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Mutual neutralization of hydronium (H3O+) and hydroxide (OH−) ions is a very fundamental chemical reaction. Yet, there is only limited experimental evidence about the underlying reaction mechanisms. Here, we report three-dimensional imaging of coincident neutral products of mutual-neutralization reactions at low collision energies of cold and isolated ions in the cryogenic double electrostatic ion-beam storage ring (DESIREE). We identified predominant H2O + OH + H and 2OH + H2 product channels and attributed them to an electron-transfer mechanism, whereas a minor contribution of H2O + H2O with high internal excitation was attributed to proton transfer. The reported mechanism-resolved internal product excitation, as well as collision-energy and initial ion-temperature dependence, provide a benchmark for modeling charge-transfer mechanisms.

We report here an experimental-computational study of hydrated TiO2 anatase nanoparticles interacting with glycine, where we obtain quantitative agreement of the measured adsorption free energies. Ab initio simulations are performed within the tight binding and density functional theory in combination with enhanced free-energy sampling techniques, which exploit the thermodynamic integration of the unbiased mean forces collected on-the-fly along the molecular dynamics trajectories. The experiments adopt a new and efficient setup for electrochemical impedance spectroscopy measurements based on portable screen-printed gold electrodes, which allows fast and in situ signal assessment. The measured adsorption free energy is −30 kJ/mol (both from experiment and calculation), with preferential interaction of the charged group which strongly adsorbs on the TiO2 bridging oxygens. This highlights the importance of the terminal amino groups in the adsorption mechanism of amino acids on hydrated metal oxides. The excellent agreement between computation and experiment for this amino acid opens the doors to the exploration of the interaction free energies for other moderately complex bionano systems.

Polyelectrolyte porous membranes (PPMs) have numerous applications in modern science and technology. Here, we describe a new platform for creating multifunctional supramolecular PPMs (SPPMs) by cross-linking of single-component homopoly(ionic liquid)s (PILs) containing hydrophilic anions (Br–, MBry–, M = Sn, Pb, Sb, Bi) with H2O molecules. With a range of experimental evidence and support from theoretical calculations, we show that the porous architecture is formed by H2O molecules-induced phase separation of the polycationic moieties of the homo-PILs between their polar and apolar domains, which are cross-linked together by multiple hydrogen (H)-bonding interactions. Furthermore, we discover these SPPMs show reversible, dynamic, wide-range color tuning, depending on the excitation wavelength, as well as ultrasensitive color change toward humidity and temperature stimuli, endowing them with great promise in color-on-demand applications. These findings, together with the scalable and green synthetic approach, bode well for advanced membrane materials and color-on-demand applications based upon such SPPM systems.

Perovskite solar cells (PSCs) based on formamidinium (FA+) lead tri-halide (FAPbI3) have achieved remarkable power conversion efficiencies exceeding 26%. However, both achieving commercially available device stability and reaching the Shockley–Queisser limit remain significant challenges. Additionally, the degradation mechanisms of FAPbI3-based PSCs are inadequately understood in relation to the association between fragmented FA+ and variations in the properties of crystals and energy bands. In this study, a comprehensive analysis based on grazing incidence wide-angle X-ray diffraction revealed a substantial mismatch between the microstrain and dislocation density, attributable to the formation of local intragrain planar defects during the thermal degradation of metal halide perovskite (MHP) films. Further analysis based on X-ray photoemission spectroscopy indicated an initial redistribution of anions, followed by the detrimental decomposition of the A-cation, resulting in potential by-products owing to the thermal dissociation of FA+ within the MHP film. Exceeding the performance limit for FA+ dissociation, the degradation of the MHP film induced a significant change in the valence band owing to the prevalence of fragmented FA+ and vapourization of halide within the MHP film. The widening of the charge inversion layer in the MHP film can be caused by an increase in by-product substitutions. Our study provides valuable insights for enhancing the commercial viability of improving the overall performance of PSCs.

Photodissociation of ironpentacarbonyl [Fe-1(CO)(5)] in solution generates transient species in different electronic states, which we studied theoretically. From ab initio molecular dynamics simulations in ethanol solution, the closed-shell parent compound Fe-1(CO)(5) is found to interact weakly with the solvent, whereas the irontetracarbonyl [Fe(CO)(4)] species, formed after photodissociation, has a strongly spin-dependent behavior. It coordinates a solvent molecule tightly in the singlet state [Fe-1(CO)(4)] and weakly in the triplet state [Fe-3(CO)(4)]. From the simulations, we have gained insights into intersystem crossing in solvated irontetracarbonyl based on the distinct structural differences induced by the change in multiplicity. Alternative forms of coordination between Fe-1(CO)(4) and functional groups of the ethanol molecule are simulated, and a quantum chemical investigation of the energy landscape for the coordinated irontetracarbonyl gives information about the interconversion of different transient species in solution. Furthermore, insights from the simulations, in which we find evidence of a solvent exchange mechanism, challenge the previously proposed mechanism of chain walking for under-coordinated metal carbonyls in solution.

As a versatile nanomaterial derived from renewable sources, nanocellulose has attracted considerable attention for its potential applications in various sectors, especially those focused on water treatment and remediation. Here, we have combined atomic force microscopy (AFM) and reactive molecular dynamics (RMD) simulations to characterize the interactions between cellulose nanofibers modified with carboxylate or phosphate groups and the protein foulant model bovine serum albumin (BSA) at pH 3.92, which is close to the isoelectric point of BSA. Colloidal probes were prepared by modification of the AFM probes with the nanofibers, and the nanofiber coating on the AFM tip was for the first time confirmed through fluorescence labeling and confocal optical sectioning. We have found that the wet-state normalized adhesion force is approximately 17.87 +/- 8.58 pN/nm for the carboxylated cellulose nanofibers (TOCNF) and about 11.70 +/- 2.97 pN/nm for the phosphorylated ones (PCNF) at the studied pH. Moreover, the adsorbed protein partially unfolded at the cellulose interface due to the secondary structure's loss of intramolecular hydrogen bonds. We demonstrate that nanocellulose colloidal probes can be used as a sensitive tool to reveal interactions with BSA at nano and molecular scales and under in situ conditions. RMD simulations helped to gain a molecular- and atomistic-level understanding of the differences between these findings. In the case of PCNF, partially solvated metal ions, preferentially bound to the phosphates, reduced the direct protein-cellulose connections. This understanding can lead to significant advancements in the development of cellulose-based antifouling surfaces and provide crucial insights for expanding the pH range of use and suggesting appropriate recalibrations.

