ferromagnetic (FM) and anti-parallel ferromagnetic (AFM) dots. The simulation results show that in the absence of thermal fluctuation the vortex motion is dominated by the configurations of the magnetic dot array. This guided vortex motion is only observed at the onset of the depinning of the interstitial vortices. Two guided vortex motion mechanisms are discussed in this work. For the AFM configuration the vortex motion is mainly originated by the existence of magnetic dots with opposite magnetized moments, while for the FM case it is mainly dependent on the degree of the condensed packing of the magnetic dot lattice constant.

Using the molecular dynamic method we investigate numerically the current driven vortex motion in a superconducting film with periodic arrays of both ferromagnetic (FM) and anti-parallel ferromagnetic (AFM) dots. The simulation results show that in the absence of thermal fluctuation the vortex motion is dominated by the configurations of the magnetic dot array. This guided vortex motion is only observed at the onset of the depinning of the interstitial vortices. Two guided vortex motion mechanisms are discussed in this work. For the AFM configuration the vortex motion is mainly originated by the existence of magnetic dots with opposite magnetized moments, while for the FM case it is mainly dependent on the degree of the condensed packing of the magnetic dot lattice constant.

Fluorescent semiconductor quantum dots (QDs) have attracted tremendous attention over the last decade. The superior optical properties of QDs over conventional organic dyes make them attractive labels for a wide variety of biomedical applications, whereas their potential toxicity and instability in biological environment have puzzled scientific researchers. Much research effort has been devoted to surface modification and functionalization of QDs to make them versatile probes for biomedical applications, and significant progress has been made over the last several years. This review article aims to describe the current state-of-the-art of the synthesis, modification, bioconjugation, and applications of QDs for in vivo targeted imaging. In addition, QD-based multifunctional nanoprobes are also summarized.

Fluorescent semiconductor quantum dots (QDs) have attracted tremendous attention over the last decade. The superior optical properties of QDs over conventional organic dyes make them attractive labels for a wide variety of biomedical applications, whereas their potential toxicity and instability in biological environment have puzzled scientific researchers. Much research effort has been devoted to surface modification and functionalization of QDs to make them versatile probes for biomedical applications, and significant progress has been made over the last several years. This review article aims to describe the current state-of-the-art of the synthesis, modification, bioconjugation, and applications of QDs for in vivo targeted imaging. In addition, QD-based multifunctional nanoprobes are also summarized.

We report zinc stannate (ZTO) nanoneedles obtained through hydrothermal synthesis as a promising photoanode for CdS/CdSe quantum dot sensitized solar cells. The cell based on ZTO/CdS/CdSe with copper sulfide counter electrode recorded the highest conversion efficiency of 3.13% under 1 sun illumination with improved short-circuit current density of 18.96 mA cm2 and open-circuit photovoltage of 0.613 V which is several times higher than that of CdS sensitized ZTO cells. The high performance is attributed not only to large accumulation of photo-injected carriers but also to the slow process of recombination as one of the reasons for longer electron lifetime, which results in higher current density and open-circuit voltage, respectively.

We report zinc stannate (ZTO) nanoneedles obtained through hydrothermal synthesis as a promising photoanode for CdS/CdSe quantum dot sensitized solar cells. The cell based on ZTO/CdS/CdSe with copper sulfide counter electrode recorded the highest conversion efficiency of 3.13% under 1 sun illumination with improved short-circuit current density of 18.96 mA cm2 and open-circuit photovoltage of 0.613 V which is several times higher than that of CdS sensitized ZTO cells. The high performance is attributed not only to large accumulation of photo-injected carriers but also to the slow process of recombination as one of the reasons for longer electron lifetime, which results in higher current density and open-circuit voltage, respectively.

We report zinc stannate (ZTO) nanoneedles obtained through hydrothermal synthesis as a promising photoanode for CdS/CdSe quantum dot sensitized solar cells. The cell based on ZTO/CdS/CdSe with copper sulfide counter electrode recorded the highest conversion efficiency of 3.13% under 1 sun illumination with improved short-circuit current density of 18.96 mA cm2 and open-circuit photovoltage of 0.613 V which is several times higher than that of CdS sensitized ZTO cells. The high performance is attributed not only to large accumulation of photo-injected carriers but also to the slow process of recombination as one of the reasons for longer electron lifetime, which results in higher current density and open-circuit voltage, respectively.

We have investigated the role of linker molecules in quantum-dot-sensitized solar cells (QDSSCs) using density-functional theory (DFT) and experiments. Linkers not only govern the number of attached QDs but also influence charge separation, recombination, and transport. Understanding their behavior is therefore not straightforward. DFT calculations show that mercaptopropionic acid (MPA) and cysteine (Cys) exhibit characteristic binding configurations on TiO2 surfaces. This information is used to optimize the cell assembly process, yielding Cys-based cells that significantly outperform MPA cells, and reach power conversion efficiencies (PCE) as high as 2.7% under AM 1.5 illumination. Importantly, the structural information from theory also helps understand the cause for this improved performance.

