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1.	Amombo Noa, Francoise Mystere, 1988, et al. (författare) A unified topology approach to dot-, rod-, and sheet-MOFs 2021 Ingår i: Chem. - : Elsevier BV. - 2451-9294 .- 2451-9308. ; 7:9, s. 2491-2512 Tidskriftsartikel (refereegranskat)abstract Metal-organic frameworks made from multi-metal-ion units in the shape of clusters and rods (termed dot-MOFs and rod-MOFs) are well known. Here, we introduce MOFs with multi-metallic units in the form of sheets-sheet-MOFs. We show exemplars of all three types of units based on structures containing Y3+, Ce3+, or Gd3+ linked by benzene1,2,4,5-tetracarboxylate to give crystals of a dot-MOF in H2NMe2[Y(b-tec)(H2O)] CTH-14, a sheet-MOF in [Ce-3(btec)(Hbtec)(OAc)(HCO2)] CTH-15, and a rod-MOF in 4,4'-azopyridinium[Gd-2(btec)(2)] CTH-16. Cyclic voltammetry shows that CTH-15 stabilizes Ce(IV). Given the fact that sheet-MOFs represent an intellectual advance in the evolution of MOFs, a unified approach is proposed for the topological classification of dot-, rod-, and sheet-MOFs. It is suggested that the stability ofMOFs follow in the trend dot < rod < sheet. For CTH-14-16, the sheet- and the rod-MOF have higher thermal stability. We suggest sheet-MOFs as an additional strategy for making robust MOFs.
2.	Beeren, Sophie R., et al. (författare) The mechanical bond in biological systems 2023 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 9:6, s. 1378-1412 Forskningsöversikt (refereegranskat)abstract The field of mechanically interlocked molecules (MIMs) has advanced rapidly in recent years, with much work focused on their use in materials, sensing, and catalysis. However, the use of MIMs in biology and biomedicine has been limited, despite the identifica-tion of naturally occurring MIMs in DNA and proteins and the poten-tial advantages of the mechanical bond in fields such as nanomedi-cine and tissue engineering. Difficulties in the synthesis of MIMs, along with their limited solubility and stability in biological media, have until recently impeded their wider application in biology. Contemporary advances have, however, enabled a broader integra-tion of the mechanical bond in biology; the mechanical interlocking endows these systems with unique functional advantages. Herein, we summarize recent advances in the application of small-molecule, biologically derived, and polymeric MIMs in biology, highlighting synergies ripe for future exploration.
3.	Benesperi, Iacopo, et al. (författare) Dynamic dimer copper coordination redox shuttles 2022 Ingår i: Chem. - : Elsevier. - 2451-9308 .- 2451-9294. ; 8:2, s. 439-449 Tidskriftsartikel (refereegranskat)abstract Summary Conventional redox mediators based on metal coordination complexes undergo electron transfer through the change in oxidation state of the metal center. However, electron transfer kinetics are offset toward preferred oxidation states when preorganized ligands constrain the reorganization of the coordination sphere. In contrast, we report here on dimeric copper(II/I) redox couples, wherein the extent of oxidation/reduction of two metal centers dictates the dynamic formation of dimer and monomer complexes: the dimeric (Cu(I))2 transitions to monomers of Cu(II). The bis(thiazole/pyrrole)-bipyridine tetradentate ligands stabilize both oxidation states of the unique redox systems. The dynamic dimer redox mediators offer a viable two-electron redox mechanism to develop efficient hybrid solar cells through inhibited recombination and rapid charge transport. Density functional theory calculations reveal inner reorganization energies for single-electron transfer as low as 0.27 eV, marking the dimeric complexes superior redox systems over single complexes as liquid and potentially solid-state electrolytes.
4.	Bermejo-López, Aitor, 1989- (författare) Don't become your own resting state 2022 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 8:12, s. 3154-3155 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Dr. Aitor Bermejo López graduated with a degree in chemistry from the Universidad Autónoma de Madrid. He completed his master’s studies and subsequently obtained a doctoral degree in organic chemistry from Stockholm University with Prof. Belén Martín-Matute. He gained expertise in organometallic catalysis while focusing on the development of new transformations and on the study of their mechanisms. He defended his doctoral thesis recently this year and is eager to see what the future has in store and to grow as a scientist.
