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Ternary pnictide semiconductors with II-IV-V2 stoichiometry hold potential as cost-effective thermoelectric materials with suitable electronic transport properties, but their lattice thermal conductivities (κ) are typically too high. Insights into their vibrational properties are therefore crucial to finding strategies to reduce κ and achieve improved thermoelectric performance. We present a theoretical exploration of the lattice thermal conductivities for a set of pnictide semiconductors with ABX2 composition (A = Zn, Cd; B = Si, Ge, Sn; and X = P, As) using machine-learning-based regression algorithms to extract force constants from a reduced number of density functional theory simulations and then solving the Boltzmann transport equation for phonons. Our results align well with available experimental data, decreasing the mean absolute error by ∼3 W m-1 K-1 with respect to the best previous set of theoretical predictions. Zn-based ternary pnictides have, on average, more than double the thermal conductivity of the Cd-based compounds. Anisotropic behavior increases with the mass difference between A and B cations, but while the nature of the anion does not affect the structural anisotropy, the thermal conductivity anisotropy is typically higher for arsenides than for phosphides. We identify compounds such as CdGeAs2, for which nanostructuring to an affordable range of particle sizes could lead to κ values low enough for thermoelectric applications.

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Using a combination of experiments and calculations, we have gained new insights into the nature of anion-cation interactions in ionic liquids (ILs). An X-ray photoelectron spectroscopy (XPS)-derived anion-dependent electrostatic interaction strength scale, determined using XPS core-level binding energies for IL cations, is presented here for 39 different anions, with at least 18 new anions included. Linear correlations of experimental XPS core-level binding energies for IL cations with (a) calculated core binding energies (ab initio molecular dynamics (AIMD) simulations were used to generate high-quality model IL structures followed by single-point density functional theory (DFT) to obtain calculated core binding energies), (b) experimental XPS core-level binding energies for IL anions, and (c) other anion-dependent interaction strength scales led to three main conclusions. First, the effect of different anions on the cation can be related to ground-state interactions. Second, the variations of anion-dependent interactions with the identity of the anion are best rationalized in terms of electrostatic interactions and not occupied valence state/unoccupied valence state interactions or polarizability-driven interactions. Therefore, the XPS-derived anion-dependent interaction strength scale can be explained using a simple electrostatic model based on electrostatic site potentials. Third, anion-probe interactions, irrespective of the identity of the probe, are primarily electrostatic, meaning that our electrostatic interaction strength scale captures some inherent, intrinsic property of anions independent of the probe used to measure the interaction strength scale.

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The significance of interfacial thermal resistance in the thermal conductivity of nanofluids is not well understood, in part because of the absence of measurements of this quantity. Here, we study the interfacial thermal resistance for metal-oil nanofluids of interest as heat transfer fluids for concentrating solar power, using density functional theory and molecular dynamics simulations. Insights on the role of chemical interactions in determining the interfacial thermal resistance are revealed. The results presented here showcase a general picture in which the stronger the chemical interactions between species at the interface, the lower the associated interfacial thermal resistance. The implications toward nanofluid design are discussed. We show that, for this important family of metal-oil nanofluids, the interfacial thermal resistance values are low enough so that it is possible to afford a reduction in particle size, minimizing stability and rheological issues while still offering enhancement in the effective thermal conductivity with respect to the base fluid.

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Hydrogen bonds (HBs) play an important role in the rotational dynamics of organic cations in hybrid organic/inorganic halide perovskites, thus affecting the structural and electronic properties of the perovskites. However, the properties and even the existence of HBs in these perovskites are not well established. In this study, we investigate HBs in perovskites MAPbBr3 (MA+ = CH3NH3+), FAPbI3 (FA+ = CH(NH2)2+), and their solid solution with composition (FAPbI3)7/8(MAPbBr3)1/8, using ab initio molecular dynamics and electronic structure calculations. We consider HBs donated by X-H fragments (X = N and C) of the organic cations and accepted by the halides (Y = Br and I) and characterize their properties based on pair distribution functions and on a combined distribution function of the hydrogen-acceptor distance with the donor-hydrogen-acceptor angle. By analyzing these functions, we establish geometrical criteria for HB existence based on the hydrogen-acceptor (H-Y) distance and donor-hydrogen-acceptor angle (X-H-Y). The distance condition is defined as d(H - Y) < 3 Å for N-H-donated HBs and d(H - Y) < 4 Å for C-H-donated HBs. The angular condition is 135° < (X - H - Y) < 180° for both types of HBs. A HB is considered to be formed when both angular and distance conditions are simultaneously satisfied. At the simulated temperature (350 K), the HBs dynamically break and form. We compute the time correlation functions of HB existence and HB lifetimes, which range between 0.1 and 0.3 ps at that temperature. The analysis of HB lifetimes indicates that N-H-Br bonds are relatively stronger than N-H-I bonds, while C-H-Y bonds are weaker, with a minimal influence from the halide and cation. To evaluate the impact of HBs on the vibrational spectra, we present the power spectrum in the region of N-H and C-H stretching modes, comparing them with the normal mode frequencies of isolated cations. We show that the peaks associated with N-H stretching modes in perovskites are redshifted and asymmetrically deformed, while the C-H peaks do not exhibit these effects.