Fluorescent semiconductor quantum dots (QDs) have attracted tremendous attention over the last decade. The superior optical properties of QDs over conventional organic dyes make them attractive labels for a wide variety of biomedical applications, whereas their potential toxicity and instability in biological environment have puzzled scientific researchers. Much research effort has been devoted to surface modification and functionalization of QDs to make them versatile probes for biomedical applications, and significant progress has been made over the last several years. This review article aims to describe the current state-of-the-art of the synthesis, modification, bioconjugation, and applications of QDs for in vivo targeted imaging. In addition, QD-based multifunctional nanoprobes are also summarized.

We report zinc stannate (ZTO) nanoneedles obtained through hydrothermal synthesis as a promising photoanode for CdS/CdSe quantum dot sensitized solar cells. The cell based on ZTO/CdS/CdSe with copper sulfide counter electrode recorded the highest conversion efficiency of 3.13% under 1 sun illumination with improved short-circuit current density of 18.96 mA cm2 and open-circuit photovoltage of 0.613 V which is several times higher than that of CdS sensitized ZTO cells. The high performance is attributed not only to large accumulation of photo-injected carriers but also to the slow process of recombination as one of the reasons for longer electron lifetime, which results in higher current density and open-circuit voltage, respectively.

Schools are often the first point of contact for young refugees resettling in Australia and play a significant role in establishing meaningful connections to Australian society and a sense of belonging in Australia (Olliff in Settling in: How do refugee young people fair within Australia's settlement system? Centre for Multicultural Youth Issues, Melbourne. http://www. cmyi. net. au/ResearchandPolicy. Accessed 21 June 2010, 2007; Gifford et al. in: Good Starts for recently arrived youth with refugee backgrounds: Promoting wellbeing in the first three years of settlement in Melbourne, Australia. Melbourne: La Trobe Refugee Research Centre. http://www. latrobe. edu. au/larrc/documents-larrc/reports/report-good-starts. pdf. Accessed 4 June 2011, 2009; Sidhu and Taylor in: Educational provision for refugee youth in Australia: Left to chance? Journal of Sociology,43(3), 283-300, 2007). However, too little is known of how refugee youth encounter school in their new country. This article draws upon individual narratives of young former refugee's experiences of high schools. It explores the stories told by the young people of being identified as different and of negotiating ways of belonging in schools both academically and socially. It argues that it is how the school positions the newly arrived refugee students within mainstream school culture that opens up or restricts opportunities for inclusion in all aspects of school (in culture and pedagogy).

We have investigated the role of linker molecules in quantum-dot-sensitized solar cells (QDSSCs) using density-functional theory (DFT) and experiments. Linkers not only govern the number of attached QDs but also influence charge separation, recombination, and transport. Understanding their behavior is therefore not straightforward. DFT calculations show that mercaptopropionic acid (MPA) and cysteine (Cys) exhibit characteristic binding configurations on TiO2 surfaces. This information is used to optimize the cell assembly process, yielding Cys-based cells that significantly outperform MPA cells, and reach power conversion efficiencies (PCE) as high as 2.7% under AM 1.5 illumination. Importantly, the structural information from theory also helps understand the cause for this improved performance.

Fluorescent semiconductor quantum dots (QDs) have attracted tremendous attention over the last decade. The superior optical properties of QDs over conventional organic dyes make them attractive labels for a wide variety of biomedical applications, whereas their potential toxicity and instability in biological environment have puzzled scientific researchers. Much research effort has been devoted to surface modification and functionalization of QDs to make them versatile probes for biomedical applications, and significant progress has been made over the last several years. This review article aims to describe the current state-of-the-art of the synthesis, modification, bioconjugation, and applications of QDs for in vivo targeted imaging. In addition, QD-based multifunctional nanoprobes are also summarized.

The impact of Förster resonant energy transfer (FRET) in CdTe quantum dot (QD) based photoelectrochemical cells is investigated. By deposition of different CdTe QD sizes onto indium on oxide electrodes, FRET across the photoactive film could be obtained, resulting in a 25% enhancement of the photon-to-current efficiency when compared to reference systems that lack FRET.

The impact of Förster resonant energy transfer (FRET) in CdTe quantum dot (QD) based photoelectrochemical cells is investigated. By deposition of different CdTe QD sizes onto indium on oxide electrodes, FRET across the photoactive film could be obtained, resulting in a 25% enhancement of the photon-to-current efficiency when compared to reference systems that lack FRET.

The impact of Förster resonant energy transfer (FRET) in CdTe quantum dot (QD) based photoelectrochemical cells is investigated. By deposition of different CdTe QD sizes onto indium on oxide electrodes, FRET across the photoactive film could be obtained, resulting in a 25% enhancement of the photon-to-current efficiency when compared to reference systems that lack FRET.

The impact of Förster resonant energy transfer (FRET) in CdTe quantum dot (QD) based photoelectrochemical cells is investigated. By deposition of different CdTe QD sizes onto indium on oxide electrodes, FRET across the photoactive film could be obtained, resulting in a 25% enhancement of the photon-to-current efficiency when compared to reference systems that lack FRET.

