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Hybrid heterojunction solar cells (HHSCs) using crystalline Si nanowires (SiNWs) as the absorber and conducting polymer poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate) (PEDOTPSS) as the hole-selective transport layer (HTL) show great potential in both low-cost and high-power conversion efficiency (PCE). However, due to the poor wettability of the PEDOTPSS solution on SiNWs, conformal coverage of PEDOTPSS on SiNWs is not easy to achieve. Here, an effective method was developed to decrease the surface tension of the PEDOTPSS and increase the wettability between PEDOTPSS and SiNWs by incorporating organosilane into the PEDOTPSS solution. Two kinds of organosilanes including tetramethoxysilane (TMOS) and vinyltrimethoxysilane (VTMO) were selected as the additives. The surface passivation quality of the SiNWs was dramatically enhanced. The HHSCs utilizing VTMO as the additive show a higher open circuit voltage and higher PCE compared with the TMOS adding ones. By spin-coating Ag nanowires onto the PEDOTPSS HTL layer and using spin-coated phenyl-C61-butyric acid methyl ester as the electron-selective transport layer, a champion PCE up to 18.12% and a fill factor of 80.1% have been achieved on the full solution processed PEDOTPSS/n-type SiNWs HHSCs. The findings provide a simple and promising method to achieve high-performance PEDOTPSS/SiNWs HHSCs.An emerging class of methylammonium lead iodide (MAPbI3)-based Ruddlesden-Popper (RP) phase perovskites, BA2MAn-1PbnI3n+1 (n = 1-7), exhibit enhanced stability to environmental conditions relative to MAPbI3, yet still degrade at elevated temperatures. We experimentally determine the thermal conductivities of these layered RP phases for n = 1-6, where n defines the number of repeated perovskite octahedra per layer. We measure thermal conductivities of 0.37 ± 0.13/0.12, 0.17 ± 0.08/0.07, 0.21 ± 0.05/0.04, and 0.19 ± 0.04/0.03 W/m·K in thin films of n = 1-4 and 0.08 ± 0.06/0.04, 0.06 ± 0.04/0.03, 0.06 ± 0.03/0.03, and 0.08 ± 0.07/0.04 W/m·K in single crystals of n = 3-6. With the exception of n = 1, these thermal conductivities are lower than the range of 0.34-0.50 W/m·K reported for single-crystal MAPbI3. Reduced-order lattice dynamics modeling suggests that the initially decreasing trend of thermal conductivity in similarly oriented perovskites with increasing n may result from the transport properties of coherent phonons, emergent from the superstructure, that do not scatter at the interfaces of organic butylammonium chains and perovskite octahedra. Reduced group velocity of coherent phonons in n = 3-6, a consequence of band flattening in the phonon dispersion, is primarily responsible for their ultralow thermal conductivities. Similar effects on thermal conductivity have been experimentally demonstrated in deposited superlattices, but never in naturally defined materials such as RP phases. GIWAXS measurements reveal that higher n RP phase thin films are less orientationally controlled and therefore possess apparently elevated thermal conductivities relative to single crystals of the same n.The two paintings Infant Bacchanals (Museo Nazionale d'Arte Antica, Palazzo Barberini, Rome, Italy) executed by Nicolas Poussin (Les Andelys, 1594-Rome, 1665) in around 1626 are thought to have been painted "a guazzo", which means either with a glue or with an egg binding medium. To date, this has never been confirmed through analysis. Dual-beam time-of-flight secondary ion mass spectrometry (TOF-SIMS), using a bismuth cluster liquid metal ion gun and an argon gas cluster ion beam, allows the mapping of organic and inorganic matter on paintings cross sections, with the possibility to acquire submicrometer-resolution mass spectrometry images of the sample, together with high mass resolution using a delayed extraction of secondary ions. The surfaces of cross sections from both paintings were prepared beforehand either by polishing or by microtome cutting and then cleaned with the gas cluster ion beam directly inside the vacuum chamber of the instrument. The nature of the binders in the two paintings was investigated by TOF-SIMS analyses. By considering the uneven physical properties of the heterogeneous analyzed surfaces, several high-resolution images were recorded with different instrument settings. The detection of lipids seems to point toward an oil-containing medium, rather than a glue-binding medium. An emulsion made of oil and glue is another hypothesis to be explored to better understand the artist's working methods in his early career.The rich functionalities of transition-metal oxides and their interfaces bear an enormous technological potential. Its realization in practical devices requires, however, a significant improvement of yet relatively low electron mobility in oxide materials. Recently, a mobility boost of about 2 orders of magnitude has been demonstrated at the spinel-perovskite γ-Al2O3/SrTiO3 interface compared to the paradigm perovskite-perovskite LaAlO3/SrTiO3 interface. We explore the fundamental physics behind this phenomenon from direct measurements of the momentum-resolved electronic structure of this interface using resonant soft-X-ray angle-resolved photoemission. We find an anomaly in orbital ordering of the mobile electrons in γ-Al2O3/SrTiO3 which depopulates electron states in the top SrTiO3 layer. This rearrangement of the mobile electron system pushes the electron density away from the interface, which reduces its overlap with the interfacial defects and weakens the electron-phonon interaction, both effects contributing to the mobility boost. A crystal-field analysis shows that the band order alters owing to the symmetry breaking between the spinel γ-Al2O3 and perovskite SrTiO3. Band-order engineering, exploiting the fundamental symmetry properties, emerges as another route to boost the performance of oxide devices.Hydrogen adsorption on activated carbons (ACs) is a promising alternative to compression