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A Comprehensive Case Study of a Full Size BIPV Facade
Get PDFBuilding integrated photovoltaic BIPV systems present a promising avenue for integrating renewable energy generation into urban environments. However, they pose unique challenges, including higher planning efforts and reduced yield generation compared to conventional rooftop systems. Despite these challenges, the double use of area and the high potential in urban landscapes offer compelling advantages. Modules have become highly customizable to fit architect s requirements in sustainable yet also aesthetic building material. This paper discusses the results of a living laboratory in Berlin, which is both a typical building with a ventilated curtain wall and a unique showcase for BIPV technology. Through careful analysis of various factors, including module positioning, ventilation, and shading, this study demonstrates the feasibility and practicality of BIPV integration. The living lab not only highlights the technical viability of BIPV systems but also underscores their potential to enhance architectural aesthetics and promote sustainability and carbon neutrality in urban landscape
Metalloradical driven enzymatic CO2 reduction by a dynamic Ni Fe cluster
No full textCarbon monoxide dehydrogenases CODHs selectively catalyse the reversible reduction of CO2 to CO and water. The catalytic centre of CODHs contains a unique [NiFe4 OH 3 S 4] cluster whose role in activating and converting CO2 is poorly understood. Here we reveal the structures of all catalytically relevant oxidation states with and without substrates and products bound. We show that the Ni Fe cluster combines a rigid Fe S core with a dynamic Ni I II Fe II dyad. The redox active element is the Ni ion, cycling between square planar Ni II and T shaped Ni I states with metalloradical character, the latter serving as the nucleophile for CO2 activation. The Fe II ion switches between two positions, the one preceding CO2 activation is close to Ni I with a potential Ni I Fe II interaction and the other binds the substrates CO2 and water. We demonstrate how the Ni Fe cluster creates an efficient CO2 reduction catalyst and provides a blueprint for the design of novel catalysts based on abundant transition metal
The structural basis of aldo keto reductase 1C3 inhibition by 17 alpha picolyl and 17 E picolinylidene androstane derivatives
No full textHuman aldo keto reductase 1C3 AKR1C3 is a steroid modifying enzyme involved in cancer progression. Here, A ring modified 17 amp; 945; picolyl and 17 E picolinylidene androstane derivatives are shown to inhibit AKR1C3 activity in vitro. None of the androstane derivatives have off target affinity for the androgen receptor, based on a fluorescence assay in yeast cells. The X ray structure of AKR1C3 in complex with the strongest inhibitor, a 17 amp; 945; picolyl androstane with a C3 oxime modification, was determined at 1.7 amp; 8201; resolution. Based on this crystal structure and molecular docking, inhibition of AKR1C3 by the 17 amp; 945; picolyl or 17 E picolinylidene derivatives depends on interactions between the C3 modification and the NADP cofactor, while the C17 amp; 945; picolyl or C17 picolinylidene group anchors the inhibitor to AKR1C3. Because one AKR1C3 inhibitor identified here was also previously reported to inhibit CYP17, it may be possible for future researchers to design dual AKR1C3 CYP17 inhibitors based on a steroid scaffold for potential treatment of advanced prostate cancer
Novel Precursor for h BN Synthesis on Ni 111 Substrates
Get PDFIn this study, we report the synthesis of single crystalline h BN on Ni 111 under ultrahigh vacuum UHV conditions using hexamethylborazine HMB as a nonclassical precursor. The novel use of HMB facilitates the diffusion of methyl groups into the bulk of Ni 111 , playing a critical role in the achievement of high quality crystalline h BN layers. The synthesis is performed on a 2 mm thick Ni 111 single crystal and on a 2 amp; 956;m thick Ni 111 thin film on sapphire to evaluate the feasibility of synthesizing h BN on industrially relevant substrates. Advanced microscopic and spectroscopic techniques confirm the successful synthesis of h BN. The growth of h BN was investigated by scanning tunneling microscopy and low energy electron microscopy. Low energy electron diffraction confirms the single crystallinity of the grown 2 dimensional layer. X ray photoelectron spectroscopy confirms the presence of boron and nitrogen bonds at the same binding energies reported in the literature for h BN. In contrast, photoemission electron microscopy allows identification of the presence of h BN throughout the Ni 111 surface. This work advances the understanding of h BN growth mechanisms on metal substrates and provides a foundation for improving synthesis methods to meet the demands of next generation materials and device