Adsorption free energies of 32 small biomolecules (amino acids side chains, fragments of lipids, and sugar molecules) on 33 different nanomaterials, computed by the molecular dynamics - metadynamics methodology, have been analyzed using statistical machine learning approaches. Multiple unsupervised learning algorithms (principal component analysis, agglomerative clustering, and K-means) as well as supervised linear and nonlinear regression algorithms (linear regression, AdaBoost ensemble learning, artificial neural network) have been applied. As a result, a small set of biomolecules has been identified, knowledge of adsorption free energies of which to a specific nanomaterial can be used to predict, within the developed machine learning model, adsorption free energies of other biomolecules. Furthermore, the methodology of grouping of nanomaterials according to their interactions with biomolecules has been presented.

Studying larger nucleophiles in bimolecular nucleophilic substitution (SN2) reactions bridges the gap from simple model systems to those relevant to organic chemistry. Therefore, we investigated the reaction dynamics between the methoxy anion (CH3O−) and iodomethane (CH3I) in our crossed-beam setup combined with velocity map imaging at the four collision energies 0.4, 0.7, 1.2, and 1.6 eV. We find the two ionic products I− and CH2I−, which can be attributed to the SN2 and proton transfer channels, respectively. The proton transfer channel progresses in a previously observed fashion from indirect to direct scattering with increasing collision energy. Interestingly, the SN2 channel exhibits direct dynamics already at low collision energies. Both the direct stripping, leading to forward scattering, and the direct rebound mechanism, leading to backward scattering into high angles, are observed.

Alkali and quaternary ammonium cations interact with negatively charged cellulose nanocrystals (CNCs) bearing sulfated or carboxylated functional groups. As these are some of the most commonly occurring cations CNC encounter in applications, the thermodynamic parameters of these CNC-counterion interactions were evaluated with isothermal titration calorimetry (ITC). Whereas the adsorption of monovalent counterions onto CNCs was thermodynamically favourable at all evaluated conditions as indicated by a negative Gibbs free energy, the enthalpic and entropic contributions to the CNC-ion interactions were found to be strongly dependent on the hydration characteristics of the counterion and could be correlated with the potential barrier to water exchange of the respective ions. The adsorption of chaotropic cations onto the surface was exothermic, while the interactions with kosmotropic cations were endothermic and completely entropy-driven. The interactions of CNCs with more bulky quaternary ammonium counterions were more complex, and the mechanism of interaction shifted from electrostatic interactions with surface charged groups of CNCs towards adsorption of alkyl chains onto the CNC hydrophobic planes when the alkyl chain length increased.

Polyelectrolyte complexes (PECs) are polymeric structures formed by the self-assembly of oppositely charged polymers. Novel biomaterials based on PECs are currently under investigation as drug delivery systems, among other applications. This strategy leverages the ability of PECs to entrap drugs under mild conditions and control their release. In this study, we combined a novel and sustainably produced hemicellulose-rich lignosulphonate polymer (EH, negatively charged) with polyethyleneimine (PEI) or chitosan (CH, positively charged) and agar for the development of drug-releasing PECs. A preliminary screening demonstrated the effect of several parameters (polyelectrolyte ratio, temperature, and type of polycation) on PECs formation. From this, selected formulations were further characterized in terms of thermal properties, surface morphology at the microscale, stability, and ability to load and release methylene blue (MB) as a model drug. EH/PEI complexes had a more pronounced gel-like behaviour compared to the EH/CH complexes. Differential scanning calorimetry (DSC) results supported the establishment of polymeric interactions during complexation. Overall, PECs' stability was positively affected by low pH, ratios close to 1:1, and the addition of agar. PECs with higher EH content showed a higher MB loading, likely promoted by stronger electrostatic interactions. The EH/CH formulation enriched with agar showed the best sustained release profile of MB during the first 30 h in a pH-dependent environment simulating the gastrointestinal tract. Overall, we defined the conditions to formulate novel PECs based on a sustainable hemicellulose-rich lignosulphonate for potential applications in drug delivery, which promotes the valuable synergy between sustainability and the biomedical field.

The thermodynamic properties of four binary mixtures of deep eutectic solvent (DES), i.e., ChCl/Gly (choline chloride + glycerol at a molar ratio of 1:2) and ChCl/EG (choline chloride + ethylene glycol at a molar ratio of 1:2) with two common co-solvents, i.e., dimethyl sulfoxide (DMSO) and isopropanol (IPA), were studied. Density and viscosity were determined at temperatures from 288.15 to 323.15 K, while measuring the enthalpy of mixing was performed at 308.15 and 318.15 K. The volumetric properties (i.e., excess molar volume and excess partial molar volume) and excess viscosities (i.e., viscosity deviation and logarithmic excess viscosity) were further calculated to investigate the effects of temperature, types of co-solvent and DES, and their contents on the non-ideal behavior of these systems, where the influence of treating the DES as a mixture of two components or a pseudo-component was discussed. The results of volumetric properties indicate that the combined influence of packing effects and H-bonding interactions between the DES and co-solvents led to the contraction of mixture volume, and the results of excess viscosities show H-bonding interactions play an important role in their variations. The results of enthalpy of mixing show that the mixing of DES with IPA is endothermic, while the mixing of DES with DMSO is exothermic. Furthermore, the nonrandom two-liquid (NRTL) model and Gibbs-Helmholtz equation were combined to represent the experimental results of the enthalpy of mixing, and the total average relative deviation (ARD) of all studied systems is 5.43%., Validerad;2024;Nivå 2;2024-03-28 (hanlid);Funder: State Key Laboratory of Material-Oriented Chemical Engineering in China; National Natural Science Foundation of China (22011530112);Full text license: CC BY 4.0

The Empirical Valence Bond (EVB) method has long been recognised as a reliable approach for the calculation of free energies of reactions in heterogeneous electrochemical environments. In spite of its established efficacy, existing implementations and protocols often pose challenges due to their tediousness or lack of transparency. This work introduces an open-source Python implementation of the EVB method, specifically designed to enhance accessibility and comprehension of the method making it highly suited for educational purposes. Recommendations are provided for integrating the methodology into the GROMACS application programming interface, to facilitate its integration into computational chemistry workflows and accellerating research. The program is demonstrated through various computations, including a short EVB study on the dissociation of \COt and tetraphenylporphyrin in the vicinity of a graphene sheet in water and dimethylformamide. Moreover, a novel analytical expression for computing the free energy profile is presented, showing promising agreement with the canonical discretised method.