5.	Bermejo-López, Aitor, 1989-, et al. (författare) Selective and quantitative functionalization of unprotected α-amino acids using a recyclable homogeneous catalyst 2022 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 8:12, s. 3302-3323 Tidskriftsartikel (refereegranskat)abstract A new Ir(III)-NHC catalyst is reported that shows remarkable activity in the N-alkylation of unprotected amino acids. The catalytic system gives excellent selectivity toward monoalkylated α-amino acids and a high degree of retention of stereochemistry. A wide range of unprotected nonnatural amino acids have been prepared. These compounds represent an array of building blocks that could be used for the direct synthesis of peptidomimetics. The synthesis of amino-acid-based surfactants is also reported. This catalytic method gives the amino acid products in quantitative yield; hence, tedious purifications by derivatization are therefore avoided. Furthermore, although the catalyst is a homogeneous metal complex, it can be recycled and reused for several runs. This also contributes to the efficiency and sustainability of the method.
6.	Breitwieser, Kevin, et al. (författare) Dawn of a new era? A base-metal single-atom catalyst for organic fine chemical synthesis 2024 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 10:6, s. 1633-1635 Tidskriftsartikel (refereegranskat)abstract Single-atom catalysts (SACs) hold the potential to combine the benefits of both heterogeneous and homogeneous catalysis. In this issue of Chem, Beller and co-workers demonstrate the selective insertion of transient copper carbenes into diverse X‒H (X = C, N, O, S) bonds with excellent functional-group tolerance by using a porous Al2O3-supported SAC.
7.	Chen, Xuehan, et al. (författare) Perspective Phosphine oxide additives for perovskite diodes and solar cells 2023 Ingår i: Chem. - : CELL PRESS. - 2451-9308 .- 2451-9294. ; 9:3, s. 562-575 Forskningsöversikt (refereegranskat)abstract Lead halide perovskites have been considered promising semicon-ducting materials for next-generation optoelectronic devices due to their solution processability and excellent optoelectronic proper-ties. Device performance of perovskite light-emitting diodes (PeLEDs) and perovskite solar cells (PSCs) has been rapidly devel-oped during the past decade. Very recently, organic molecules containing phosphine oxide groups have emerged as promising ad-ditives and passivators to improve the device performance and sta-bility of both PeLEDs and PSCs. In this perspective, we summarize recent progress in the development of new phosphine-oxide-based additives for PeLEDs and PSCs. The passivation mechanism, molecule design principle, and structure-property relationship of phosphine oxide molecules for PeLEDs and PSCs are systematically discussed and analyzed. Finally, we provide an outlook on the mo-lecular design of novel phosphine oxide compounds for efficient and stable PeLEDs and PSCs in the future.
8.	Davison, Nathan, et al. (författare) A room-temperature-stable electride and its reactivity : Reductive benzene/pyridine couplings and solvent-free Birch reductions 2023 Ingår i: Chem. - : Elsevier. - 2451-9308 .- 2451-9294. ; 9:3, s. 576-591 Tidskriftsartikel (refereegranskat)abstract In this work, we report the synthesis of a room-temperature-stable electride (RoSE) reagent, namely K+(LiHMDS)e− (1) (HMDS: 1,1,1,3,3,3-hexamethyldisilazide), from accessible starting materials (potassium metal and LiHMDS) via mechanochemical ball milling at 20 mmol scale. Despite its amorphous nature, the presence of anionic electrons in 1, key diagnostic criteria for an electride, was confirmed by both experimental and computational studies. Therefore, by definition, 1 is an electride. Utilizing its anionic electrons, electride reagent 1 exhibited a versatile reactivity profile that includes (1) mediation of C–H activation and C–C coupling of benzene and pyridine and (2) mediation of solvent-free Birch reduction. This work proves the concept of facile mechanochemical synthesis of a room-temperature-stable electride, and it introduces electride 1 to the synthetic chemistry community as a versatile reagent.