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Using grand canonical thermodynamic analysis with inputs from DFT calculations we calculated equilibrium molar fractions of copper vacancies (VCu), H interstitials (Hi) and their complexes in bulk Cu in a wide range of temperature and hydrogen pressure values. The results show that the equilibrium molar fractions of both VCu and Hi are low in most conditions of interest, in good agreement with available experimental data. Although Hi-VCu complexes have significantly lower formation energies than the isolated defects, the low molar fraction of H is predicted to have little impact on the rise in vacancy molar fraction for external hydrogen pressures below 100 bar. Only at relatively high hydrogen pressures exceeding 10 kbar in the presence of Cu vacancies, the H molar fraction was found to reach the same order of magnitude as the molar fraction of vacancies. These results put thermodynamic limits on the hydrogen-induced vacancy clustering and void formation in bulk Cu.

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MOF@Biomass layered hybrids were designed through in situ growth from rice husk (RH) and microwave-assisted synthesized MIL-53(Al) particles that enable the reduction of reaction times. The synthesis process included steps to pretreat RH, Al adsorption on RH, and then MIL-53(Al) in-situ growth reaction at 125 °C for 60 min and 200 W irradiation power. The resulting hybrid (MIL-53(Al)@RH) and its parent separate materials were characterized using TGA, SEM, FTIR, XRD, among others. MIL-53(Al)@RH showed high crystallinity in the hybridized MOF particles, thermal decomposition phases, and functional groups (Al-O, O-H, CO, and CC). The hybrid particles allow an easy separation during heterogeneous processing due to their 400 times larger size compared to MIL-53(Al) crystals. The properties of the layered hybrids for removal of Oxytetracycline (OTC), Diclofenac (DCL), and Glyphosate (GLY) in aqueous solutions, were tested by adsorption (ADS) and advanced oxidation processes (AOP). The high ADS capacities (162 mg g-1 GLY, 139 mg g-1 OTC, 93 mg g-1 DCL) and % removal in AOP (97% GLY, 91% OTC, 80% DCL) demonstrated that MIL-53(Al) maintained its properties after hybridization.

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We demonstrate a combined experimental and computational approach to probe the electronic structure and atomic environment of an ionic liquid, based on core level binding energies. The 1-butyl-3-methylimidazolium thiocyanate [C4C1Im][SCN] ionic liquid was studied using ab initio molecular dynamics, and results were compared against previously published and new experimental X-ray photoelectron spectroscopy (XPS) data. The long-held assumption that initial-state effects in XPS dominate the measured binding energies is proven correct, which validates the established premise that the ground state electronic structure of the ionic liquid can be inferred directly from XPS measurements. A regression model based upon site electrostatic potentials and intramolecular bond lengths is shown to account accurately for variations in core-level binding energies within the ionic liquid, demonstrating the important effect of long-range interactions on the core levels and throwing into question the validity of traditional single ion pair ionic liquid calculations for interpreting XPS data.

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Abstract Introduction/Objetive: Work orientation includes the individual's beliefs regarding the role of work in his/her life as a whole and what they are searching for in their careers. There are three types of orientation to work: job, career, and vocation. Work orientation has the distinction of examining how work connects with people's lives and is, therefore, an appropriate construct for evaluating the impact of work on human flourishing. The aims of this study are first to explore work orientation in twelve Ibero-American countries; and second, to investigate whether work orientation affects flourishing in the lives of adults in twelve Ibero-American countries. Method: A total of 3000 adults participated in this study. The University of Pennsylvania Work-Life Questionnaire was used to evaluate the type of relationship that employees reported having with their work, according to the distinctions between job, career, and calling. A 12-item version of the Multidimensional Flourishing Scale was used to measure three aspects of flourishing: social, psychological, and emotional well-being. Results: Most participants reported a high level of calling in their work orientation. In most countries, those with a calling orientation reported higher levels of social and psychological well-being than those with a job orientation. The results indicate a clear relationship between a calling orientation and social and psychological well-being. Conclusion: This research is the first to compare the relationship between work-orientation and flourishing in Ibero-America. The findings help us understand that work-orientation is not a secondary aspect of a person's life but has fundamental implications in the lives of workers.