I jakt på nya energikällor undersöks idag potentialen hos hydrovoltaiska generatorer. Detta är en typ av generator som utvinner elektricitet genom direkt interaktion mellan vatten och ett material. En variant av denna anordning är den avdunstningsdrivna hydrovoltaiska generatorn. Denna består av ett poröst material som är delvis nedsänkt i vatten, som då dras upp i materialet genom kapillärkrafter och avdunstar från dess yta. Detta skapar ett flöde av vatten genom materialet, vilket genererar en elektrisk spänning tack vare ett elektrokinetiskt fenomen som kallas för strömningspotential. Denna studie undersöker huruvida hydro- och aerogeler gjorda av nanofibriller från vassleprotein utgör lämpliga porösa material för den ovan beskrivna generatorn. Då det är en biprodukt från mejeriindustrin är vassleprotein billigt och förnybart. Gelerna har dessutom egenskaper som väntas främja en hög strömningspotential, såsom hydrofilicitet, små porer, och en ytladdning. I studien testades två sorters hydrogeler, varav den ena korslänkades med hjälp av citronsyra för att göra den mer vattentålig. Aerogeler tillverkades med tre olika koncentrationer av vassleprotein. Dessa geler frystes också på tre olika sätt inför att de frystorkades för att bilda aerogeler. De frystes vid -80 °C i en frys, vid -196 °C i flytande kväve, samt genomgick riktad frysning i flytande kväve. Detta för att variera deras porstruktur. När de olika gelerna testades som hydrovoltaiska generatorer gav de olika spänningar, men ingen mätbar ström. När spänningen från de olika generatorerna mättes över tid följde den oftast samma mönster av en inledande skarp ökning följd av en långsammare minskning som slutligen planade ut mot något jämviktsvärde. Den genomsnittliga maxspänningen från de olika gelerna varierade mellan 73 och 149 mV, huvudsakligen beroende på vilken frysmetod som använts. Längre tester visade att aerogelerna kunde upprätthålla en spänning på runt 60 mV i minst 19 timmar. Hydrogelernas spännings, In search of new power sources, scientists are investigating hydrovoltaic devices. This is a type of device that generates electricity from the direct interaction between water and a material. One such device is the evaporation-driven hydrovoltaic device. It consists of a porous material that is partially submerged into water, which rises though the material through capillary forces and evaporates from its surface. This creates a flow of water through the material which gives rise to an electric voltage, through an electrokinetic phenomenon called the streaming potential. This study investigates whetherhydro- and aerogels made from whey protein nanofibrils are a suitable porous material for these devices. As a by-product from the dairy industry, whey protein is cheap and renewable. The gels also have properties which are beneficial for generating a high streaming potential, such as hydrophilicity, small pores, and charged surface groups. In the study, two types of hydrogels were tested, one of which was treated with citric acid as a crosslinker in order to increase their stability in water. Aerogels were fabricated with three different initial concentrations of WPI. The gels were also frozen in three different ways before being freeze-dried to create aerogels. They were frozen at -80 °C in a freezer, at -196 °C by submersion in liquid nitrogen, and through directional freezing using liquid nitrogen, in order to vary their pore structure. When tested as hydrovoltaic devices, the gels did produce voltages, but no measurable currents. When measured over time, the voltages of most aerogels followed the same pattern with a fast initial increase followed by a slow decrease which levelled out towards some equilibrium voltage. The average maximum voltages for the aerogels varied between 73 and 149 mV, depending mostly on the freezing method. Varying the WPI concentration showed no significant effect on the voltage. Long term tests showed that the gels could sustain a voltag

Idag har inte alla människor tillgång till rent vatten trots att det är en mänsklig rättighet. För att lösa detta problem har olika reningsmetoder som destillation och membranfiltrering föreslagits, men på senare tid har också framställning av filter från animaliska proteiner som vassle undersökts som alternativ för vattenrening. I ett försök att öka den ekologiska hållbarheten, ämnar detta projekt att undersöka växtbaserade proteiner som alternativ till vassleproteinisolat (WPI) för produktion av proteinnanofibrill (PNF) - baserade vattenfilter. Potatisproteinisolat (PPI) har valts som växtproteinkälla och löslighet samt bildning av PNF-baserade vattenfilter har undersökts. Slutligen har PPI-filter jämförts med WPI-filter med avseende på adsorption av ibuprofen från vatten. PPI-filter har producerats och jämförts med WPI, men det går inte att dra några tydliga slutsatser om skillnaden i effektivitet av adsorption av ibuprofen.

Nonyfenoletoxylater tillhör en grupp av ickejoniska tensider, vars nedbrytningsprodukt nonylfenol kan bioackumuleras i miljön och har långtgående negativa effekter på vattenlevande organismer. Nonylfenoler har även reproduktiv påverkan och klassas som hormonstörande. Projektet syftar därför till att ersätta nonylfenoletyoxylater mot ett säkrare och miljövänligare alterantiv inom kursen KD2350 Ytor, kolloider och mjuka material. Ytterligare bedöms olika lösningsmedels lämplighet. Analysmetoder inkluderade dropptest, DLS, och visuell granskning av emulsionssystemen. Laborationer med ickejonisk tensid utfördes med varierande koncentrationer av lösningmedel, samtensider, etoxyleringsgrad, tensidhalt och salthalt för att skapa önskade emulsionssystem. Resultaten visar att det är möjligt att ersätta etoxylerade nonylfenoler med en mindre skadlig tensid. Tensiderna beter sig dock olika och det är inte möjligt att ersätta en nonylfenol med en etoxylerad alkohol med samma etoxyleringsgrad rakt av. De slutliga erhållna emulsionssystemen var transparenta, men var mycket känsliga för temperatur. Resultaten som erhölls från projektets laborationer visar dock avvikelser från den teori som finns. Ett exempel är att flera källor skriver att ickejoniska tensider till skillnad från joniska tensider inte kräver en samtensid. Utifrån försöken bildades det inte en mikroemulsion när ingen samtensid i form av alkohol tillsattes till de ickejoniska emulsionerna. Försöket utfördes däremot endast på två tensider med etoxyleringsgrad 8 och 10. Det är möjligt att tensiderna med högre etoxyleringsgrader kan bilda mikroemulsioner utan tillsats av en samtensid.

This thesis explores the evaporation kinetics of various polymer-solvent and binary solvent mixtures to explore possible connections between the solutions properties and their evaporation process. By looking at the evaporation of polymer-solutions and binary-solvent solutions, through the change in weight as the solvent evaporates and the evaporation rate of the evaporation process, potential connections could be found. The results indicate that the presence of polymers influence the solvent evaporation, with polystyrene (PS) generally accelerating and polymethyl methacrylate (PMMA) either decelerating or having minimal impact on evaporation rates. Binary solvent mixtures exhibited non-proportional increases in evaporation rates, suggesting complex intermolecular interactions, but no apparent patterns between their properties and deviation in the evaporation process. This would need further research to find possible connections to be able to predict the evaporation process. But these findings highlight the importance of understanding polymer-solvent compatibility and evaporation dynamics to enhance performance and to identify environmentally friendly solvents for organic photovoltaic (OPV) cell fabrication., Detta examensarbete undersöker avdunstningskinetiken hos olika polymer-lösningsmedel och binära lösningsmedelsblandningar för att utforska möjliga samband mellan lösningarnas egenskaper och deras avdunstningsprocess. Genom att studera avdunstningen av polymer-lösningar och binära lösningsmedelslösningar, genom förändringen i vikt när lösningsmedlet avdunstar och avdunstningshastigheten, kan potentiella samband identifieras. Resultaten indikerar att närvaron av polymerer påverkar lösningsmedlets avdunstning, där polystyren (PS) generellt accelererar och polymetylmetakrylat (PMMA) antingen decelererar eller har minimal inverkan på avdunstningshastigheterna. Binära lösningsmedelsblandningar visade icke-proportionella ökningar i avdunstningstider, vilket tyder på komplexa intermolekylära interaktioner, men inga tydliga mönster mellan deras egenskaper och avvikelser i avdunstningsprocessen kunde identifieras. Ytterligare forskning behövs för att finna möjliga samband för att kunna förutsäga avdunstningsprocessen. Dessa fynd understryker vikten av att förstå polymer-lösningsmedelskompatibilitet och avdunstningsdynamik för att förbättra effektiviteten och kunna identifiera miljövänliga lösningsmedel för tillverkning av organiska solceller (OPV).