9.	Finkelstein-Shapiro, Daniel, et al. (författare) Understanding radiative transitions and relaxation pathways in plexcitons 2021 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 7:4, s. 1092-1107 Tidskriftsartikel (refereegranskat)abstract Molecular aggregates on plasmonic nanoparticles have emerged as attractive systems for the studies of polaritonic light-matter states, called plexcitons. Such systems are tunable, scalable, easy to synthesize, and offer sub-wavelength confinement, all while giving access to the ultrastrong light-matter coupling regime, promising a plethora of applications. However, the complexity of these materials prevented the understanding of their excitation and relaxation phenomena. Here, we follow the relaxation pathways in plexcitons and conclude that while the metal destroys the optical coherence, the molecular aggregate coupled to surface processes significantly contributes to the energy dissipation. We use two-dimensional electronic spectroscopy with theoretical modeling to assign the different relaxation processes to either molecules or metal nanoparticle. We show that the dynamics beyond a few femtoseconds has to be considered in the language of hot electron distributions instead of the accepted lower and upper polariton branches and establish the framework for further understanding.
10.	Hammarström, Leif (författare) Catalyst : Chemistry's Role in Providing Clean and Affordable Energy for All 2016 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 1:4, s. 515-518 Tidskriftsartikel (refereegranskat)abstract Leif Hammarstrom is a professor of chemical physics at Uppsala University, Sweden. He is one of the leaders of the Swedish Consortium for Artificial Photosynthesis, founded in the mid-1990s. He is chair of the Swedish Solar Energy Platform and represents Uppsala University as a core member of the Solar Fuels Institute.
11.	Hutchins, George H., et al. (författare) Covalent bicyclization of protein complexes yields durable quaternary structures 2024 Ingår i: Chem. - : CELL PRESS. - 2451-9308 .- 2451-9294. ; 10:2 Tidskriftsartikel (refereegranskat)abstract Proteins are essential biomolecules and central to biotechnological applications. In many cases, assembly into higher -order structures is a prerequisite for protein function. Under conditions relevant for applications, protein integrity is often challenged, resulting in disassembly, aggregation, and loss of function. The stabilization of quaternary structure has proven challenging, particularly for trimeric and higher -order complexes, given the complexity of involved interand intramolecular interaction networks. Here, we describe the chemical bicyclization of homotrimeric protein complexes, thereby increasing protein resistance toward thermal and chemical stress. This approach involves the structure -based selection of cross -linking sites, their variation to cysteine, and a subsequent reaction with a triselectrophilic agent to form a protein assembly with bicyclic topology. Besides overall increased stability, we observe resistance toward aggregation and greatly prolonged shelf life. This bicyclization strategy gives rise to unprecedented protein chain topologies and can enable new biotechnological and biomedical applications.
12.	Linde, Erika, et al. (författare) Diarylation of N- and O-nucleophiles through a metal-free cascade reaction 2022 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 8:3, s. 850-865 Tidskriftsartikel (refereegranskat)abstract The arylation of heteroatom nucleophiles is a central strategy to reach diarylated compounds that are key building blocks in agrochemicals, materials, and pharmaceuticals. Nucleophilic aromatic substitution is a classical tool for such arylations, and recent developments in hypervalent iodine-mediated arylations allow a wider scope of products. Herein, we combine the benefits of these strategies to enable an efficient and transition-metal-free difunctionalization of N-and O-nucleophiles with two structurally different aryl groups and to provide di-and triarylamines and diaryl ethers in one single step (>100 examples). The core of this strategy is the unique reactivity discovered with specifically designed fluorinated diaryliodonium salts, which unveils novel reaction pathways in hypervalent iodine chemistry. The methodology is suitable for diarylation of aliphatic amines, anilines, ammonia, and even water. It tolerates a wide variety of functional and protecting groups, with the retained iodine substituent easily accessible for derivatization of the products.