Resumen Introducción/Objetivo: La orientación laboral incluye las creencias del individuo sobre el papel del trabajo en su vida como un todo y lo que está buscando en su carrera. La orientación laboral examina cómo el trabajo se conecta con la vida de las personas y es un constructo apropiado para evaluar el efecto del trabajo en el florecimiento humano. Se propone explorar la orientación laboral en 12 países iberoamericanos; e investigar si la orientación laboral afecta el florecimiento humano. Método: Tres mil adultos participaron en este estudio. Se utilizó el Work-Life Questionnaire para evaluar el tipo de relación que los empleados informan tener con su trabajo, de acuerdo con las distinciones entre trabajo, carrera y vocación. Se utilizó la Escala de Florecimiento Multidimensional para medir tres aspectos del florecimiento: bienestar social, psicológico y emocional. Resultados: La mayoría de los participantes informaron un alto nivel de orientación laboral como vocación. En la mayoría de los países, aquellos que trabajan por vocación informaron niveles más altos de bienestar social y psicológico que aquellos que trabajan solo por una motivación económica. Conclusiones: Esta investigación es la primera en comparar la relación entre la orientación al trabajo y el florecimiento humano en Iberoamérica. Los hallazgos nos ayudan a comprender que la orientación al trabajo no es un aspecto secundario de la vida de una persona, sino que tiene implicaciones fundamentales en los trabajadores.

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The dearth of n-type sulfides with thermoelectric performance comparable to that of their p-type analogues presents a problem in the fabrication of all-sulfide devices. Chalcopyrite (CuFeS2) offers a rare example of an n-type sulfide. Chemical substitution has been used to enhance the thermoelectric performance of chalcopyrite through preparation of Cu1-x Sn x FeS2 (0 ≤ x ≤ 0.1). Substitution induces a high level of mass and strain field fluctuation, leading to lattice softening and enhanced point-defect scattering. Together with dislocations and twinning identified by transmission electron microscopy, this provides a mechanism for scattering phonons with a wide range of mean free paths. Substituted materials retain a large density-of-states effective mass and, hence, a high Seebeck coefficient. Combined with a high charge-carrier mobility and, thus, high electrical conductivity, a 3-fold improvement in power factor is achieved. Density functional theory (DFT) calculations reveal that substitution leads to the creation of small polarons, involving localized Fe2+ states, as confirmed by X-ray photoelectron spectroscopy. Small polaron formation limits the increase in carrier concentration to values that are lower than expected on electron-counting grounds. An improved power factor, coupled with substantial reductions (up to 40%) in lattice thermal conductivity, increases the maximum figure-of-merit by 300%, to zT ≈ 0.3 at 673 K for Cu0.96Sn0.04FeS2.

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The term metabolic-associated fatty liver disease (MAFLD) has been proposed to define positively fatty liver disease in the form associated with metabolic risk factors. The aim of this study was to assess the dietary intake of MAFLD and explore a possible relationship between its inflammatory characteristics (assessed by Dietary Inflammatory Index-DII®), the degree of liver fibrosis (assessed by transient elastography), and the amount of alcohol intake. MAFLD patients were included (n = 161) and were classified, according to the amount of alcoholic intake, as MAFLD without alcohol intake (n = 77) and MAFLD with alcohol intake (n = 84), with 19 presenting harmful alcoholic consumption. Dietary intake was 1868 ± 415 kcal/day and did not present differences in energy or nutrient intake based on the presence of metabolic comorbidities. Patients with MAFLD and alcohol intake consumed significantly more energy and presented a tendency for higher intake of carbohydrates and sugar. Patients with harmful alcohol intake presented a higher intake of total fat and cholesterol compared with moderate alcohol intake. There were no differences in DII® based on fibrosis severity or the amount of alcohol consumption. This work contributes to the characterization of baseline dietary intake in MAFLD patients, paving the way to design more suited dietary interventional trials.