Efficient energy harvesting through full solar spectrum utilization has been considered a promising solution to world energy and environmental issues. In this direction, lead sulphide (PbS) quantum dot (QD) based hybrid materials find greater application due to their near-infrared (NIR) active photo response. Slower charge injection and inefficient charge separation limit photoactive response of such NIR active low band gap semiconductor like PbS QDs. Moreover, constructing dual charge transfer pathways in a PbS QDs based nanocomposite through the formation of hybrids with suitable materials can be advantageous in suppressing the charge recombination. In this work, we have synthesized a nanocomposite after decorating the PbS-QDs with semiconducting TiO2 nanoparticles modified with multiwall carbon nanotubes (MWCNT) and thus forming the tri-hybrid (PbS-TiO2-MWCNT) nanocomposites. The enhanced photo-activities of the tri-hybrid, as compared to di-hybrids like PbS-TiO2, PbS-MWCNT were confirmed by the steady state, time-resolved photoluminescence (TRPL) measurements and reactive oxygen species (ROS) generation measurements. Higher ROS generation in the tri-hybrid has been correlated with a faster interfacial electron transfer due to the dual charge injection pathway of PbS QD to TiO2 and MWCNT. The enhanced activity of the trio-hybrid has also been analyzed from the first principal calculations in light of an efficient interfacial electron transfer as a result of the dual charge injection pathway. The photoelectrochemical water-spilling response of the photoanodes in terms of photocurrent density, electrochemical impedance, and Mott-Schottky measurements on PbS-TiO2 and PbS-TiO2-MWCNT photoanodes reveal that a combination of MWCNT and TiO2 exhibits an increase in electrical double layer capacitance, decrease in series resistance and enhancement of carrier density with NIR illumination at the heterojunction. Overall, all the dynamical studies at the interface of the tri

Coupling the electrooxidation of organic compounds (EOO) with hydrogen evolution can be a sustainable way for green hydrogen production, and therefore it 's of great interest to the development of suitable electrocatalysts for efficient EOO. In this study, we present the successful solvothermal synthesis of a Pt-based electrocatalyst for an ethanol oxidation reaction (EOR), using a coral-like structure as substrate which was prepared by plasma electrolytic oxidation (PEO) on a metallic niobium. Chemical analysis revealed the predominance of SnO2 in the PEO structure, while Pt doping demonstrated selectivity on the surface of the electrocatalyst. Cyclic voltammograms indicate a high electrochemically active surface area (122.45 m2 gPt-1 ), with an onset potential of 0.27 V vs. SHE. In-situ spectroelectrochemical analysis confirm the efficient ethanol electrooxidation with remarkable selectivity in C-C bond cleavage. The prepared electrocatalyst stands out as a promising contribution to advances in green hydrogen production by coupling EOR with hydrogen evolution.

To achieve efficient conversion of nitrate to ammonia, it is necessary to design and develop electrode materials with high activity and efficiency for the electrocatalytic reduction reaction of nitrate (NO3RR). Due to its unique semi-metallic properties, the vacancy orbitals of boron are prone to accommodate electrons, so doping element B with transition metals is expected to change the local electronic configuration of the metal, which in turn affects the corresponding catalytic reaction. Here, we propose a new strategy for the preparation of metal borides by using dodecahydro-closo-dodecaborate and Co2+ complexed and calcined to prepare a novel metal boride-Co2B for electrocatalytic nitrate reduction. This modification considerably enhances the performance of NO3RR. Co2B exhibited a Faradaic efficiency of NH4+ (FENH4+) as high as 96.61 % at -0.5 V vs. RHE, achieving a remarkable NH4+ yield of 5.73 mg h-1 mgcat - 1. This study provides a new approach for designing catalysts for environmentallyfriendly ammonia synthesis.

The pursuit of sensitive fluorescent chromophores with integrated aggregation-induced emission (AIE) and twisted intramolecular charge transfer (TICT) properties are attractive due to the tunable emission properties and increased intensity. However, this type of chromophore has yet to be exemplified mechanistically. In this study, a strategy is presented for manipulating the formation of TICT and the AIE effect through molecular engineering. The feasibility of TICT properties is validated by theoretical calculations and ultrafast spectroscopies. By precisely adjusting the hydrophobicity of the donor group, the fluorescence is significantly enhanced through the addition of poor solvent. These findings not only provide mechanistic elucidation for chromophores exhibiting integrated TICT and AIE properties in various environmental conditions but also underscore the critical factors for the systematic design of chromophores with high tunability and strong emissions.

The effective treatment of nitrate (NO3- ) in water as a nitrogen source and electrocatalytic NO3- reduction to ammonia (NH3 ) (NRA) have become preferred methods for NO3--to-NH3 conversion. Achieving efficient NO3--to-NH3 conversion requires the design and development of electrode materials with high activity and efficiency for the electrocatalytic NRA reaction. Herein, based on the special properties of dodecahydro- closo -dodecaborate anions, a BCN matrix, loaded with platinum -group nanoparticles (namely, Pd/BCN, Pt/BCN, and Ru/BCN), was prepared using a simple method for the electrocatalytic NRA reaction. Results showed that Pd/BCN exerts the best catalytic effect on the NRA reaction. The NH3 production rate reached 12.71 mg h- mgcat.-1 at -1.0 V vs. RHE. Faraday efficiency reached 91.79 %, which can be attributed to the more uniform distribution of the nanoparticles. Furthermore, Pd/BCN exhibited high cycling stability and resistance to ionic interference. Moreover, the density functional theory calculations indicated that small and well -distributed Pd nanoclusters in the BCN matrix have a large active surface area and promote the catalytic process. This study provides a new strategy to design catalysts for green ammonia synthesis.