13.	Liu, Tianjun, et al. (författare) Molecule additive design for perovskite light-emitting diodes operated at high current densities 2023 Ingår i: Chem. - : CELL PRESS. - 2451-9308 .- 2451-9294. ; 9:8, s. 2058-2059 Forskningsöversikt (refereegranskat)abstract Halide perovskite light emitting diodes (PeLEDs) are enticing candi-dates for displays and lighting. However, most reported PeLEDs are limited for practical applications at high current densities due to decreased efficiency and rapid degradation. Recently, in Nature, Greenham and co-workers developed PeLEDs with exceptional per-formance at a high current density above 1000 mA cm -2, achieved by the introduction of a multifunctional molecule that simulta-neously minimizes non-radiative distributions in emitter layers and suppresses luminescence quenching at the interface between perovskite and charge-transport layers.
14.	Mukherjee, Sourav P., et al. (författare) Graphene Oxide Elicits Membrane Lipid Changes and Neutrophil Extracellular Trap Formation 2018 Ingår i: Chem. - : Elsevier BV. - 2451-9294 .- 2451-9308. ; 4:2, s. 334-358 Tidskriftsartikel (refereegranskat)abstract Understanding the biological interactions of graphene-based materials is important for the safe use of these materials. Previous studies have explored the interaction between graphene oxide (GO) and macrophages but not the impact of GO on neutrophils, key cells of the immune system. Here, we synthesized GO sheets with differing lateral dimensions and showed by using an array of analytical and imaging techniques, including transmission and scanning electron microscopy, confocal microscopy, and time-of-flight secondary ion mass spectroscopy (ToF-SIMS), that GO elicited the formation of neutrophil extracellular traps (NETs). ToF-SIMS revealed pronounced perturbations of plasma membrane lipids, including a decrease in cholesterol and increased levels of oxidized cholesterol species. The induction of NETs was size dependent and associated with the production of mitochondrial reactive oxygen species and calcium influx. Importantly, antioxidant treatment reduced the production of NETs. These studies provide evidence that a previously undescribed biological effect of GO manifests through direct effects on membrane lipids. Graphene oxide (GO) is being investigated for various biomedical applications. Understanding the interactions between GO and living cells is of critical importance for the safe use of these materials in patients. In the present study, we identified effects of GO on neutrophils, the most common type of white blood cell. We first synthesized GO sheets of different sizes and carefully characterized the materials. Then, using various analytical and imaging techniques, we found that GO triggered so-called neutrophil extracellular traps or NETs. NETs are normally deployed by neutrophils to capture and destroy pathogens. We were able to show that GO caused significant changes in the lipid composition of the neutrophil cell membrane, whereby the oxidation of cholesterol set into motion a cascade of intracellular events leading to the formation of NETs. These studies show that GO acts directly on the neutrophil cell membrane and leads to the activation of a conserved anti-pathogen response. Graphene oxide (GO) is a promising material for a variety of biomedical and other applications. The increasing use of GO necessitates careful assessment of potential health hazards. Using primary neutrophils as a model, Mukherjee et al. show that GO elicits neutrophil extracellular traps. Furthermore, by using ToF-SIMS, the authors noted pronounced perturbations of plasma membrane lipids in cells exposed to GO.
15.	Schaufelberger, Fredrik (författare) Vintage ligand powers switchable molecular motors 2023 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 9:8, s. 2053-2055 Tidskriftsartikel (refereegranskat)abstract Creating artificial molecular machines that perform well-defined unidirectional movement in response to stimuli is a challenging task. In this issue of Chem, Crespi, Feringa, and co-workers report a new bis(benzoxazole) ligand-based molecular motor that enables a high degree of external control over motor function through complexation with metal ions.