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Cow's milk is currently the most consumed product worldwide. However, due to various direct and indirect contamination sources, different chemical and microbiological contaminants have been found in cow's milk. This review details the main contaminants found in cow's milk, referring to the sources of contamination and their impact on human health. A comparative approach highlights the poor efficacy and effects of the pasteurization process with other methods used in the treatment of cow's milk. Despite pasteurization and related techniques being the most widely applied to date, they have not demonstrated efficacy in eliminating contaminants. New technologies have appeared as alternative treatments to pasteurization. However, in addition to causing physicochemical changes in the raw material, their efficacy is not total in eliminating chemical contaminants, suggesting the need for new research to find a solution that contributes to improving food safety.

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Molecular perovskites, i.e. ABX3 coordination polymers with a perovskite structure, are a chemically diverse material platform for studying fundamental and applied materials properties such as barocalorics and improper ferroelectrics. Compared to inorganic perovskites, the use of molecular ions on the A- and X-site of molecular perovskites leads to new geometric and structural degrees of freedom. In this work we introduce the concept of tilt and shift polymorphism, categorising irreversible perovskite-to-perovskite phase transitions in molecular perovskites. As a model example we study the new molecular perovskite series [(nPr)3(CH3)N]M(C2N3)3 with M = Mn2+, Co2+, Ni2+, and nPr = n-propyl, where different polymorphs crystallise in the perovskite structure but with different tilt systems depending on the synthetic conditions. Tilt and shift polymorphism is a direct ramification of the use of molecular building units in molecular perovskites and as such is unknown for inorganic perovskites. Given the role of polymorphism in materials science, medicine and mineralogy, and more generally the relation between physicochemical properties and structure, the concept introduced herein represents an important step in classifying the crystal chemistry of molecular perovskites and in maturing the field.

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Sulfur and molybdenum trace impurities in speleothems (stalagmites and stalactites) can provide long and continuous records of volcanic activity, which are important for past climatic and environmental reconstructions. However, the chemistry governing the incorporation of the trace element-bearing species into the calcium carbonate phases forming speleothems is not well understood. Our previous work has shown that substitution of tetrahedral oxyanions [XO4]2- (X = S and Mo) replacing [CO3]2- in CaCO3 bulk phases (except perhaps for vaterite) is thermodynamically unfavorable with respect to the formation of competing phases, due to the larger size and different shape of the [XO4]2- tetrahedral anions in comparison with the flat [CO3]2- anions, which implied that most of the incorporation would happen at the surface rather than at the bulk of the mineral. Here, we present an ab initio molecular dynamics study, exploring the incorporation of these impurities at the mineral-water interface. We show that the oxyanion substitution at the aqueous calcite (10.4) surface is clearly favored over bulk incorporation, due to the lower structural strain on the calcium carbonate solid. Incorporation at surface step sites is even more favorable for both oxyanions, thanks to the additional interface space afforded by the surface line defect to accommodate the tetrahedral anion. Differences between sulfate and molybdate substitutions can be mostly explained by the size of the anions. The molybdate oxyanion is more difficult to incorporate in the calcite bulk than the smaller sulfate oxyanion. However, when molybdate is substituted at the surface, the elastic cost is avoided because the oxyanion protrudes out of the surface and gains stability via the interaction with water at the interface, which in balance results in more favorable surface substitution for molybdate than for sulfate. The detailed molecular-level insights provided by our calculations will be useful to understand the chemical basis of S- and Mo-based speleothem records.

