Quantum dot solar cells (QDSC) are an emerging field in solar cell research that uses quantum dots as the photovoltaic material, as opposed to better-known bulk semi-conductive materials such as silicon. Quantum dots have tunable band-gaps across a wide range of energy levels by changing the quantum dot size. This property makes quantum dots attractive for multi-junction solar cells, where a variety of different energy levels are used to extract more energy from the solar spectrum. A robust S2-/S(n)2- electrolyte was specifically designed for compatibility with CdSe quantum dots in solar cells. The new pyrrolidinium ionic liquid reaches 1.86 % efficiency and short-circuit current close to 14 mA cm-2 under air-mass 1.5 global illumination, and improves the device lifetime with good photoanode stability over 240 hours. Photovoltaic characterization shows that the solar cell limitations relate to poor catalysis of regeneration at the counter electrode and high recombination. Further improvement of these factors in the robust electrolyte configuration may thus have a significant impact for advancing the state-of-art of QDSCs. Such an electrolyte may also be used in developing some other, for example, chemical sensing materials.
COBISS.SI-ID: 4863258
A mechanistic study to provide diagnostics of anodic stripping electrode processes at bismuth-film electrodes is presented from both theoretical and experimental points of view. Theoretical models for three types of electrode mechanisms are developed under conditions of square-wave voltammetry. In the course of the deposition step, it has been assumed that a uniform film of the metal analyte is formed on the bismuth substrate, in-situ deposited onto a glassy carbon electrode surface, without considering mass transfer within either the bismuth or the metal analyte film. Theoretical data are analyzed in terms of dimensionless critical parameters related with electrode kinetics, mass transfer, adsorption equilibria, and possible lateral interactions within the deposited metal particles. Theoretical analysis enables definition of simple criteria for differentiation and characterization of electrode processes. Comparing theoretical and experimental data, anodic stripping processes of zinc(II), cadmium(II), and lead(II) are successfully characterized, revealing significant differences in their reaction pathways. The proposed easy-to-perform diagnostic route is considered to be of a general use while the bismuth-film exploited in this study served as a convenient non-mercury model substrate surface.
COBISS.SI-ID: 4942874
We developed a mathematical model, and ensuing software, for process simulation of the elemental imaging using hyphenated technique laser ablation - elemental mass spectrometry (LA-ICP-MS) based on virtual imaging of a digital image of the sample. This allows optimization of all major instrumental settings for generation of high-quality element maps prior to the actual experiment. In this way damage to often unique and precious samples is avoided, whereas the analysis time and costs are significantly minimized. The achievement places us among leading groups in this field.
COBISS.SI-ID: 4547610
The article outlines the mathematical modelling of the leaching profiles of some elements (B, Cd, Co, Mn, Ni, and Sr) from soils from Cornwall, UK, when exposed to an artificial gastric solution. The modelling allowed the quantification of the influence of liquid film diffusion and apparent solid phase diffusion on the liability of the elements upon ingestion.
COBISS.SI-ID: 4448538
A novel and recyclable synthetic method using an ionic liquid as a green solvent was developed for synthesis of ecocomposite materials from cellulose (CEL) and chitosan (CS). Adding CEL into CS substantially increases tensile strength of the composite while entirely retaining the adsorbing properties of CS. The composite is much better adsorbent for microcystin than other materials used for removal of cyanotoxins from water. It can adsorb four times more microcystin compared to the best known adsorbent. The composite can be reused because adsorbed microcystin can be desorbed quantitatively.
COBISS.SI-ID: 2702075