Amminelithium borohydride (LiBH4·NH3) is one of the most hydrogen-rich inorganic materials, showing potential application for hydrogen storage. In this paper, the dehydrogenation of LiBH4·NH3 was promoted significantly through heating in ammonia atmosphere which demonstrated that the coordinate between NH3 and LiBH4 is a crucial factor in inducing the hydrogen release for this system. Meanwhile, several metal hydrides LiH, NaH, and CaH2 were found to be effective in promoting the dehydrogenation of LiBH4·NH3. Among the studied additives, the effect of LiH, as an example, was discussed in detail. It was found that the promotion of dehydrogenation through LiH is due to the reaction: 3LiH + 3LiBH4·NH3 → Li4BN3H10 + 2LiBH4 + 3H2, releasing hydrogen from 60 °C.

Amminelithium borohydride (LiBH4·NH3) is one of the most hydrogen-rich inorganic materials, showing potential application for hydrogen storage. In this paper, the dehydrogenation of LiBH4·NH3 was promoted significantly through heating in ammonia atmosphere which demonstrated that the coordinate between NH3 and LiBH4 is a crucial factor in inducing the hydrogen release for this system. Meanwhile, several metal hydrides LiH, NaH, and CaH2 were found to be effective in promoting the dehydrogenation of LiBH4·NH3. Among the studied additives, the effect of LiH, as an example, was discussed in detail. It was found that the promotion of dehydrogenation through LiH is due to the reaction: 3LiH + 3LiBH4·NH3 → Li4BN3H10 + 2LiBH4 + 3H2, releasing hydrogen from 60 °C.

Amminelithium borohydride (LiBH4·NH3) is one of the most hydrogen-rich inorganic materials, showing potential application for hydrogen storage. In this paper, the dehydrogenation of LiBH4·NH3 was promoted significantly through heating in ammonia atmosphere which demonstrated that the coordinate between NH3 and LiBH4 is a crucial factor in inducing the hydrogen release for this system. Meanwhile, several metal hydrides LiH, NaH, and CaH2 were found to be effective in promoting the dehydrogenation of LiBH4·NH3. Among the studied additives, the effect of LiH, as an example, was discussed in detail. It was found that the promotion of dehydrogenation through LiH is due to the reaction: 3LiH + 3LiBH4·NH3 → Li4BN3H10 + 2LiBH4 + 3H2, releasing hydrogen from 60 °C.

Amminelithium borohydride (LiBH4·NH3) is one of the most hydrogen-rich inorganic materials, showing potential application for hydrogen storage. In this paper, the dehydrogenation of LiBH4·NH3 was promoted significantly through heating in ammonia atmosphere which demonstrated that the coordinate between NH3 and LiBH4 is a crucial factor in inducing the hydrogen release for this system. Meanwhile, several metal hydrides LiH, NaH, and CaH2 were found to be effective in promoting the dehydrogenation of LiBH4·NH3. Among the studied additives, the effect of LiH, as an example, was discussed in detail. It was found that the promotion of dehydrogenation through LiH is due to the reaction: 3LiH + 3LiBH4·NH3 → Li4BN3H10 + 2LiBH4 + 3H2, releasing hydrogen from 60 °C.

Three experiments examined the effects of image decorrelation on the stereoscopic detection of sinusoidal depth gratings in static anddynamic random-dot stereograms (RDS). Detection was found to tolerate greater levels of image decorrelation as: (i) density increasedfrom 23 to 676 dots/deg2; (ii) spatial frequency decreased from 0.88 to 0.22 cpd; (iii) amplitude increased above 0.5 arcmin; and (iv) dotlifetime decreased from 1.6 s (static RDS) to 80 ms (dynamic RDS). In each case, the specific pattern of tolerance to decorrelation couldbe explained by its consequences for image sampling, filtering, and the influence of depth noise.

Three experiments examined the effects of image decorrelation on the stereoscopic detection of sinusoidal depth gratings in static anddynamic random-dot stereograms (RDS). Detection was found to tolerate greater levels of image decorrelation as: (i) density increasedfrom 23 to 676 dots/deg2; (ii) spatial frequency decreased from 0.88 to 0.22 cpd; (iii) amplitude increased above 0.5 arcmin; and (iv) dotlifetime decreased from 1.6 s (static RDS) to 80 ms (dynamic RDS). In each case, the specific pattern of tolerance to decorrelation couldbe explained by its consequences for image sampling, filtering, and the influence of depth noise.

Three experiments examined the effects of image decorrelation on the stereoscopic detection of sinusoidal depth gratings in static anddynamic random-dot stereograms (RDS). Detection was found to tolerate greater levels of image decorrelation as: (i) density increasedfrom 23 to 676 dots/deg2; (ii) spatial frequency decreased from 0.88 to 0.22 cpd; (iii) amplitude increased above 0.5 arcmin; and (iv) dotlifetime decreased from 1.6 s (static RDS) to 80 ms (dynamic RDS). In each case, the specific pattern of tolerance to decorrelation couldbe explained by its consequences for image sampling, filtering, and the influence of depth noise.