Owing to their large ratio of surface area to mass and volume, metal-organic frameworks and porous carbons have revolutionized many applications that rely on chemical and physical interactions at ...surfaces. However, a major challenge today is to shape these porous materials to translate their enhanced performance from the laboratory into macroscopic real-world applications. In this review, we give a comprehensive overview of how the precise morphology control of metal oxides can be transferred to metal-organic frameworks and porous carbon materials. As such, tailored material structures can be designed in 0D, 1D, 2D, and 3D with considerable implications for applications such as in energy storage, catalysis and nanomedicine. Therefore, we predict that major research advances in morphology control of metal-organic frameworks and porous carbons will facilitate the use of these materials in addressing major needs of the society, especially the grand challenges of energy, health, and environment.
We give a comprehensive overview of how the morphology control is an effective and versatile way to control the physicochemical properties of metal oxides that can be transferred to metal-organic frameworks and porous carbon materials.
The development of metal‐organic frameworks (MOFs) has had a significant impact on various fields of chemistry and materials science. Naturally, polymer science also exploited this novel type of ...material for various purposes, which is due to the defined porosity, high surface area, and catalytic activity of MOFs. The present review covers various topics of MOF/polymer research beginning with MOF‐based polymerization catalysis. Furthermore, polymerization inside MOF pores as well as polymerization of MOF ligands is described, which have a significant effect on polymer structures. Finally, MOF/polymer hybrid and composite materials are highlighted, encompassing a range of material classes, like bulk materials, membranes, and dispersed materials. In the course of the review, various applications of MOF/polymer combinations are discussed (e.g., adsorption, gas separation, drug delivery, catalysis, organic electronics, and stimuli‐responsive materials). Finally, past research is concluded and an outlook toward future development is provided.
The combination of metal‐organic frameworks (MOFs) and polymers in various fields of research is highlighted. MOF‐governed polymerization catalysis and MOFs as a polymerization environment are covered, and the work on MOF/polymer composites and hybrid materials with respect to bulk materials, membranes, and dispersed materials are presented.
The photocatalytic CO2 reduction reaction (CRR) represents a promising route for the clean utilization of stranded renewable resources, but poor selectivity resulting from the competing hydrogen ...evolution reaction (HER) in aqueous solution limits its practical applicability. In the present contribution a photocatalyst with hydrophobic surfaces was fabricated. It facilitates an efficient three‐phase contact of CO2 (gas), H2O (liquid), and catalyst (solid). Thus, concentrated CO2 molecules in the gas phase contact the catalyst surface directly, and can overcome the mass‐transfer limitations of CO2, inhibit the HER because of lowering proton contacts, and overall enhance the CRR. Even when loaded with platinum nanoparticles, one of the most efficient HER promotion cocatalysts, the three‐phase photocatalyst maintains a selectivity of 87.9 %. Overall, three‐phase photocatalysis provides a general and reliable method to enhance the competitiveness of the CRR.
A photocatalytic CO2 reduction reaction (CRR) in aqueous solution is a promising reaction route, while severe H2 generation (HER) greatly limits its selectivity and activity. A strategy to obtain a three‐phase contact of CO2 (gas), H2O (liquid) and catalyst (solid) is described to overcome the mass transfer limitation of CO2, elevate the CO2 concentration on the catalyst surface, restrain the HER, and enhance the activity and selectivity of the CRR.
Battery storage systems can balance the intermittency of renewable energy sources. Lithium-ion systems exhibit a declining price trajectory alongside a growing demand. However, little is known about ...consumer preferences and appropriate business models for storage systems. This paper presents an analysis of German adopters of a photovoltaic system (n = 752) and interested non-adopters (n = 84) to investigate their preferences for lithium-ion storage systems. In a choice experiment respondents had to choose among different system configurations. Respondents preferred choosing none of the presented systems over choosing a system. Potential for the residential and community storage concept with joint usage is found. High levels of autarky have a high utility. Consumers favor ownership over use rights and are willing to give up control to provide services for the grid. Market opportunities for cooperatives, regional power providers, and new market entrants exist. The study can assist in creating customer-focused business models and implementing multi-purpose use cases with value for different actors in the energy system.
•Empirical study shows potential for new battery storage business models.•Market potential for residential and community storage systems is found.•Ownership, autarky and control are key product attributes.•Opportunities for regional partners and provision of grid services are found.•Findings provide a basis to drive innovation in the field of energy storage.
