1. Lattice-matched ▫$Ta_3N_5/Nb_5N_6$▫ interface enables a bulk charge separation efficiency of close to 100%Yitong Liu, Zeyu Fan, Ronghua Li, Andraž Mavrič, Iztok Arčon, Matjaž Valant, Gregor Kapun, Beibei Zhang, Chao Feng, Zemin Zhang, 2025, original scientific article Abstract: The interface between the semiconductor light absorber
and the metal electrode is critical for facilitating the extraction of photogenerated charges in photoelectrodes. Achieving a lattice-matched
semiconductor/electrode interface with low defect density is highly desirable but remains a challenge for Ta3N5 photoanodes. In this study, we synthesized niobium nitride thin film electrodes with controllable crystallographic phases to achieve a lattice-matched Ta3N5/Nb5N6 back contact. This results in an enhanced crystallinity of the Ta3N5 film and
reduced interfacial defect density. Consequently, the photoanode with the lattice-matched back contact attains a record half-cell solar-to-hydrogen conversion efficiency of 4.1%, attributed to the bulk carrier separation efficiency of nearly 100%. This work highlights lattice-matching as an effective strategy to enhance the efficiency of thin film-based solar energy conversion devices.
Keywords: photoelectrochemistry, photoanode, interface, semiconductors
Published in RUNG: 28.03.2025; Views: 472; Downloads: 8
 Link to file
This document has many files! More... |
2. Surface acidity and basicity of ZnAlGaOx catalysts supportsLaura Milišić, Blaž Belec, Anja Siher, Gregor Žerjav, Albin Pintar, Andraž Mavrič, 2025, published scientific conference contribution abstract Keywords: surface acidity, surface basicity, ZnAlGaOx catalysts, layered double hydroxide, pyridine temperature-programmed desorption, TPD
Published in RUNG: 20.03.2025; Views: 468; Downloads: 2
Link to file
This document has many files! More... |
3. Beyond surface area : enhanced pseudocapacitive properties of cobalt layered double hydroxide through structural modificationsAnja Siher, Ksenija Maver, Uroš Luin, Albin Pintar, Iztok Arčon, Andraž Mavrič, 2025, original scientific article Abstract: Cobalt hydroxide and other first-row transition metal hydroxides have gained significant attention as pseudocapacitor materials due to their rapid and reversible redox processes. Their layered structures facilitate interactions between electrolyte anions and cobalt cation sites within the bulk of the material, enabling higher charge density and extending redox activity beyond the particle surface. By controlled precipitation under hydrothermal conditions, the structure and morphology of cobalt hydroxides can be optimized to enhance electrochemical performance. Challenging conventional assumptions, surface area alone is not the primary factor driving increased pseudocapacitive performance. The hexagonal hydrotalcite-like structure, characterized by lower skeletal density and larger basal plane spacing, outperforms the monoclinic cobalt carbonate hydroxide structure, achieving an order of magnitude higher capacitance. In situ X-ray absorption spectroscopy provides critical insights into the pseudocapacitive behavior, revealing enhanced accessibility of Co2+ sites for electrochemical oxidation. While monoclinic cobalt carbonate hydroxide exhibits minimal changes in the Co2+ oxidation state, indicative of surface-limited redox activity, the hydrotalcite-like cobalt hydroxides show substantial shifts in the Co K-edge position, highlighting oxidation of Co2+ sites throughout the bulk.
Keywords: pseudocapacitors, layered-double hydroxides, cobalt hydroxide, redox processes, in situ x-ray absorption spectroscopy
Published in RUNG: 14.03.2025; Views: 636; Downloads: 7
 Full text (1,48 MB)
This document has many files! More... |
4. |
5. |
6. First utilization of magnetically-assisted photocatalytic iron ▫$oxide-TiO_2$▫ nanocomposites for the degradation of the problematic antibiotic ciprofloxacin in an aqueous environmentJosip Radić, Gregor Žerjav, Lucija Jurko, Perica Bošković, Lidija Fras Zemljič, Alenka Vesel, Andraž Mavrič, Martina Gudelj, Olivija Plohl, 2024, original scientific article Abstract: The emergence of antimicrobial resistance due to antibiotics in the environment presents significant public health, economic, and societal risks. This study addresses the need for effective strategies to reduce antibiotic residues, focusing on ciprofloxacin degradation. Magnetic iron oxide nanoparticles (IO NPs), approximately 13 nm in size, were synthesized and functionalized with branched polyethyleneimine (bPEI) to obtain a positive charge. These IO-bPEI NPs were combined with negatively charged titanium dioxide NPs (TiO2@CA) to form magnetically photocatalytic IO-TiO2 nanocomposites. Characterization techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), electrokinetic measurements, and a vibrating sample magnetometer (VSM), confirmed the successful formation and properties of the nanocomposites. The nanocomposites exhibited a high specific surface area, reduced mobility of photogenerated charge carriers, and enhanced photocatalytic properties. Testing the photocatalytic potential of IO-TiO2 with ciprofloxacin in water under UV-B light achieved up to 70% degradation in 150 min, with a degradation rate of 0.0063 min−1. The nanocomposite was magnetically removed after photocatalysis and successfully regenerated for reuse. These findings highlight the potential of IO-TiO2 nanocomposites for reducing ciprofloxacin levels in wastewater, helping curb antibiotic resistance.