The photogenerated charge carrier separation and transportation of inside photocathodes can greatly influence the performance of photoelectrochemical (PEC) H2 production devices. Coupling TiO2 with p-type semiconductors to construct heterojunction structures is one of the most widely used strategies to facilitate charge separation and transportation. However, the band position of TiO2 could not perfectly match with all p-type semiconductors. Here, taking antimony selenide (Sb2Se3) as an example, a rational strategy was developed by introducing a viologen electron transfer mediator (ETM) containing polymeric film (poly-1,1′-dially-[4,4′-bipyridine]-1,1′-diium, denoted as PV2+) at the interface between Sb2Se3 and TiO2 to regulate the energy band alignment, which could inhibit the recombination of photogenerated charge carriers of interfaces. With Pt as a catalyst, the constructed Sb2Se3/PV2+/TiO2/Pt photocathode showed a superior PEC hydrogen generation activity with a photocurrent density of −18.6 mA cm−2 vs. a reversible hydrogen electrode (RHE) and a half-cell solar-to-hydrogen efficiency (HC-STH) of 1.54% at 0.17 V vs. RHE, which was much better than that of the related Sb2Se3/TiO2/Pt photocathode without PV2+ (−9.8 mA cm−2, 0.51% at 0.10 V vs. RHE)., QC 20230111

The present work focuses on the structural properties, spectroscopic signatures, intermolecular hydrogen bonding interactions, chemical and biological activity of nicotinamide (NIC) based on its monomeric and trimeric models using density functional theory and vibrational spectroscopy. FT-IR and FT-Raman spectra were obtained using the double-side forward-backward acquisition mode under vacuum. UV-Vis absorption spectra were recorded in methanol and compared with the calculated values. Geometry optimization and vibrational wavenumbers were obtained with the aid of Gaussian 09 program packages. The structural analysis of NIC revealed that the trimeric model was in better agreement with the experimental values than the monomer due to the incorporation of nearest hydrogen bond interactions. Spectroscopic results showed that NH2 and C = O groups of NIC were involved in intermolecular interactions in the trimeric model. The natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) analyses determined the presence, strength as well as nature of the hydrogen bonds were partially covalent. The lesser value of the HOMO-LUMO energy gap for the trimeric model indicated higher reactivity than monomer. Moreover, chemical reactivity was calculated using molecular electrostatic potential surface (MESP) and reactivity descriptors. The docking studies for NIC with several targets explored its biological activity.

The Haber-Bosch process produces NH3 from N2 and H21,2, typically with Fe and Ru3. HB has been proposed as the most important scientific invention in the 20th century4. The chemical state during reaction has been proposed as oxides5, nitrides2, metallic, or surface nitride6. The proposed rate-limiting step has been the dissociation of N27–9, reaction of adsorbed nitrogen10, or desorption of NH311. Due to the vacuum requirement for surface-sensitive techniques, studies at reaction conditions are limited to theory computations12–14. We determined the surface composition, during NH3 production, at pressures up to 1 bar and temperatures as high as 723 K on flat, stepped Fe, and stepped Ru single crystal surfaces using operando X-ray Photoelectron Spectroscopy15. We found that all surfaces remain metallic. On Fe only a small amount of adsorbed N remains, yet Ru’s surface is almost adsorbate free. At 523 K, high amines (NHx) coverages appear on the stepped Fe surface. The results show that the rate-limiting step on Ru is always N2 dissociation. Still, on Fe the hydrogenation step involving adsorbed N atoms is essential for the total rate, as predicted by theory13. If the temperature is lowered on Fe, the rate-limiting steps switch and become surface species’ hydrogenation.

Today, fossil fuels still play a dominant role in the global energy systems. However, they are depleting quickly and the combustion of them causes many environmental concerns, including global warming, air pollution, ozone layer depletion, and acid rain. In response to these environmental challenges, a transition from fossil fuel energy sources towards sustainable alternatives is urgent and necessary. Unlike traditional fossil fuels, hydrogen serves as an environmentally friendly fuel with exceptional energy density, and its combustion generates no greenhouse gases. Moreover, hydrogen holds the versatility to be produced, stored, and utilized by various sectors, including transportation, industry, and electricity generation. Electrolyzer technology offers a sustainable pathway for clean hydrogen production when using electricity generated from renewable sources such as solar and wind power. The integration of hydrogen into energy systems holds significant potential for a decarbonized and sustainable future. In this thesis, we focused on creating affordable coatings using earth-abundant transition metals and explored their application as electrocatalysts for hydrogen and oxygen production in alkaline and acidic environments. We developed novel synthetic routes and new materials, we studied their intricate structure and composition, and we were able to fine-tune their catalytic activity and durability. Our findings demonstrated that plasma spray technology offers a scalable approach for producing highly active catalysts, while also developing coatings that can tolerate acidic environments and extend the lifetime of the state-of-the-art oxygen evolution catalysts. Furthermore, we tested and discussed alternative materials aiming to offer cost-effective substitutes for expensive Pt-based electrocatalysts for hydrogen production.

Human serum albumin (HSA) is the most prominent protein in blood plasma, responsible for the maintenance of blood viscosity and transport of endogenous and exogenous molecules. Fatty acids (FA) are the most common ligands of HSA and their binding can modify the protein's structure. The protein can assume two well-defined conformations, referred to as 'Neutral' and 'Basic'. The Neutral (N) state occurs at pH close to 7.0 and in the absence of bound FA. The Basic (B) state occurs at pH higher than 8.0 or when the protein is bound to long-chain FA. HSA's allosteric behaviour is dependent on the number on FA bound to the structure. However, the mechanism of this allosteric regulation is not clear. To understand how albumin changes its conformation, we compared a series of HSA structures deposited in the protein data bank to identify the minimum amount of FA bound to albumin, which is enough to drive the allosteric transition. Thereafter, non-biased molecular dynamics (MD) simulations were used to track protein's dynamics. Surprisingly, running an ensemble of relatively short MD simulations, we observed rapid transition from the B to the N state. These simulations revealed differences in the mobilities of the protein's subdomains, with one domain unable to fully complete its transition. To track the transition dynamics in full, we used these results to choose good geometrical collective variables for running metadynamics simulations. The metadynamics calculations showed that there was a low energy barrier for the transition from the B to the N state, while a higher energy barrier was observed for the N to the B transition. These calculations also offered valuable insights into the transition process. Human serum albumin (HSA) is an allosteric protein that can change conformation state through low energy barriers, being the most prominent protein in blood plasma, responsible for the maintenance of blood viscosity and transport of endogenous and exogenous molecules.

