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Six materials were used as an interlayer at the anode side (anode interlayer [AIL]) of an archetypical planar heterojunction organic solar cell (OSC). In addition to two conventional wide bandgap hole transport materials (HTMs), tris(4‐carbazol‐9‐ylphenyl)amine (TCTA) and trans‐4,4′‐bis[N‐(naphthalen‐1‐yl)‐N‐phenylamino]stilbene (NPAE), we explore four narrow bandgap materials, bis(biphenylaminospiro)‐fumaronitrile (PhSPFN), bis(N‐(naphthalen‐1‐yl)‐N‐phenylamino)anthraquinone (NPAAnQ), bis‐(di(2‐fluorophenyl)aminospiro)‐fumaronitrile (FPhSPFN), and bis[4‐(N‐(pyren‐1‐yl)‐N‐phenylamino)phenyl]fumaronitrile (PyPAFN), the energy levels of which essentially align with the ones of SubPc, the active light‐absorbing material of the OSC study herein. By using a narrow bandgap AIL, universally enhanced short‐circuit current density and power conversion efficiencies (PCEs) have been achieved. In addition, one of these materials, FPhSPFN, results in a PCE of 5.13%, which is the highest reported value for SubPc solar cells with a similar architecture. This is ascribed to the formation of an otherwise passive exciton‐blocking interface. Furthermore, this demonstrates that charge selectivity by way of a high‐lying lowest unoccupied molecular orbital (LUMO) energy level is not a prerequisite for successful AIL design. As such, in terms of energy level alignment and bandgap energies, we establish a viable alternative approach toward interface and interlayer material design. [ABSTRACT FROM AUTHOR]

Abstract: This study reports design and synthesis of cone shaped hole transporting materials (HTM, i. e., H1 and H2). They are based on triphenylamine (TPA) and phenothiazine donors attached with two TPA moiety via electron rich π‐spacer (phenyl acrylonitrile). π‐spacers are proven to enhance the power conversion efficiency (PCE) of perovskite solar cells (PSCs) in the literature. Due to the electron withdrawing nature of the π‐spacer and the extended conjugation present in the HTMs proposed, a gradient for charge flow within the molecule is expected. This property is essential to transfer the electron from the HOMO of HTMs to the valence band of the perovskite via the arms of the HTMs. These HTMs do not show strong absorption in the visible region, exhibit high stokes shift and have their HOMO positioned above the perovskite's valence band. HTM layer of the PSCs were fabricated by a solution process method, at ambient conditions. A PCE of ∼1.9% at 1 sun condition was obtained, while under similar conditions the standard HTM (S‐OMeTAD) exhibited a PCE of 1.3%. [ABSTRACT FROM AUTHOR]

Abstract: The photovoltaic characteristics of CsBi3I10‐based solar cells with three dopant‐free hole‐conducting polymers are investigated. The effect on charge generation and charge recombination in the solar cells using the different polymers is studied and the results indicate that the choice of polymer strongly affects the device properties. Interestingly, for the solar cell with poly[[2,3‐bis(3‐octyloxyphenyl)‐5,8‐quinoxalinediyl]‐2,5‐thiophenediyl] (TQ1), the photon‐to‐current conversion spectrum is highly improved in the red wavelength region, suggesting that the polymer also contributes to the photocurrent generation in this case. This report provides a new direction for further optimization of Bi–halide solar cells by using dopant‐free hole‐transporting polymers and shows that the energy levels and the interaction between the Bi–halide and the conducting polymers are very important for solar cell performance. [ABSTRACT FROM AUTHOR]

Effective engineering of surface ligands in semiconductor nanocrystals can facilitate the electronic interaction between the individual nanocrystals, making them promising for low-cost optoelectronic applications. Here, the use of high purity Cu2ZnSnS4 (CZTS) nanocrystals as the photoactive layer and hole-transporting material is reported in low-temperature solution-processed solar cells. The high purity CZTS nanocrystals are prepared by engineering the surface ligands of CZTS nanocrystals, capped originally with the long-chain organic ligand oleylamine. After ligand removal, CZTS nanocrystals show substantial improvement in photoconductivity and mobility, displaying also an appreciable photoresponse in a simple heterojunction solar cell architecture. More notably, CZTS nanocrystals exhibit excellent hole-transporting properties as interface layer in perovskite solar cells, yielding power conversion efficiency (PCE) of 15.4% with excellent fill factor (FF) of 81%. These findings underscore the importance of removing undesired surface ligands in nanocrystalline optoelectronic devices, and demonstrate the great potential of CZTS nanocrystals as both active and passive material for the realization of low-cost efficient solar cells. [ABSTRACT FROM AUTHOR]

