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The ability to precisely edit genomes by deleting or adding genetic information enables the study of biological functions and the building of efficient cell factories. In many unconventional yeasts, such as those promising new hosts for cell factory design but also human pathogenic yeasts and food spoilers, this progress has been limited by the fact that most yeasts favour non‐homologous end joining (NHEJ) over homologous recombination (HR) as a DNA repair mechanism, impairing genetic access to these hosts. In mammalian cells, small molecules that either inhibit proteins involved in NHEJ, enhance protein function in HR, or arrest the cell cycle in HR‐dominant phases are regarded as promising agents for the simple and transient increase of HR‐mediated genome editing without the need for a priori host engineering. Only a few of these chemicals have been applied to the engineering of yeast, although the targeted proteins are mostly conserved, making chemical agents a yet‐underexplored area for enhancing yeast engineering. Here, we consolidate knowledge of the available small molecules that have been used to improve HR efficiency in mammalian cells and the few ones that have been used in yeast. We include available high‐throughput‐compatible NHEJ/HR quantification assays that could be used to screen for and isolate yeast‐specific inhibitors. [ABSTRACT FROM AUTHOR]

Background Information: Arpin, an Arp2/3 inhibitory protein, inhibits lamellipodial protrusions and cell migration. Arpin expression is lost in tumor cells of several cancer types., Results: Here we analyzed expression levels of Arpin and various markers using Reverse Phase Protein Array (RPPA) in human mammary carcinomas. We found that Arpin protein levels were correlated with those of several DNA damage response markers. Arpin-null cells display enhanced clustering of double stand breaks (DSBs) when cells are treated with a DNA damaging agent, in line with a previously described role of the Arp2/3 complex in promoting DSB clustering for homologous DNA repair (HDR) in the nucleus. Using a specific HDR assay, we further showed that Arpin depletion increased HDR efficiency two-fold through its ability to inactivate the Arp2/3 complex., Conclusions: Arpin regulates both cell migration in the cytosol and HDR in the nucleus., Significance: Loss of Arpin expression coordinates enhanced cell migration with up-regulated DNA repair, which is required when DNA damage is induced by active cell migration., (© 2024 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.)

The combination of III–V compound semiconductor materials and organic semiconductor materials to construct hybrid solar cells is a potential pathway to resolve the problems of conventional doped p–n junction solar cells, such as complexities in fabrication process and high costs. This review presents the recent progress of organic–inorganic hybrid solar cells based on polymers and III–V semiconductors, from materials to devices. The available growth process for planar/nanostructured III–V semiconductor materials, along with patterning and etching processes for nanostructured materials, are reviewed. As an emphasis of this review, advanced device structure designs are reviewed for facilitation of carrier collection and high efficiency, at planar structure level and nanowire structure level, respectively. Optimization pathways for efficiency enhancement are discussed with respect to polymer layers and surface/interface passivation, respectively. Finally, perspectives on the future development of such hybrid cells are presented. [ABSTRACT FROM AUTHOR]

Ultrathin (UT) crystalline Si wafers, which are more flexible than conventional ones, can apply to curved surfaces, enabling a wide range of applications such as building‐integrated photovoltaics, vehicle‐integrated photovoltaics, and wearable devices. Thinner wafers require more effective light trapping; thus, surface texturing in microscale is a common approach to compensate for the reduced thickness by enhancing the light pathlength. Microscale textures, however, deteriorate the mechanical flexibility due to stress concentration in the valley of the microtextures. In this study, a laser‐assisted nanotexturing process is proposed for enhanced flexibility of the UT Si solar cells with a 50 μm thickness while maintaining light‐trapping performances. A nanolens array is used to focus laser onto the Si wafers, inducing the formation of nanoparticle etch masks for nanopyramid texturing in an alkaline solution. The origin of the enhanced flexibility of the nanotextured Si wafers is discussed by a micromechanics simulation study. Herein, nanotexturing technique is applied to UT Si‐based passivated emitter rear cells and the enhanced flexibility of the cells with a 26 mm critical bending radius is demonstrated. Also, it is shown that the nanotextured Si wafer provides a higher efficiency of 18.68%, whereas the microtextured one exhibits 18.10%. [ABSTRACT FROM AUTHOR]

Narrow bandgap quantum dots (QDs) are an important class of materials for near‐infrared (NIR) optoelectronic devices owing to their size‐tunable bandgap and chemical root processing. In photovoltaic applications, NIR QDs could be particularly useful to complement the sub‐bandgap transmission loss of NIR solar radiation from perovskite and c‐Si solar cells. However, insufficient carrier extraction thickness associated with the narrow NIR excitonic bandwidth of QDs limits the conversion efficacy of the broad NIR solar spectrum. Here, we utilize a multi‐bandgap QD ensemble which widens the NIR absorption bandwidth to mimic the broad solar spectrum. A solution‐phase ligand passivation strategy is used to control doping properties and energy level alignment of multi‐bandgap QDs. We successfully developed bulk‐heterojunction solar cells using the multi‐bandgap QD ensemble, which yields higher carrier extraction thickness and broader NIR absorption. The gain from NIR absorption and carrier transport resulted in higher short‐circuit current generation and power conversion efficiency (PCE) in solar cell devices. The champion device shows 8.73% PCE under 1.5 AM solar illumination and 7.44% and 5.05% PCE for the NIR photons transmitted from perovskite and c‐Si layers. [ABSTRACT FROM AUTHOR]