Plasmon Mediated Hybridization of Wannier Mott and Frenkel Excitons in a Monolayer WS2 J Aggregate Hybrid System
Get PDFA tunable plasmonic platform that allows room temperature hybridization of dissimilar excitons, namely of Wannier Mott excitons in monolayer 1L WS2 and Frenkel excitons in molecular J aggregates via simultaneous strong coupling SC to surface plasmon polaritons, is presented. It is based on a simple layered design consisting of a thin planar silver film and a dielectric spacer on which monolayer and the aggregates are assembled. SC is revealed by angle dependent spectroscopic ellipsometry measurements in total internal reflection geometry by the observation of double Rabi splitting at the two excitonic resonances. The exciton exciton plasmon system is analyzed with the coupled oscillator model, and modulation of polariton character and dynamics by the number of molecules participating in the coupling is demonstrated. Furthermore, a route is proposed to remotely control the mode splitting at the Frenkel excitonic resonance via electrostatic gating of the 1L WS2 and to switch the molecule plasmon interaction between the weak and SC regim
Local Fermi Level Engineering in 2D MoS2 Realized via Microcontact Printing of Self Assembled Monolayers for Next Generation Electronics
Get PDFSilicon based technology is approaching scalability limits due to severe short channel effects arising from its intrinsic bulk properties. In contrast, two dimensional 2D transition metal dichalcogenides TMDCs exhibit remarkable resilience to these effects because of their atomic scale thickness, positioning them as promising candidates for next generation optical and electronic devices. However, realizing 2D material based technology still requires the development of local p and n type doping methods essential for complementary circuits. Self assembled monolayers SAMs have shown the ability to locally engineer electronic energy levels in 2D TMDCs to address this challenge. In this study, we demonstrate local engineering of electronic energy levels on micrometer scale in semiconducting single layer 1L MoS2 by patterning the supporting substrate with functional SAMs via microcontact printing CP . Three SAMs were selected two with large opposing dipole moments and one non dipolar reference. Their impact on surface properties particularly the work function and on optoelectronic properties of 1L MoS2 was investigated via Kelvin probe microscopy and photoluminescence PL mapping. Significant shifts in work function and PL were observed. FETs fabricated on locally patterned substrates enabled direct comparison, confirming that threshold voltage shifts up to 80 V and ON current increases by two orders of magnitude arise solely from SAM polarity. This work demonstrates that CP and the electrostatic doping capabilities of dipolar SAMs offer a straight forward and scalable approach to locally engineering 1L MoS2 energy level
Correlative electrochemical and spectroscopic study of the surface reconstruction and the oxygen evolution reaction on structure and morphology directed nickel oxides
No full textFirst Principles Studies on the Structure and Stability of the Solid Electrolyte Interphase with LiPON in Solid State Batteries
Get PDFThe formation of a solid electrolyte interphase SEI resulting from the decomposition of the solid electrolyte in contact with an alkali metal significantly influences battery performance. Despite extensive research on the SEI s chemical composition and distribution, its atomic level structure and stability remain poorly understood. This study employs first principles calculations to investigate the stability of all possible interfaces formed during the decomposition of lithium phosphorus oxynitride LiPON upon contact with lithium metal. A systematic analysis identified the following interfacial stability sequence Li2O Li3N gt; Li2O Li3P Li2O Li3PO4 gt; Li2O 1D LiPON. Interestingly, for interfaces involving solely Li3N, the observed trend is Li3N Li3P gt; Li3N Li3PO4 gt; Li3N 1D LiPON. Additionally, Li3P based interfaces exhibit a trend of Li3P Li3PO4 gt; Li3P 1D LiPON. These results suggest that the SEI between LiPON and lithium metal exhibits a distribution composed of Li Li2O Li3N Li3P Li3PO4 LiPON. This systematic analysis offers valuable insights into the relative stability of interfaces formed between LiPON decomposition products and lithium metal, potentially paving the way for improved stability and performance in lithium based battery system