Cancers ultimately develop due to aberrations that involve proteins and modify their effects. Given that the structures of many proteinsinvolved in cancer pathogenesis are known, numerous studies have employed MD simulations in cancer research. In this chapter, somecauses and treatments for cancer are briefly introduced. Thereafter, systems where cancer development or therapy have been studied byMD simulations are described, focusing on contemporary subjects of interest. These include tumor cell metabolism, RAS proteins,driver mutations, allosteric inhibitors, kinetics of drug binding, activation of protein kinases and anticancer drug delivery. While notproviding a complete picture of the fields, these subjects allow the reader to understand what sorts of systems are studied, how, andwhich conclusions can be made with the help of MD simulations. This might help the interested reader to utilize such simulations forfurther studies in the field., Bidrag till encyklopedi

The multiple applications of lead halide perovskite materials and the extensive use of X-ray based techniques to characterize them highlight a need to understand their stability under X-ray irradiation. Here, we present a study where the X-ray stability of five different lead halide perovskite compositions (MAPbI3, MAPbCl3, MAPbBr3, FAPbBr3, CsPbBr3) was investigated using photoelectron spectroscopy. To exclude effects of thin film formation on the observed degradation behaviors, we studied clean surfaces of single crystals. Different X-ray resistance and degradation mechanisms were observed depending on the crystal composition. Overall, perovskites based on the MA+ cation were found to be less stable than those based on FA+ or Cs+. Metallic lead formed most easily in the chloride perovskite, followed by bromide, and only very little metallic lead formation was observed for MAPbI3. MAPbI3 showed one main degradation process, which was the radiolysis of MAI. Multiple simultaneous degradation processes were identified for the bromide compositions. These processes include ion migration towards the perovskite surface and the formation of volatile and solid products in addition to metallic lead. Lastly, CsBr formed as a solid degradation product on the surface of CsPbBr3., De två första författarna delar förstaförfattarskapet

Constructing a Z-scheme heterojunction with enhanced photocatalytic hydrogen evolution for graphitic carbon nitride-based (g-C3N4) composites is challenging because integrating g-C3N4 with other semiconductors, without specific band structure design, typically results in type I or type II heterojunctions. These heterojunctions have lower redox ability and limited enhancement in photocatalysis. Herein, we select highly crystalline carbon nitride (HCCN) as a proof-of-concept substrate. For the first time, we develop a AgBr nanosphere/HCCN composite photocatalyst that features an all -solid -state direct Z-scheme heterojunction for visible-light photocatalytic hydrogen evolution. The electron transfer mechanism is initially studied from the band structures and Fermi levels of HCCN and AgBr. It is subsequently confirmed by X-ray photoelectron spectroscopy (XPS), and electron microscopy. The close heterojunction contact and the built-in electron field of the Z-scheme heterojunction promote the migration and separation of photogenerated electrons and holes in the composite photocatalyst. Due to the redistribution of charge carriers, the photocatalyst shows superior redox capability and a markedly enhanced hydrogen evolution performance compared to its individual components. Combining all the advantages, AgBr nanosphere/HCCN reached an apparent quantum efficiency (AQE) of 6 % under the illumination of 410 nm, which is 4 times higher than that of the single HCCN component.

Theoretical predictions of the solubilizing capacity of micelles and vesicles present in intestinal fluid are important for the development of new delivery techniques and bioavailability improvement. A balance between accuracy and computational cost is a key factor for an extensive study of numerous compounds in diverse environments. In this study, we aimed to determine an optimal molecular dynamics (MD) protocol to evaluate small-molecule interactions with micelles composed of bile salts and phospholipids. MD simulations were used to produce free energy profiles for three drug molecules (danazol, probucol, and prednisolone) and one surfactant molecule (sodium caprate) as a function of the distance from the colloid center of mass. To address the challenges associated with such tasks, we compared different simulation setups, including freely assembled colloids versus pre-organized spherical micelles, full free energy profiles versus only a few points of interest, and a coarse-grained model versus an all-atom model. Our findings demonstrate that combining these techniques is advantageous for achieving optimal performance and accuracy when evaluating the solubilization capacity of micelles.Graphical abstractAll-atom (AA) and coarse-grained (CG) umbrella sampling (US) simulations and point-wise free energy (FE) calculations were compared to their efficiency to computationally analyze the solubilization of active pharmaceutical ingredients in intestinal fluid colloids.

The effects of polyethylene glycol- (PEG) modified lipids and gangliosides on the Ca2+ induced interaction between liposomes composed of palmitoyl-oleoyl phosphatidylethanolamine (POPE) and palmitoyl-oleoyl phosphatidylserine (POPS) was investigated at physiological ionic strength. Förster resonance energy transfer (FRET) studies complemented with dynamic light scattering (DLS) and cryo-transmission electron microscopy (Cryo-EM) show that naked liposomes tend to adhere, rupture, and collapse on each other's surfaces upon addition of Ca2+, eventually resulting in the formation of large multilamellar aggregates and bilayer sheets. Noteworthy, the presence of gangliosides or PEGylated lipids does not prevent the adhesion-rupture process, but leads to the formation of small, long-lived bilayer fragments/disks. PEGylated lipids seem to be more effective than gangliosides at stabilizing these structures. Attractive interactions arising from ion correlation are proposed to be a driving force for the liposome-liposome adhesion and rupture processes. The results suggest that, in contrast with the conclusions drawn from previous solely FRET-based studies, direct liposome-liposome fusion is not the dominating process triggered by Ca2+ in the systems studied.

The self-induced formation of core-shell InAlN nanorods (NRs) is addressed at the mesoscopic scale by density functional theory (DFT)-resulting parameters to develop phase field modeling (PFM). Accounting for the structural, bonding, and electronic features of immiscible semiconductor systems at the nanometer scale, we advance DFT-based procedures for computation of the parameters necessary for PFM simulation runs, namely, interfacial energies and diffusion coefficients. The developed DFT procedures conform to experimental self-induced InAlN NRs' concerning phase-separation, core/shell interface, morphology, and composition. Finally, we infer the prospects for the transferability of the coupled DFT-PFM simulation approach to a wider range of nanostructured semiconductor materials., Funding Agencies|Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials (AFM) at Linkoping University [2009-00971]; Wallenberg Scholar Program Grant [KAW 2019.0290]; Swedish Research Council (Vetenskapsradet) [2018-04198]; Swedish Energy Agency (Energimyndigheten) [46658-1]; Brazilian Research agency CNPq; Brazilian Research agency CAPES; National Science Foundation (NSF) of the USA [CAREER-2145812]; Swedish Research Council [NAISS 2023/5-116, NAISS 2023/23-161]