Abstract
The NA64 experiment at the CERN North Area searches for dark matter production via both visible and invisible decays of sub-GeV vector mediators, such as the dark photon
A
′. In a first data ...taking period from 2016-2018,
A′
generation from the reaction e Z → e Z
A
′ and subsequent decays
A
′
→
χ
χ
¯
and
A
′ → e
+
e
−
was studied with the help of an active dump set-up using 100 GeV/
c
and 150 GeV/
c
electrons. Recently, an extension of the performed searches was proposed using a 150 GeV/
c
muon beam, available at the M2 beamline at CERN. These measurements would allow for additional coverage of parameter space towards higher
A
′ masses and would open the possibility for searches for a new gauge boson Z
μ
that would couple predominantly to the second and third lepton generations. We will present both the analysis of the available NA64 data as well as future plans for searches with muon and electron beams that are proposed within the “Physics Beyond Colliders” framework at CERN, including optimisation of the M2 optics and integration studies for implementing NA64
μ
in the EHN2 experimental area.
The colloidal synthesis and assembly of semiconductor nanowires continues to attract a great deal of interest. Herein, we describe the single‐step ligand‐mediated synthesis of single‐crystalline ...CsPbBr3 perovskite nanowires (NWs) directly from the precursor powders. Studies of the reaction process and the morphological evolution revealed that the initially formed CsPbBr3 nanocubes are transformed into NWs through an oriented‐attachment mechanism. The optical properties of the NWs can be tuned across the entire visible range by varying the halide (Cl, Br, and I) composition through subsequent halide ion exchange. Single‐particle studies showed that these NWs exhibit strongly polarized emission with a polarization anisotropy of 0.36. More importantly, the NWs can self‐assemble in a quasi‐oriented fashion at an air/liquid interface. This process should also be easily applicable to perovskite nanocrystals of different morphologies for their integration into nanoscale optoelectronic devices.
Cubes, wires, and assemblies: Single‐crystalline perovskite nanowires were prepared directly from precursor powders in a single‐step ligand‐assisted process by ultrasonication. The nanowires likely resulted from the oriented attachment of nanocubes. Quasi‐oriented self‐assemblies of the perovskite nanowires were fabricated at air/liquid interfaces.
Polysaccharides have attracted considerable attention in a broad range of applications in recent years, which is due to their remarkable features such as biocompatibility, biodegradability, renewable ...origin, and facile modification. Considerable research efforts have been focused on developing polysaccharide nanoparticles and to promote their applications in various areas and biomedicine in particular. The present review highlights the properties of common polysaccharides used in nanoparticle formation as well as strategies to fabricate polysaccharide nanoparticles. Furthermore, the combination of polysaccharide nanoparticles and polymers is presented and brought into the context of applications. Finally, applications of polysaccharide nanoparticles as nano-delivery system, Pickering emulsion stabilisers, and material reinforcing agent in the fields of nanomedicine, cosmetics, and food system are highlighted. Moreover, this review describes and critically discusses present limitations and drawbacks in the preparation and use of polysaccharide nanoparticles, revealing directions to develop polysaccharide nanoparticles for further utilisation in various applications in the future.
The present review highlights the developments in polysaccharide nanoparticles with a particular focus on applications in biomedicine, cosmetics and food.
Objectives
Accurate assessment of knee alignment and leg length discrepancy is currently measured manually from standing long-leg radiographs (LLR), a process that is both time consuming and poorly ...reproducible. The aim was to assess the performance of a commercial available AI software by comparing its outputs with manually performed measurements.
Materials and methods
The AI was trained on over 15,000 radiographs to measure various clinical angles and lengths from LLRs. We performed a retrospective single-center analysis on 295 LLRs obtained between 2015 and 2020 from male and female patients over 18 years. AI and expert measurements were performed independently. Kellgren-Lawrence score and reading time were assessed. All measurements were compared and non-inferiority, mean-absolute-deviation (sMAD), and intra-class-correlation (ICC) were calculated.
Results
A total of 295 LLRs from 284 patients (mean age, 65 years (18; 90); 97 (34.2%) men) were analyzed. The AI model produces outputs on 98.0% of the LLRs. Manually annotations were considered as 100% accurate. For each measurement, its divergence was calculated, resulting in an overall accuracy of 89.2% when comparing the AI outputs to the manually measured. AI vs. mean observer revealed an sMAD between 0.39 and 2.19° for angles and 1.45–5.00 mm for lengths. AI showed good reliability in all lengths and angles (ICC ≥ 0.87). Non-inferiority comparing AI to the mean observer revealed an equivalence-index (
γ
) between 0.54 and 3.03° for angles and − 0.70–1.95 mm for lengths. On average, AI was 130 s faster than clinicians.
Conclusion
Automated measurements of knee alignment and length measurements produced with an AI tool result in reproducible, accurate measures with a time savings compared to manually acquired measurements.
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