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Strongyloidiasis is an infection caused by Strongyloides stercoralis. Gastrointestinal manifestations typically include duodenitis, chronic enterocolitis, and malabsorption, while gastric involvement is very rare. In this case report, the -authors present a case of upper gastrointestinal bleeding caused by a gastric ulcer with a challenging etiological diagnosis. In Portugal, there have been reports in the past century of autochthonous cases of S. stercoralis infection suggesting endemic zones, but with the current sanitation infrastructure strongyloidiasis is thought to be rare. A 56-year-old Caucasian male smoker with a history of significant weight loss presented to the emergency department with hema-temesis and abdominal pain. Upper endoscopy revealed a giant gastric ulcer with a macroscopic appearance suggestive of malignancy. Further investigation with CT scan highlighted gastric wall thickness and a spiculated lung lesion in the upper right lobe without lymph node involvement or metastatic disease. Bronchoscopy with bronchial brushing was performed. Histological examination identified squamous cell carcinoma of the lung and the patient was referred to Oncological Pneumology. Gastric ulcer biopsies ruled out malignancy and identified fragments of nematodes with inflammatory infiltrates and fibrinogranulocytic exudate, suggestive of S. stercoralis. Accordingly, the diagnosis of strongyloidiasis was made and further confirmed with molecular methods and serology. The giant gastric ulcer was affirmed to be caused by S. stercoralis infection and the patient was treated with ivermectin with improvement of epigastric pain. On reevaluation 6 weeks later the patient was asymptomatic, had gained weight, parasitological stool examinations were negative, and upper endoscopy showed complete ulcer healing. Further tests were done targeting risk factors for strongyloidiasis, and in addition to the presence of malignancy, other underlying causes for immunosuppression were ruled out. In this case report strongyloidiasis was manifested by gastric involvement with upper gastrointestinal bleeding in a patient who was subsequently diagnosed with squamous cell carcinoma of the lung.

A estrongiloidíase é uma infecção causada por Strongyloides stercoralis. As manifestações gastrointestinais tipicamente incluem duodenite, enterocolite crónica e má absorção, sendo o envolvimento gástrico muito raro. Neste caso clínico, os autores apresentam um caso de hemorragia digestiva alta causada por uma úlcera gástrica com um diagnóstico etiológico desafiante. Em Portugal no século passado existiram casos autóctones de infecção a S. stercoralis sugerindo zonas endémicas, mas com a actual infraestrutura de saneamento a estrongiloidíase é rara. Homem de 56 anos de idade, caucasiano, fumador, com história de perda ponderal significativa, admitido no Serviço de Urgência por hematemeses e dor abdominal. A endoscopia digestiva alta realizada revelou uma úlcera gástrica gigante com aparência macroscópica sugestiva de malignidade. A investigação subsequente com tomografia computadorizada (TC) destacou a presença de espessamento gástrico e uma lesão pulmonar espiculada no lobo superior direito, sem envolvimento ganglionar ou doença metastática. Foi realizada broncofibroscopia com escovado brônquico tendo o exame histológico identificado carcinoma pavimento celular do pulmão, pelo que o doente foi referenciado para a Pneumologia Oncológica. As biópsias da úlcera gástrica descartaram malignidade e identificaram fragmentos de nemátodes com infiltrados inflamatórios e exsudado fibrino-granulocítico, sugestivo de Strongyloides stercoralis. Consequentemente, foi feito o diagnóstico de estrongiloidíase, confirmado com métodos moleculares e sorologia. Admitiu-se que a úlcera gástrica gigante terá sido causada pela infecção por Strongyloides stercoralis e o doente foi tratado com ivermectina com melhoria da dor epigástrica. Em reavaliação, seis semanas depois, o doente estava assintomático, com ganho ponderal, os exames parasitológicos das fezes estavam negativos e a endoscopia digestiva alta mostrou cicatrização completa da úlcera. Foram realizados exames adicionais para investigação de factores de risco para estrongiloidíase, tendo sido excluídas outras causas de imunossupressão subjacente para além da presença de malignidade. Neste caso clínico, a estrongiloidíase manifestou-se por envolvimento gástrico com hemorragia digestiva alta num doente que foi posteriormente diagnosticado com carcinoma pavimento celular do pulmão.

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Computer simulations of alloys' properties often require calculations in a large space of configurations in a supercell of the crystal structure. A common approach is to map density functional theory results into a simplified interaction model using so-called cluster expansions, which are linear on the cluster correlation functions. Alternative descriptors have not been sufficiently explored so far. We show here that a simple descriptor based on the Coulomb matrix eigenspectrum clearly outperforms the cluster expansion for both total energy and bandgap energy predictions in the configurational space of a MgO-ZnO solid solution, a prototypical oxide alloy for bandgap engineering. Bandgap predictions can be further improved by introducing non-linearity via gradient-boosted decision trees or neural networks based on the Coulomb matrix descriptor.