16.	Schmalzbauer, Matthias, et al. (författare) Redox-Neutral Photocatalytic C-H Carboxylation of Arenes and Styrenes with CO2 2020 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 6:10, s. 2658-2672 Tidskriftsartikel (refereegranskat)abstract Carbon dioxide (CO2) is an attractive one-carbon (C1) building block in terms of sustainability and abundance. However, its low reactivity limits applications in organic synthesis as typically high-energy reagents are required to drive transformations. Here, we present a redox-neutral C-H carboxylation of arenes and styrenes using a photocatalytic approach. Upon blue-light excitation, the anthrolate anion photocatalyst is able to reduce many aromatic compounds to their corresponding radical anions, which react with CO2 to afford carboxylic acids. High-throughput screening and computational analysis suggest that a correct balance between electron affinity and nucleophilicity of substrates is essential. This novel methodology enables the carboxylation of numerous aromatic compounds, including many that are not tolerated in classical carboxylation chemistry. Over 50 examples of C-H functionalizations using CO2 or ketones illustrate a broad applicability. The method opens new opportunities for the valorization of common arenes and may find application in late-stage C-H carboxylation.
17.	Shatskiy, Andrey, et al. (författare) Chemodivergent difunctionalization of alkenes through base-controlled radical relay 2022 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 8:1, s. 12-14 Tidskriftsartikel (refereegranskat)abstract Establishing chemodivergent synthetic strategies remains a daunting task in the realm of free-radical reaction manifolds. In the December issue of Chem, Glorius and co-workers resolve this challenge for selective difunctionalization of aliphatic alkenes. In the disclosed light-promoted radical relay process, switchable trifluoromethylation/alkylation or trifluoromethylation/sulfonylation of alkenes is achieved.
18.	Shatskiy, Andrey, et al. (författare) Controlling Radical Relay Processes with Visible Light 2021 Ingår i: Chem. - : Cell Press. - 2451-9308 .- 2451-9294. ; 7:2, s. 283-285 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Harnessing free radical intermediates for selective functionalization of organic compounds has been widely demonstrated under photocatalytic conditions requiring a distinct photocatalyst. In this issue of Chem, Seo, Chang, and co-workers demonstrate an alternative photocatalyst- free light-mediated approach that allows efficient amidation of aldehydes via N-centered radical intermediate.
19.	Stindt, Charlotte N., et al. (författare) Activating a light-driven molecular motor by metal complexation 2023 Ingår i: Chem. - : CELL PRESS. - 2451-9308 .- 2451-9294. ; 9:8 Tidskriftsartikel (refereegranskat)abstract Designing increasingly complex, responsive, and dynamic molecular systems, whose actions can be controlled by a combination of cooperative stimuli, is a key challenge toward the development of more advanced functional molecular machines. Herein, we report new photochemically driven molecular motors based on a bis(benzoxazole) ligand. Coordination of the ligand to a metal salt leads to the selective in situ activation of a well-defined motor function, which can be deactivated in the presence of a competing ligand. The rotation speed and absorption wavelength are tuned by the choice of metal, allowing unprecedented control of the molecular system. DFT calculations show that the geometry of the metal center influences the rotational barriers and the possibility to couple the rotary motion with the wagging movement at the metal center. The approach presented here will open new avenues toward more complex, dynamic, and coupled systems.
20.	Xu, Bo, et al. (författare) Tailor-Making Low-Cost Spiro[fluorene-9,9′-xanthene]-Based 3D Oligomers for Perovskite Solar Cells 2017 Ingår i: Chem. - : Elsevier. - 2451-9308 .- 2451-9294. ; 2:5, s. 676-687 Tidskriftsartikel (refereegranskat)abstract The power-conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have increased rapidly from about 4% to 22% during the past few years. One of the major challenges for further improvement of the efficiency of PSCs is the lack of sufficiently good hole transport materials (HTMs) to efficiently scavenge the photogenerated holes and aid the transport of the holes to the counter-electrode in the PSCs. In this study, we tailor-made two low-cost spiro[fluorene-9,9′-xanthene] (SFX)-based 3D oligomers, termed X54 and X55, by using a one-pot synthesis approach for PSCs. One of the HTMs, X55, gives a much deeper HOMO level and a higher hole mobility and conductivity than the state-of-the-art HTM, Spiro-OMeTAD. PSC devices based on X55 as the HTM show a very impressive PCE of 20.8% under 100 mW·cm−2 AM1.5G solar illumination, which is much higher than the PCE of the reference devices based on Spiro-OMeTAD (18.8%) and X54 (13.6%) under the same conditions.