Keywords: photocatalytic degradation, magnetic iron oxide-TiO2 nanocomposites, hetero-agglomeration, multifunctionality, antibiotic ciprofloxacin, antimicrobial resistance
Published in RUNG: 09.09.2024; Views: 1345; Downloads: 6
Full text (14,48 MB)
This document has many files! More... |
7. Transparent vanadium doped titania-silica films : structural characterization and self-cleaning propertiesAndraž Šuligoj, Nejc Povirk, Ksenija Maver, Andraž Mavrič, Urška Lavrenčič Štangar, Angelja Kjara Surca, 2024, original scientific article Keywords: photocatalysis, TiO2-SiO2, vanadium, film, Raman spectroscopy
Published in RUNG: 09.09.2024; Views: 1223; Downloads: 7
Full text (9,47 MB)
This document has many files! More... |
8. Understanding the in-situ transformation of ▫$Cu_xO$▫ interlayers to increase the water splitting efficiency in NiO/n-Si photoanodesChao Feng, Zhi Liu, Huanxin Ju, Andraž Mavrič, Matjaž Valant, Jie Fu, Beibei Zhang, Yanbo Li, 2024, original scientific article Abstract: The buried interface tens of nanometers beneath the solid-liquid junction is crucial for photocarrier extraction, influencing the overall efficiency of photoelectrochemical devices. Precise characterization of the interfacial properties is essential for device optimization but remains challenging. Here, we directly probe the in situ transformation of a CuxO interlayer at the NiO/n-Si interface by hard X-ray photoelectron spectroscopy. It is found that Cu(I) in the CuxO interlayer gradually transforms to Cu(II) with air exposure, forming an energetically more favorable interface and improving photoanode’s efficiency. Based on this finding, a reactive e-beam evaporation process is developed for the direct deposition of a CuO interlayer, achieving a half-cell solar-to-hydrogen efficiency of 4.56% for the optimized NiO/CuO/n-Si heterojunction photoanode. Our results highlight the importance of precision characterization of interfacial properties with advanced hard X-ray photoelectron spectroscopy in guiding the design of efficient solar water-splitting devices.
Keywords: photo anode, energy harvesting, nickel oxide, interface
Published in RUNG: 01.08.2024; Views: 2136; Downloads: 12
Full text (2,10 MB)
This document has many files! More... |
9. Tunable emissive ▫$CsPbBr_3 /Cs_4PbBr_6$▫ quantum dots engineered by discrete phase transformation for enhanced photogating in field-effect phototransistorsHan Xiao, Siyuan Wan, Lin He, Junlong Zou, Andraž Mavrič, Yixi Wang, Marek Piotrowski, Anil Kumar Bandela, Paolo Samorì, Zhiming M. Wang, 2024, original scientific article Abstract: Precise control of quantum structures in hybrid nanocrystals requires advancements in scientific methodologies. Here, on the design of tunable CsPbBr3/Cs4PbBr6 quantum dots are reported by developing a unique discrete phase transformation approach in Cs4PbBr6 nanocrystals. Unlike conventional hybrid systems that emit solely in the green region, this current strategy produces adjustable luminescence in the blue (450 nm), cyan (480 nm), and green (510 nm) regions with high photoluminescence quantum yields up to 45%, 60%, and 85%, respectively. Concentration‐dependent studies reveal that phase transformation mechanisms and the factors that drive CsBr removal occur at lower dilutions while the dissolution–recrystallization process dominates at higher dilutions. When the polymer‐CsPbBr3/Cs4PbBr6 integrated into a field‐effected transistor the resulting phototransistors featured enhanced photosensitivity exceeding 105, being the highest reported for an n‐type phototransistor, while maintaining good transistor performances as compared to devices consisting of polymer‐CsPbBr3 NCs.
Keywords: crystallization mechanisms, dilution-induced kinetic trapping, photogating effect, phototransistors, quantum dots
Published in RUNG: 26.06.2024; Views: 1622; Downloads: 12
Full text (4,02 MB)
This document has many files! More... |
10. |