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BACKGROUND: Most long-term heavy drinkers do not have clinically evident chronic liver disease (CLD). However, at any time-point, their risk of developing CLD remains unknown. We aimed to evaluate the long-term outcomes of a group of heavy drinkers, without evidence of CLD at baseline. METHODS: A cohort of 123 long-term heavy drinkers without CLD were prospectively recruited in 2002 and retrospectively followed until 2018. RESULTS: At baseline (2002), median alcohol consumption was 271±203g/day during 21.5±20 years, 65% being abstinent during the previous 1.75±5 months. Patients were followed for 14±3 years. During follow-up, 53% reported any alcohol intake. Alcohol consumption during follow-up associated weakly with either 1- or 6-months previous abstinence at baseline. Until 2018, progression to CLD occurred in 6%, associating with years of alcohol intake during follow-up (OR 1.15 [1.01-1.31]) and baseline alkaline-phosphatase (OR 1.05 [1.01-1.10]). During follow-up, being abstinent for at least 1 year positively associated with CLD-free survival. 27% died (55% of cancer-mostly oropharyngeal cancer, 27% of cardiovascular disease, and 9% of liver disease), with a mean age of 71 years [69-74] (10 years less than the expected in the Portuguese population). Achieving abstinence for at least 1 year positively associated with overall survival, while smoking, and hepatic steatosis at baseline associated negatively. CONCLUSION: Long-term heavy drinkers seemed to have a decreased life expectancy compared with the overall Portuguese population. Cancer was the main cause of death. Our results suggest that progression to CLD depends mostly on continued alcohol intake. Alcohol abstinence, even if temporary, seems to decrease the risks of CLD and mortality.

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Understanding how adsorbates influence polaron behavior is of fundamental importance in describing the catalytic properties of TiO2. Carboxylic acids adsorb readily at TiO2 surfaces, yet their influence on polaronic states is unknown. Using UV photoemission spectroscopy (UPS), two-photon photoemission spectroscopy (2PPE), and density functional theory (DFT) we show that dissociative adsorption of formic and acetic acids has profound, yet different, effects on the surface density, crystal field, and photoexcitation of polarons in rutile TiO2(110). We also show that these variations are governed by the contrasting electrostatic properties of the acids, which impacts the extent of polaron-adsorbate coupling. The density of polarons in the surface region increases more in formate-terminated TiO2(110) relative to acetate. Consequently, increased coupling gives rise to new photoexcitation channels via states 3.83 eV above the Fermi level. The onset of this process is 3.45 eV, likely adding to the catalytic photoyield.

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Recently, high solar-to-hydrogen efficiencies were demonstrated using La and Rh co-doped SrTiO3 (La,Rh:SrTiO3) incorporated into a low-cost and scalable Z-scheme device, known as a photocatalyst sheet. However, the unique properties that enable La,Rh:SrTiO3 to support this impressive performance are not fully understood. Combining in situ spectroelectrochemical measurements with density functional theory and photoelectron spectroscopy produces a depletion model of Rh:SrTiO3 and La,Rh:SrTiO3 photocatalyst sheets. This reveals remarkable properties, such as deep flatband potentials (+2 V versus the reversible hydrogen electrode) and a Rh oxidation state dependent reorganization of the electronic structure, involving the loss of a vacant Rh 4d mid-gap state. This reorganization enables Rh:SrTiO3 to be reduced by co-doping without compromising the p-type character. In situ time-resolved spectroscopies show that the electronic structure reorganization induced by Rh reduction controls the electron lifetime in photocatalyst sheets. In Rh:SrTiO3, enhanced lifetimes can only be obtained at negative applied potentials, where the complete Z-scheme operates inefficiently. La co-doping fixes Rh in the 3+ state, which results in long-lived photogenerated electrons even at very positive potentials (+1 V versus the reversible hydrogen electrode), in which both components of the complete device operate effectively. This understanding of the role of co-dopants provides a new insight into the design principles for water-splitting devices based on bandgap-engineered metal oxides.

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Understanding the interaction of amino acids with metal surfaces is essential for the rational design of chiral modifiers able to confer enantioselectivity to metal catalysts. Here, we present an investigation of the adsorption of aspartic acid (Asp) on the Ni{100} surface, using a combination of synchrotron X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure, and density functional theory simulations. Based on the combined analysis of the experimental and simulated data, we can identify the dominant mode of adsorption as a pentadentate configuration with three O atoms at the bridge sites of the surfaces, and the remaining oxygen atom and the amino nitrogen are located on atop sites. From temperature-programmed XPS measurements, it was found that Asp starts decomposing above 400 K, which is significantly higher than typical decomposition temperatures of smaller organic molecules on Ni surfaces. Our results offer valuable insights into understanding the role of Asp as a chiral modifier of nickel catalyst surfaces in enantioselective hydrogenation reactions.