Summary Haematopoietic cell-specific transmembrane-4 (HTm4) is a four-transmembrane protein most closely related to CD20 and the beta subunit of the high affinity receptor for IgE (FcℇRIβ). To date, it has only been described in humans, where it is expressed in haematopoietic cells of both myeloid and lymphoid lineages. The function of HTm4 is unknown; however, as for CD20 and FcℇRI-β, it is likely to play a role in signal transduction as part of a multi-subunit cell surface receptor complex. In this study, we report the cDNA cloning and expression distribution of mouse HTm4. The deduced mouse HTm4 protein is of 213 amino acids, and contains four putative transmembrane domains. Mouse HTm4 shows 62% overall amino acid identity with human HTm4; the transmembrane regions are highly conserved between both species (75% identity), whereas the N- and C-terminal and inter-transmembrane loop regions are more divergent (52%). Interestingly, the N-terminal domain of mouse HTm4 is predicted to be 23 amino acids shorter, and the C-terminal domain 23 amino acids longer, than that of human HTm4. Northern blot and reverse transcriptase (RT)-PCR analysis suggest that mouse HTm4 mRNA is expressed at low levels only in spleen, bone marrow and peripheral blood leucocytes. This is the first report of the cloning of HTm4 from a species other than human, and provides important sequence information towards the understanding of the function of this poorly characterized four-transmembrane molecule. [ABSTRACT FROM AUTHOR]

Summary Haematopoietic cell-specific transmembrane-4 (HTm4) is a four-transmembrane protein most closely related to CD20 and the beta subunit of the high affinity receptor for IgE (FcℇRIβ). To date, it has only been described in humans, where it is expressed in haematopoietic cells of both myeloid and lymphoid lineages. The function of HTm4 is unknown; however, as for CD20 and FcℇRI-β, it is likely to play a role in signal transduction as part of a multi-subunit cell surface receptor complex. In this study, we report the cDNA cloning and expression distribution of mouse HTm4. The deduced mouse HTm4 protein is of 213 amino acids, and contains four putative transmembrane domains. Mouse HTm4 shows 62% overall amino acid identity with human HTm4; the transmembrane regions are highly conserved between both species (75% identity), whereas the N- and C-terminal and inter-transmembrane loop regions are more divergent (52%). Interestingly, the N-terminal domain of mouse HTm4 is predicted to be 23 amino acids shorter, and the C-terminal domain 23 amino acids longer, than that of human HTm4. Northern blot and reverse transcriptase (RT)-PCR analysis suggest that mouse HTm4 mRNA is expressed at low levels only in spleen, bone marrow and peripheral blood leucocytes. This is the first report of the cloning of HTm4 from a species other than human, and provides important sequence information towards the understanding of the function of this poorly characterized four-transmembrane molecule. [ABSTRACT FROM AUTHOR]

Summary: We introduce the first concurrent data structure algorithm designed for speculative executions. Prior to this work, concurrent structures were mainly designed for their pessimistic (non‐speculative) accesses to have a predictable asymptotic complexity. Researchers tried to evaluate transactional memory using such structures whose prominent example is the red‐black tree library developed by Oracle Labs that is part of multiple benchmark distributions. Although well‐engineered, such structures remain badly suited for speculative accesses, whose step complexity might raise dramatically with contention. We propose a binary search tree data structure whose key novelty stems from the decoupling of update operations, ie, instead of performing an update operation in a single large transaction, it is split into one transaction that modifies the abstraction state and several other transactions that restructure the tree implementation in the background. This results in a speculation‐friendly tree (s‐tree) that outperforms previous HTM‐based and STM‐based trees by being transiently unbalanced during contention peaks and by rebalancing in quadratic time when contention disappears. In particular, the s‐tree is shown correct, reusable, and speeds up a transaction‐based travel reservation application by up to 3.5×. [ABSTRACT FROM AUTHOR]