In organic photovoltaic cells, the solution-aggregation effect (SAE) is long considered a critical factor in achieving high power-conversion efficiencies for polymer donor (PD)/non-fullerene acceptor (NFA) blend systems. However, the underlying mechanism has yet to be fully understood. Herein, based on an extensive study of blends consisting of the representative 2D-benzodithiophene-based PDs and acceptor-donor-acceptor-type NFAs, it is demonstrated that SAE shows a strong correlation with the aggregation kinetics during solidification, and the aggregation competition between PD and NFA determines the phase separation of blend film and thus the photovoltaic performance. PDs with strong SAEs enable earlier aggregation evolutions than NFAs, resulting in well-known polymer-templated fibrillar network structures and superior PCEs. With the weakening of PDs' aggregation effects, NFAs, showing stronger tendencies to aggregate, tend to form oversized domains, leading to significantly reduced external quantum efficiencies and fill factors. These trends reveal the importance of matching SAE between PD and NFA. The aggregation abilities of various materials are further evaluated and the aggregation ability/photovoltaic parameter diagrams of 64 PD/NFA combinations are provided. This work proposes a guiding criteria and facile approach to match efficient PD/NFA systems. A systematic study of the representative organic photovoltaic systems shows that the aggregation competition between polymer donor (PD) and non-fullerene acceptor (NFA) is a decisive factor in the phase separation of blend film and thus the photovoltaic performance. Based on 64 PD/NFA combinations, the aggregation ability/photovoltaic parameter heatmaps are plotted, providing a new matching rule for developing high-efficiency PD/NFA systems. image, Funding Agencies|National Natural Science Foundation of China; Jiangsu Provincial Departments of Science and Technology [BK20220010, BE2022023]; Natural Science Foundation of Jiangsu Province [BK20221317]; Science and Technology Development Fund, Macao SAR [FDCT-0082/2021/A2]; UM's research fund [MYRG2022-00241-IAPME, MYRG-CRG2022-00009-FHS]; [52273295]; [52303236]; [61935017]; [51903239]; [62288102]; [62175268]

The properties and applications of ionic liquids (ILs) have been widely investigated when they are confined within nanochannels such as carbon nanotubes (CNTs). The confined ILs exhibit very different properties from their bulk state due to a nanoconfinement effect, which plays an important role in the performances of devices with ILs. In this work, we studied the effect of the charge carried by CNTs on confined ILs inside CNTs using molecular dynamics simulations. In charged CNTs, cations and anions are distributed separately along the radial directions, and the transition of orientations of the cations between parallel and vertical to CNTs occurs by changing the charge state of CNTs. The number of hydrogen bonds (HBs) formed by the confined ILs can be reduced by switching the surface charge of CNTs from positive to negative due to the contact modes between cations and anions as well as the distributions of cations in CNTs. The diffusivities along and vertical to the axial direction of CNTs were found to be non-monotonic owing to the "trade-off" effect from both ion pair interlocking and anchoring ILs on the CNT walls. Additionally, the region-dependent dynamics of ILs were also related to the intermolecular interactions in different regions of CNTs. Furthermore, the vibrational modes of ILs were obviously influenced in highly charged CNTs as determined by calculating the density of vibrational states, which demonstrated the transitions in the structure and interactions. The density distributions changed from single layer to double layers when increasing the pore size of neutral CNTs while the hydrogen bonds exhibited a non-monotonic tendency versus the pore sizes. Our results might help to understand the structure and dynamics of confined ILs as well as aid optimizing the performance of devices with ILs. Exploration of the impact of charge states of carbon nanotubes on region-dependent properties of confined ionic liquids and the relation between ionic dynamics an, Funding Agencies|Basic and Applied Basic Research Foundation of Guangdong Province [2022A1515010873, 2023A1515012535]; Guangdong Basic and Applied Basic Research Foundation [22003080]; National Natural Science Foundation of China

Enabling green-solvent-processed large-area organic solar cells (OSCs) is of great significance to their industrialization. However, precisely controlling the temperature-dependent fluid mechanics and evaporation behavior of green solvents with high-boiling points is challenging. Controlling these parameters is essential to prevent the non-uniform distribution of active layer components and severe molecule aggregation, which collectively degrade the power conversion efficiency (PCE) of large-scale devices. In this study, we revealed that the temperature gradient distribution across a wet film is the root of the notorious Marangoni effect, which leads to the formation of a severely non-uniform active layer on a large scale. Thus, a rapid solidification strategy was proposed to accelerate the evaporation of toluene, a green solvent, at room temperature. This strategy simultaneously inhibits the Marangoni effect and suppresses molecular aggregation in the wet film, allowing the formation of a nano-scale phase separation active layer with uniform morphology. The resultant toluene-processed 15.64-cm2 large-area OSC module achieves an outstanding PCE of 16.03% (certified: 15.69%), which represents the highest reported PCE of green-solvent-processed OSC modules. Notably, this strategy also exhibits a weak scale dependence on the PCE, and we successfully achieved a state-of-the-art PCE of 14.45% for a 72.00-cm2 OSC module. A rapid solidification strategy was developed for simultaneously avoiding the Marangoni effect and suppressing molecular aggregation. The resultant 15.64 cm2 large-area OSC module exhibited a record power conversion efficiency of 16.03%., Funding Agencies|Priority Academic Program Development of Jiangsu Higher Education Institutions [52325307, 52273188, 22075194, 22309129]; National Natural Science Foundation of China [20KJA430010]; Natural Science Foundation of the Jiangsu Higher Education Institutions of China; Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD); Collaborative Innovation Center of Suzhou Nano Science and Technology [2023NSFSC0990]; Key Laboratory of Polymeric Materials Design and Synthesis for Biomedical Function, Soochow University, Sichuan Science and Technology Program [DE-AC02-05CH11231]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy; Shanghai Synchrotron Radiation Facility (SSRF)

High-boiling-point nonhalogenated solvents are superior solvents to produce large-area organic solar cells (OSCs) in industry because of their wide processing window and low toxicity; while, these solvents with slow evaporation kinetics will lead excessive aggregation of state-of-the-art small molecule acceptors (e.g. L8-BO), delivering serious efficiency losses. Here, a heterogeneous nucleating agent strategy is developed by grafting oligo (ethylene glycol) side-chains on L8-BO (BTO-BO). The formation energy of the obtained BTO-BO; while, changing from liquid in a solvent to a crystalline phase, is lower than that of L8-BO irrespective of the solvent type. When BTO-BO is added as the third component into the active layer (e.g. PM6:L8-BO), it easily assembles to form numerous seed crystals, which serve as nucleation sites to trigger heterogeneous nucleation and increase nucleation density of L8-BO through strong hydrogen bonding interactions even in high-boiling-point nonhalogenated solvents. Therefore, it can effectively suppress excessive aggregation during growth, achieving ideal phase-separation active layer with small domain sizes and high crystallinity. The resultant toluene-processed OSCs exhibit a record power conversion efficiency (PCE) of 19.42% (certificated 19.12%) with excellent operational stability. The strategy also has superior advantages in large-scale devices, showing a 15.03-cm2 module with a record PCE of 16.35% (certificated 15.97%). The heterogeneous nucleating agent (BTO-BO) is developed to suppress the excessive aggregation of L8-BO in high-boiling-point nonhalogenated solvents processing, achieving the active layer with high crystallinity and nano-scaled phase separation morphology. The resultant OSCs achieve record power conversion efficiencies of 19.42% (0.062-cm2) and 16.35% (15. 03-cm2) with excellent operational stabilities. image, Funding Agencies|National Natural Science Foundation of China; National Postdoctoral Program for Innovative Talents [BX20220221]; China Postdoctoral Science Foundation [2023M732530]; Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) the Collaborative Innovation Center of Suzhou Nano Science and Technology; Key Laboratory of Polymeric Materials Design and Synthesis for Biomedical Function, Soochow University; Office of Science, Office of Basic Energy Sciences of the US Department of Energy [DE-AC02-05CH11231]; [52325307]; [52273188]; [22309129]; [22075194]