Influence of Capillary s Surface Scattering for Small Angle X Ray Scattering Measurements
No full textMark tubes are commonly used as capillaries for high precision small wide angle X ray scattering SAXS WAXS measurements. For empty capillaries made of fused silica and borosilicate glass, an anisotropic, intensity varying, and position dependent contribution of scatter has been observed. This contribution increases from the bulk scatter level with decreasing q value for q amp; 8201; amp; 10885; amp; 8201;0.3 amp; 8201;nm amp; 8722;1. Surface scattering from nanostructures is thought to be the cause of this effect. These are created by the thermal forming processes from the bulk glasses. SAXS WAXS, micro computed tomography, atomic force microscopy scattering type scanning near field microscope, scanning electron microscope energy dispersive X ray spectroscopy, and dark field light microscopic images are taken to qualify commercially available Mark tubes. In an intensive comparison with the literature of known surface structuring effects during the processing of fused silica and borosilicate glass, conclusions are drawn about their formation during the individual steps of the manufacturing process. As a result, a model for q amp; 8201; amp; 8776; amp; 8201;0 17 amp; 8201;nm amp; 8722;1 is given to describe the scattering background and a possibility to reduce the surface scattering. This would enable the measurement of nanoparticles with SAXS at a lower concentration, or lower contrast, and with the same radiation dos
Generalizations of Pseudo Majorana Functional Renormalization Group and its Application to Highly Frustrated Spin Systems
No full textSpin systems are known for their purely interacting nature, causing them to lack a canonical perturbative limit, which usually helps to understand the fundamental physics of a system. A method that has proven effective for the description of strongly correlated systems is Functional Renormalization Group FRG , which can be thought of as an alternative to the path integral formalism as an approach to many body quantum mechanics. The basic concept is to cure infrared divergences by introducing a cutoff to correlation functions. Continuously lowering the infrared cutoff and hence allowing the system to occupy lower lying energy states is called the FRG flow and is formulated in terms of differential equations. The solutions to these equations are functions which describe effective interactions between particles and hence contain information about particle correlations and thermodynamic quantities. Formulating FRG in terms of spins turns out to be a subtle endeavor, though, as the spin algebra relations are relatively complicated compared to, for example, the canonical anti commutation relations of fermions. In order to use the advantages of FRG for spin systems, one can map spins onto fermionic operators, which leads to pseudo fermion FRG PFFRG , developed by Reuther and Wölfle.[198] Alter natively, one can express spins in terms of Majorana operators, leading to pseudo Majorana FRG PMFRG , which has been developed by Niggemann, Sbierski, and Reuther.[163] PMFRG is particularly powerful at finite temperatures, where useful properties of Majorana operators render the method more accurate than PFFRG. In contrast to many other methods, PFFRG and PMFRG are applicable to any spin system, even frustrated ones. In this work, PMFRG is being generalized and applied to highly frustrated spin systems. In particular, spin representations in terms of Majorana operators for spins with arbitrary large spin magnitude S are being investigated and classified thoroughly, which closes a gap in the literature about the second quantization of spin operators. Moreover, it is presented how to generalize PMFRG for Heisenberg models with full SU 2 symmetry to XXZ models exhibiting only a U 1 symmetry. This opens up a wide range of interesting applications for PMFRG. An example is the XXZ model on the pyrochlore lattice, which is known to exhibit conventional long range order but also exotic spin liquid ground states in the so called spin ice phase. PMFRG is applied to this model, and the results are being compared to experiments. Furthermore, the entire phase diagram of the XXZ model is being mapped out. Also, the capability of PMFRG to reproduce low energy field theory predictions and to determine critical exponents is being teste