Glass is the most widely used transparent material for photovoltaic (PV) panels. Unfortunately, the glass introduces an additional interface and therefore optical losses, which can be mitigated using antireflection (AR) coatings. This article reports a scalable method to prepare AR coatings from ZnO nanowires (NWs) sorted by their size. The measured AR performance depends on the coating coverage and ZnO NW size, which is explained by scattering and absorption cross section simulations. Randomly oriented and size fractioned ZnO NWs with an average diameter of 19–30 nm and lengths of 121–273 nm demonstrate increased transmittance and decreased reflectance compared to a glass substrate in case of low coverage. The experimental PV modules with ZnO NW coatings show an 1.2% increase of the short circuit current. A strategy to decouple ZnO NW synthesis from AR coating preparation allows to tune NW reflectance and other optical properties by varying the length, diameter, and orientation of the constituent NWs. The proposed AR coating made from size‐sorted nanomaterials is not limited to ZnO and the method could be adapted to other materials and nanostructures. [ABSTRACT FROM AUTHOR]

JMJD2A is a histone lysine demethylase which recognizes and demethylates H3K9me3 and H3K36me3 residues and is overexpressed in various cancers. It utilizes a tandem tudor domain to facilitate its own recruitment to histone sites, recognizing various di‐ and tri‐methyl lysine residues with moderate affinity. In this study, we successfully engineered the tudor domain of JMJD2A to specifically bind to H4K20me3 with a 20‐fold increase of affinity and improved selectivity. To reveal the molecular basis, we performed molecular dynamics and free energy decomposition analysis on the human JMJD2A tandem tudor domains bound to H4K20me2, H4K20me3, and H3K23me3 peptides to uncover the residues and conformational changes important for the enhanced binding affinity and selectivity toward H4K20me2/3. These analyses revealed new insights into understanding chromatin reader domains recognizing histone modifications and improving binding affinity and selectivity of these domains. Furthermore, we showed that the tight binding of JMJD2A to H4K20me2/3 is not sufficient to improve the efficiency of CRISPR‐CAS9 mediated homology directed repair (HDR), suggesting a complicated relationship between JMJD2A and the DNA damage response beyond binding affinity toward the H4K20me2/3 mark. [ABSTRACT FROM AUTHOR]

Remarkable progress over the past decade in photovoltaics using solution‐processed nanomaterials as light absorbers has placed colloidal quantum dot (CQD)‐based devices on the map. As such, AgBiS2 CQDs have garnered significant attention as materials exhibiting a high absorptivity with environmentally benign alternatives to Pb‐chalcogenide or Pb halide perovskite‐CQDs. Yet, AgBiS2 CQD‐based solar cells have gravely underperformed compared to Pb‐containing devices, particularly in the metrics of charge carrier extraction from the AgBiS2 absorber, hence its relative mediocrity. To specifically address the extraction efficiency, a bulk heterostructure (QPB) interlayer at the CQD/polymer interface in AgBiS2 CQD solar cells, resulting in an increase of the power conversion efficiency (PCE), e.g., from 5.10% (an average PCE of 4.94 ± 0.11%) to 6.78% (an average PCE of 6.59 ± 0.11%) is deviced. The improved charge extraction at the hole‐collecting interface is responsible for the superior performance, corroborated by high photocurrent (21.5 mA cm–2) and fill factor (67%). The QPB‐interlayered solar cell also gives rise to outstanding durability of the devices, retaining above 95% of the original PCE for 5 months in ambient air. Our strategy based on an eco‐friendly CQD/polymer could provide an effective route for next‐generation optoelectronics with enhanced charge collection and durability. [ABSTRACT FROM AUTHOR]