21.	Yang, Shun, et al. (författare) Reversibly modulating a conformation-adaptive fluorophore in [2]catenane 2021 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 7:6, s. 1544-1556 Tidskriftsartikel (refereegranskat)abstract Tuning molecular emission by chemicalmeans has long been a fundamental topic, because the emerging methodologies and mechanisms of this topic usually bring a lot of opportunities in many multi-disciplinary applications. Here, we demonstrate the reversible switching of a conformation-adaptive fluorophore, 9,14-diphenyl-9,14-dihydrodibenzo[ a,c]phenazine (DPAC), by incorporating this fluorescent unit into a mechanically interlocked [2]catenane. Taking advantage of the mechanical bond of [2]catenane, the conformational freedom of the DPAC-macrocycle can be modulated by the co-conformational state of the [2]catenane, thus enabling the reversible switching of the fluorescent properties of DPAC. Owing to the mechanically interlocked structure, this fluorescent molecular system can be switched in a dual-mode (wavelength or intensity), visually recognizable, and highly reversible manner. This work provides a distinctmechanism of switchingmolecular emission by modulating conformation-adaptive fluorescent systems in mechanically interlocked structures.
22.	Yang, Yizhou, 1992, et al. (författare) Detachable all-carbon-linked 3D covalent organic framework films for semiconductor/COF heterojunctions by continuous flow synthesis 2022 Ingår i: Chem. - : Elsevier BV. - 2451-9308 .- 2451-9294. ; 8:8, s. 2217-2227 Tidskriftsartikel (refereegranskat)abstract New synthetic strategies are ceaselessly being explored to fabricate covalent organic frameworks (COFs) as continuous materials with controlled morphology. However, making substrate detachable thin layers of 3D COFs, which would allow for film-based applications, has turned out to be particularly difficult. Here, we developed a substrate-catalyzed synthesis in a continuous flow method that successfully realized the fabrication of crystalline detachable all-carbon-linked 3D SBFdiyne-COF films. The key element in the method is a highly controlled interfacial reaction between the Cu substrate and a base flowing over the substrate. Benefiting from the detachability and high quality of the fabricated film, an organic semiconductor/COF heterojunction was constructed, showing high current rectification performance of 104 under forward/reverse bias.
23.	Yuan, Fanglong, et al. (författare) Monolayer 2D polymeric fullerene: A new member of the carbon material family 2022 Ingår i: Chem. - : CELL PRESS. - 2451-9308 .- 2451-9294. ; 8:8, s. 2079-2081 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Two-dimensional (2D) carbon materials have attracted tremendous attention because of their unique properties, but their structures are currently limited to periodic networks of single carbon atoms. Recently in Nature, Zheng and co-workers demonstrate a new monolayer 2D carbon material composed of interconnected fullerene molecules.
24.	Yuan, Jun, et al. (författare) Reducing Voltage Losses in the A-DAD-A Acceptor-Based Organic Solar Cells 2020 Ingår i: Chem. - : CELL PRESS. - 2451-9308 .- 2451-9294. ; 6:9, s. 2147-2161 Tidskriftsartikel (refereegranskat)abstract Power conversion efficiencies (PCEs) of solution-processed organic solar cells (OSCs) have recently reached 17.4% (certified) for single-junction devices. Crucial to this advancement is the development of non-fullerene acceptors (NFAs) since 2015. The recent A-DAD-A NFAs have attracted widespread attention because of their ladder-type electron-deficient-core-based central fused ring with improved transport properties and optimum energy levels. With the synergistic effect of electron-deficient-core and specific molecular geometry, the A-DADA molecules could achieve low voltage losses and high current generation at the same time, reaching new regimes of device physics and photophysics. This perspective will discuss the voltage losses in state-of-the-art A-DAD-A NFA-based OSCs and propose new molecular design strategies to achieve PCEs over 20% in OSCs based on these new acceptors by further decreasing their total voltage losses.