and liquefaction for storing hydrogen. Herein, we have studied hydrogen adsorption on six commercial ACs (CACs) with surface areas ranging from 996 to 2216 m2 g-1 in a temperature range of 77 to 273 K and pressures up to 15 MPa. Excess hydrogen adsorption capacities of 2.3 to 5.8 wt % were obtained at 77 K and 4 MPa. We demonstrated that, contrary to what is normally done, hydrogen capacity is more accurately predicted by the surface area determined by the nonlocal density functional theory method applied to N2 and CO2 adsorption data than by the Brunauer-Emmett-Teller (BET) area. The modified Dubinin-Astakhov (MDA) equation was used to fit the experimental adsorption data, and the relationship between the MDA parameters (nmax, Va, α, and β) and the textural properties of the CACs was determined for the first time. We concluded that the nmax and Va parameters are related to the BET area, while the α and β parameters are related to the average micropore size and total pore volume, respectively. α and β were used to evaluate the enthalpy and entropy of adsorption and we show that these parameters can be used to assess the best carbon for hydrogen storage or compression.Donor-acceptor (D-A) cyclopropanes have gained increased momentum over the past two decades. The use of these highly strained three-membered entities paved the way to innovative and original transformations yielding complex cyclic and acyclic architectures that otherwise might be difficult to address. Since the fundamentals were laid by Wenkert and Reissig in the late 1970s, the field has flourished impressively including asymmetric transformations as well as elegant synthetic applications in the construction of natural occurring products. In this Account, we aim to highlight especially our efforts in the context of an efficient access to sulfur- and selenium-containing compounds, of either cyclic or open-chain nature, by exploiting D-A cyclopropane chemistry. Light will be shed on the three fundamental transformations ring-opening reactions, cycloadditions, and rearrangements.Our synthetic endeavors started back in 2011 guided by quantum chemical studies to obtain 3,3'-linked bisthiophenes along with an unpr demonstrated the synthesis of benzo-fused dithiepines from in situ generated ortho-bisthioquinones, whereas the utilization of thia-Michael systems as a hetero-4π-component delivered tetrahydrothiepine derivatives containing just one sulfur atom embedded in the ring system.The ability to form freestanding oxide membranes of nanoscale thickness is of great interest for enabling material functionality and for integrating oxides in flexible electronic and photonic technologies. Recently, a route has been demonstrated for forming conducting heterostructure membranes of LaAlO3 and SrTiO3, the canonical system for oxide electronics. UNC1999 cost In this route, the epitaxial growth of LaAlO3 on SrTiO3 resulted in a strained state that relaxed by producing freestanding membranes with random sizes and locations. Here, we extend the method to enable self-formed LaAlO3/SrTiO3 micromembranes with control over membrane position, their lateral sizes from 2 to 20 μm, and with controlled transfer to other substrates of choice. This method opens up the possibility to study and use the two-dimensional electron gas in LaAlO3/SrTiO3 membranes for advanced device concepts.The membrane proteins of microbes are at the forefront of host and parasite interactions. Having a general view of the functions of microbial membrane proteins is vital for many biomedical studies on microbiota. Nevertheless, due to the strong hydrophobicity and low concentration of membrane proteins, it is hard to efficiently enrich and digest the proteins for mass spectrometry analysis. Herein, we design an enzymatic nanoreactor for the digestion of membrane proteins using methylated well-ordered hexagonal mesoporous silica (Met-SBA-15). The material can efficiently extract hydrophobic membrane proteins and host the proteolysis in nanopores. The performance of the enzymatic nanoreactor is first demonstrated using standard hydrophobic proteins and then validated using membrane proteins extracted from Escherichia coli (E. coli) or a mixed bacterial sample of eight strains. Using the nanoreactor, 431 membrane proteins are identified from E. coli, accounting for 38.5% of all membrane proteins of the species, which is much more than that by the widely used in-solution digestion protocol. From the mixed bacterial sample of eight strains, 1395 membrane proteins are identified using the nanoreactor. On the contrary, the traditional in-solution proteolysis workflow only leads to the identification of 477 membrane proteins, demonstrating that the Met-SBA-15 can be offered as an excellent tool for microbial membrane proteome research and is expected to be used in human microbiota studies, e.g. host-microbe interactions.Protein therapeutics have a major role in medicine in that they are used to treat diverse pathologies. Their three-dimensional structures not only offer higher specificity and lower toxicity than small organic compounds but also make them less stable, limiting their in vivo half-life. Protein analogues obtained by recombinant DNA technology or by chemical modification and/or the use of drug delivery vehicles has been adopted to improve or modulate the in vivo pharmacological activity of proteins. Nevertheless, strategies to improve the shelf-life of protein pharmaceuticals have been less explored, which has challenged the preservation of their activity. Herein, we present a methodology that simultaneously increases the stability of proteins and modulates the release profile, and implement it with human insulin as a proof of concept. Two novel thermally stable insulin composite crystal formulations intended for the therapeutic treatment of diabetes are reported. These composite crystals have been obtained by crystallizing insulin in agarose and fluorenylmethoxycarbonyl-dialanine (Fmoc-AA) hydrogels.