A5044898123- Perovskite Materials and Applications
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Inorganic Chemistry and Materials
- Conducting polymers and applications
- MXene and MAX Phase Materials
- 2D Materials and Applications
- Electronic and Structural Properties of Oxides
- Thermal Expansion and Ionic Conductivity
- Solid-state spectroscopy and crystallography
- Metal and Thin Film Mechanics
- Crystallography and molecular interactions
- Organic Electronics and Photovoltaics
- Advanced Photocatalysis Techniques
- Layered Double Hydroxides Synthesis and Applications
Center for NanoScience
2020-2023
Ludwig-Maximilians-Universität München
2018-2023
Abstract Since their introduction in 2017, the efficiency of lead‐free halide perovskite solar cells based on Cs 2 AgBiBr 6 has not exceeded 3%. The limiting bottlenecks are attributed to a low electron diffusion length, self‐trapping events and poor selectivity contacts, leading large non‐radiative V OC losses. Here, 2D/3D hybrid double perovskites introduced for first time, using phenethyl ammonium as constituting cation. resulting show an increased up 2.5% champion 2.03% average, marking...
Abstract Two‐dimensional (2D) hybrid double perovskites are a promising emerging class of materials featuring superior intrinsic and extrinsic stability over their 3D parent structures, while enabling additional structural diversity tunability. Here, we expand the Ag–Bi‐based perovskite system, comparing structures obtained with halides chloride, bromide, iodide organic spacer cation 4‐fluorophenethylammonium (4FPEA) to form n = 1 Ruddlesden–Popper (RP) phases 4 AgBi X 8 ( Cl, Br, I). We...
Passivation is one of the most promising concepts to heal defects created at surface and grain boundaries polycrystalline perovskite thin films, which significantly deteriorate photovoltaic performance stability corresponding devices. Here, 1,10-phenanthroline, known as a bidentate chelating ligand, implemented between methylammonium lead iodide (MAPbI3) film hole-transport layer for both passivating lead-based (undercoordinated ions) converting excess/unreacted (PbI2) buried interfaces,...
Lead‐free double perovskites have attracted much attention as possible alternatives to lead halide based in photovoltaic applications. However, date only few been successfully employed optoelectronic device prototypes. Therefore, the search for stable and lead‐free materials is ongoing. Here, we present successful growth of high‐quality Cs 2 NaFeCl 6 single crystals their temperature‐dependent structural optical properties. By combining electron paramagnetic resonance (EPR), crystal...
Abstract The presence of lead in novel hybrid perovskite-based solar cells remains a significant issue regarding commercial applications. Therefore, antimony-based perovskite-like A 3 M 2 X 9 structures are promising new candidates for low toxicity photovoltaic So far, MA Sb I was reported to only crystallize the ‘zero-dimensional’ (0D) dimer structure with wide indirect bandgap properties. However, formation 2D layered polymorph is more suitable cell applications due its expected direct and...
In the search for lead-free perovskites, silver pnictohalides recently gained attention as novel perovskite-inspired materials photovoltaics due to their high stability, low toxicity, and promising early efficiencies, especially indoor applications. Recent research on such "rudorffites" mainly addresses bismuth iodides (Ag–Bi–I), while antimony analogues are hardly investigated intrinsic challenges in synthesis of Sb-based thin films. Here, we establish a synthetic route prepare Ag–Sb–I...
Abstract Advancing the attainable composition space of a compound class can lead to fascinating materials. The first tetravalent metal nitridophosphate, namely Hf 9−x P 24 N 52−4x O 4x (x≈1.84), was prepared by high‐pressure metathesis. Group 4 nitridophosphates are now an accessible compounds. metathesis reaction using multianvil setup yielded single crystals that were suitable for structure analysis. Magnetic properties indicate in oxidation state +IV. Optical measurements show band gap UV...
Heteroatom alloying of lead-free perovskite derivatives is a highly promising route to tailor their optoelectronic properties and stability for multiple applications. Here, we demonstrate the facile solution-based synthesis Sn-alloyed layered MA3Sb2I9 thin films by precursor engineering, combining acetate halide salts. An increasing concentration tin halides in different oxidation states leads strong boost absorption over whole visible spectrum. We phase-pure elucidate heterovalent...
Abstract Advancing the attainable composition space of a compound class can lead to fascinating materials. The first tetravalent metal nitridophosphate, namely Hf 9−x P 24 N 52−4x O 4x (x≈1.84), was prepared by high‐pressure metathesis. Group 4 nitridophosphates are now an accessible compounds. metathesis reaction using multianvil setup yielded single crystals that were suitable for structure analysis. Magnetic properties indicate in oxidation state +IV. Optical measurements show band gap UV...
We describe the oxonitridophosphates M1- xPO3+4 xN1-4 x ( ≈ 0.05) and isotypic oxophosphates M0.75PO4 M = Zr, Hf) obtained by high-pressure metathesis. The structures (ZrSiO4-type, space group I41/ amd (no. 141), a 6.5335(7)-6.6178(12), c 5.7699(7)-5.8409(9) Å, Z 4) were refined from single-crystal X-ray diffraction data, powder samples examined with quantitative Rietveld refinement. Infrared spectroscopy did not indicate presence of X-H X O, N) bonds. optical band gaps, between 3.5 4.3 eV,...