Due to the high exciton binding energy and relatively low charge carrier mobilities of organic photovoltaic materials, it is crucial to optimize the active layer morphology of organic solar cells (OSCs) to well juggle exciton dissociation and charge carrier transport, and inhibit charge carrier recombination for high power conversion efficiencies (PCEs). Herein, we efficiently improve the crystallinity and miscibility of fused ring electron acceptors (FREAs) via lengthening the side chains and developing four FREAs, BTP-nC8, BTP-C8, BTP-C12 and BTP-C20. The dual functions of lengthening the side chains of FREAs make PM6:FREA blend films present the tendency of first improving then deteriorating in crystallinity, phase separation, domain purity and thus charge carrier dynamics, which leads the JSC and FF of PM6:FREA-based OSCs to show the same trend along with the side-chain length of FREAs. More importantly, enhancing the miscibility between PM6 and FREA facilitates the spatial registry to reduce the formation and recombination rate of triplet excitons in the PM6:FREA blend films, thus inhibiting the non-radiative recombination for decreased Delta Enr, and then increasing VOC in OSCs. Among them, PM6:BTP-C8 based OSCs well balance the multiple impacts of lengthening the side chains to achieve the highest PCE of 17.77%. This work demonstrates that it is important to finely control the crystallinity and miscibility of organic photovoltaic materials to achieve high PCEs in OSCs. The miscibility and crystallinity of fused ring electron acceptors is regulated to study the effects on the morphology and energy loss of organic solar cells (OSCs). BTP-C8 based OSCs juggle multiple impacts to gain the best efficiency., Funding Agencies|Natural Science Foundation of Hunan Province [52372056, 52272056, 52232003]; National Natural Science Foundation of China [2023RC3044]; Science and Technology Innovation Program of Hunan Province [2022JJ40570]; Natural Science Foundation of Hunan Province [DE-AC02-05CH11231]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy

The key factor restricting the power conversion efficiency (PCE) of organic solar cells (OSCs) is the energy loss (Eloss), which is the difference between the optical bandgap (Eg) of the active layer and open-circuit voltage (VOC) of the device. To achieve lower Eloss, it is necessary to obtain an appropriate donor-acceptor phase separation size to accelerate exciton dissociation and inhibit the recombination process. However, in most high-efficiency non-fullerene systems, acceptors often exhibit excessive aggregation phenomena. The decrease in the interface area leads to a decrease in exciton dissociation efficiency, which increases the energy loss. Herein, we report a ternary strategy to decrease the crystallization time of the acceptor and inhibit the excessive aggregation condition of a non-fullerene acceptor. We chose a donor poly{[4,8-bis[5-(2-ethylhexyl)-4-fluoro-2-thienyl]benzo[1,2-b:4,5-b ']-dithiophene-2,6-diyl]-alt-[2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c ']dithiophene-1,3-diyl]]} (PM6) and a non-fullerene acceptor (2,2 '-((2Z,2 ' Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2 '',3 '':4 ',5 ']thieno[2 ',3 ':4,5]pyrrolo[3,2-g]thieno[2 ',3 ':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile) (Y6) as the model system. Y6 is prone to forming a tightly packed structure due to its planar curved skeleton. To suppress the excessive aggregation, we chose poly[2,2 '-((2Z,2 ' Z)-((12,13-bis(2-octyldodecyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2 '',3 '':4 ',5 ']thieno[2 ',3 ':4,5]pyrrolo[3,2-g]thieno[2 ',3 ':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile-co-2,5-thiophene] (PY-IT) as a second acceptor, which has good compatibility with Y6. By using in situ UV-visible absorption spectroscopy to monitor the f, Funding Agencies|National Natural Science Foundation of China [2022YFB4200400, 2019YFA0705900]; Ministry of Science and Technology [51933010, 52003269, 52394274]; National Natural Science Foundation of China

Complex components for high-temperature gas turbine applications require materials that offer a combination of excellent high-temperature strength and oxidation resistance. Nickel-based superalloys with high gamma prime (gamma)' volume fractions are particularly suited for these applications, especially combined with additive manufacturing for intricate geometries. Despite the complex thermal history that these materials experience during laser powder bed fusion (LPBF) processing, gamma'formation is suppressed when manufacturing IN738LC, which has a medium equilibrium gamma'content of about 40-50 vol%. This study follows gamma'formation in LPBF IN738LC during subsequent annealing treatments at temperatures ranging from 745 C-degrees to 865 C-degrees, creating an experimentally determined TTT (temperature-time-transformation) diagram. This diagram is largely based on scanning electron microscopy (SEM) imaging supported by Vickers hardness measurements and scanning transmission electron microscopy (STEM) bright field imaging. Atom probe tomography (APT) of the as-built material indicated nm-sized regions depleted in Cr and enriched in Ni, Al, and Ti, but show no characteristic superlattice patterns in TEM diffraction. APT and TEM diffraction analysis of material annealed at 850 C for 3 min confirmed the presence of the gamma'phase but indicated that gamma'had formed through spinodal decomposition instead of precipitation., Funding Agencies|Swedish Governmental Agency of Innovation Systems (Vinnova); Area of Advance Production at Chalmers

The effect of different Mo/W ratios of three single crystal nickel base superalloys on the oxidation behavior was investigated at 1100 degrees C. Both isothermal and cyclic oxidation tests showed that increasing Mo/W ratio corresponds to lower weight change and improved resistance. The microscopic observation uncovers that the harmful effect of Mo is limited by the dense Al2O3 scale. In contrast, excessive W leads to fast growth of interlayer and its premature spallation. This research proposes and verifies a new way to improve oxidation resistance of alloy, namely, balancing the harmful effect of refractory elements., Funding Agencies|National Key Research and Development Program of China [2018YFB0704100]; Taishan Scholars Program of Shandong Province [tsqn201909081]; Key R & D Program of Guangdong Province, China [2019B010943001]; State Key Laboratory of Powder Metallurgy, Central South University, Changsha, China