25.	Zhang, Qi, et al. (författare) Muscle-like Artificial Molecular Actuators for Nanoparticles 2018 Ingår i: Chem. - : Cell Press. - 2451-9308 .- 2451-9294. ; 4:11, s. 2670-2684 Tidskriftsartikel (refereegranskat)abstract Muscle tissue performs crucial contraction/extension motions that generate mechanical force and work by consuming chemical energy. Inspired by this naturally created biomolecular machine, artificial molecular muscles are designed and synthesized to undertake linear actuation functions. However, most of these muscle-like actuators are performed at large ensembles, while to realize the nanoscale actuation at the single-to few-molecule level remains challenging. Herein, we developed an artificial muscle-like molecular actuator that can reversibly control the proximity of the attached nano-objects, gold nanoparticles, within the single-molecule length level by its stimuli-responsive muscle-like linear contraction/extension motion. The molecular actuation motion is accompanied by an optical signal output resulting from the plasmonic resonance properties of gold nanoparticles. Meanwhile, the thermal noise of the muscle-like molecular actuator can be overcome by integrating the optical signal over a sufficiently long period.
26.	Chien, Yu-Chuan, 1990-, et al. (författare) Correlations between precipitation reactions and electrochemical performance of lithium-sulfur batteries probed by operando scattering techniques 2022 Ingår i: Chem. - : Elsevier. - 2451-9294. ; 8:5 Tidskriftsartikel (refereegranskat)abstract A comprehensive description of electrochemical processes in the positive electrode of lithium-sulfur batteries is crucial for the utilization of active material. However, the discharge mechanisms are complicated due to various reactions in multiple phases and the tortuosity of the highly porous carbon matrix. In this work, simultaneous measurements of small-angle and wide-angle scattering and cell resistance are performed on operating lithium-sulfur cells. Results indicate that precipitates grow mostly in number, not in size, and that the structure of the carbon matrix is not affected. The comparison of the small-angle and wide-angle scattering reveals the amorphous discharge products found at a low discharge rate. Further analysis demonstrates the correlation between the diffusion resistance and the compositional change of electrolyte in the mesopores at the end of discharge, which suggests that Li-ion deficiency is the limiting factor for sulfur utilization at a medium discharge rate.
27.	Oh, Juwon, et al. (författare) Unraveling Excited-Singlet-State Aromaticity via Vibrational Analysis 2017 Ingår i: Chem. - : Elsevier BV. - 2451-9294. ; 3:5, s. 870-880 Tidskriftsartikel (refereegranskat)abstract SummaryThe concept of excited-state aromaticity is receiving much attention in that completely reversed aromaticity in the excited state (so-called aromaticity reversal) provides crucial insight into photostability, photoreactivity, and its application to the photosynthetic mechanism and photoactive materials. Despite this significance, experimental elucidation of excited-state aromaticity is still unsolved, particularly for the excited singlet state. Here, as an unconventional approach, time-resolved IR (TRIR) spectroscopy on aromatic and anti-aromatic hexaphyrin congeners shed light on excited-singlet-state aromaticity. The contrasting spectral features between the Fourier transform IR and TRIR spectra reveal the aromaticity-driven structural changes, corroborating aromaticity reversal in the excited singlet states. Our paradigm for excited-state aromaticity, the correlation of IR spectral features with aromaticity reversal, provides another fundamental key to understanding the role of (anti)aromaticity in the stability, dynamics, and reactivity in the excited singlet state of π-conjugated molecular systems.
28.	Zeisel, L, et al. (författare) Selective cellular probes for mammalian thioredoxin reductase TrxR1: rational design of RX1, a modular 1,2-thiaselenane redox probe 2022 Ingår i: Chem. - : Elsevier BV. - 2451-9294. ; 8:5, s. 1493-1517 Tidskriftsartikel (refereegranskat)

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