A combination of AlGaInP/AlGaAs/GaAs is commonly used in world‐record five‐ and six‐junction solar cells for their easily tunable bandgap and nearly matched lattice constants. Wide‐range low reflectivity is of significant importance in this three‐junction solar cell (3JSC), but also difficult to achieve particularly in 300–400 nm due to the optical properties of III–V alloys. Therefore, quadruple‐layer antireflection coatings (QLAR) composed of ZnS and MgF2 films are studied in this article for both performance and practicability. Optical constants of ZnS and MgF2 films are extracted by variable angle spectroscopic ellipsometry. 150 °C is determined as the best deposition temperature to decrease parasitic absorption in ZnS films. The antireflection coating is designed by the transfer‐matrix method considering both low reflectivity in a wide range of 300–900 nm and balanced subcell current density. Fabricated 3JSC with optimized MgF2/ZnS/MgF2/ZnS QLAR is demonstrated to possess low reflection losses in a broadband spectral range, with an average of only 1.59% in 300–900 nm. This boosts the integral current density to 11.58, 11.35, and 11.25 mA cm−2 for AlGaInP, AlGaAs, and GaAs subcells, respectively. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of single‐junction perovskite solar cells (PSCs) is being rapidly promoted towards their theoretical limit, with a certified value of 25.7%. Reducing optical loss will further contribute to PCE improvement. Here, the optical loss including reflection loss, absorption loss, and transmission loss in printable mesoscopic perovskite solar cells (p‐MPSCs) is analyzed. A printable mesoporous SiO2 antireflection coating for improving the transmittance of the fluorine‐doped tin oxide (FTO) glass substrate by reducing optical reflection at the air/glass interface is reported. With modulated porosity and thickness, the mesoporous SiO2 film constructs a graded refractive index interface and increases the transmittance of FTO glass by ≈2%–4% in the spectral range of 350–800 nm at normal incident angle with the highest transmittance improved from 85% to 89%. The SiO2 coating also exhibits wide‐angle and broadband antireflection properties. The coatings successfully help p‐MPSCs obtain about an average 3% enhancement in the short‐circuit current density (JSC) and PCE. This study demonstrates the necessity of optical management for efficient solar cells and provides a cost‐effective and scalable antireflection coating for the future realistic application of PSCs. [ABSTRACT FROM AUTHOR]

Progress in device engineering and surface passivation strategies has led to steady progress in colloidal quantum dot (QD) solar cells. Bulk homojunction (BHJ) device architecture has several advantages over the conventional planar junction in developing QD solar cells. Herein, surface ligand chemistry is utilized to control the doping type and dispersibility of oppositely doped PbS QDs to develop BHJ solar cells. Thiocyanate and thiol ligand combination is introduced to develop p‐PbS QD ink, which is blended with halide‐passivated n‐PbS QDs to build BHJ solar cells. It is shown that BHJ solar cells are benefited from high energy offset and higher hole mobility. This leads to the superior carrier extraction from a thicker active layer without compromising fill factor and open circuit voltage. Power conversion efficiency has reached 10.7% in 530 nm‐thick BHJ solar cells, a 24% improvement over the best performing planar solar cells. With the help of the 1D solar cell capacitance simulator, it is shown that a 15% efficient QD solar cell can be realized by further improving the hole mobility above 0.1 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

Colloidal semiconductor quantum dots (QDs) can be considered a promising material platform for solution‐processed laser diodes. However, due to some fundamental challenges, the realization of electrically pumped lasing based on QDs remains unresolved. Here, a binary blend of QDs and ZnO nanocrystals is employed, which serve as nano‐sized scatterers to facilitate waveguide gain in ultra‐thin films. By carefully engineering the electric field in these films, an infrared amplified spontaneous emission in a record thin colloidal gain medium is observed, with a thickness of 16 nm, at a wavelength of 1675 nm. Employing these binary blends as a gain medium, an optically pumped infrared stimulated emission in a full‐stacked light‐emitting diode (LED) device is demonstrated. The functional LED device, which comprises a single layer of graphene as an anode electrode, shows strong electroluminescence under electrical injection. This study suggests a promising device for realizing infrared QD‐based laser diodes. [ABSTRACT FROM AUTHOR]

Me3Si−X (X=CN, N3, OCN, and SCN) was treated with the Lewis acids GaCl3 and B(C6F5)3 in toluene yielding the desired adducts Me3Si−X→GaCl3 and Me3Si−X→B(C6F5)3. All synthesized adducts were isolated and completely characterized including single crystal structure elucidations. The different structures, thermodynamics of formation and charge transfer effects are discussed on the basis of experimental and theoretical data. [ABSTRACT FROM AUTHOR]

Light management holds great promise of realizing high-performance perovskite solar cells by improving the sunlight absorption with lower recombination current and thus higher power conversion efficiency (PCE). Here, a convenient and scalable light trapping scheme is demonstrated by incorporating bioinspired moth-eye nanostructures into the metal back electrode via soft imprinting technique to enhance the light harvesting in organic-inorganic lead halide perovskite solar cells. Compared to the flat reference cell with a methylammonium lead halide perovskite (CH3NH3PbI3− xCl x) absorber, 14.3% of short-circuit current improvement is achieved for the patterned devices with moth-eye nanostructures, yielding an increased PCE up to 16.31% without sacrificing the open-circuit voltage and fill factor. The experimental and theoretical characterizations verify that the cell performance enhancement is mainly ascribed by the broadband polarization-insensitive light scattering and surface plasmonic effects due to the patterned metal back electrode. It is noteworthy that this light trapping strategy is fully compatible with solution-processed perovskite solar cells and opens up many opportunities toward the future photovoltaic applications. [ABSTRACT FROM AUTHOR]

In this work, a new equation consist of A⋅⋅⋅B, B⋅⋅⋅C, A⋅⋅⋅BC, and AB⋅⋅⋅C interactions is proposed for calculating the total interaction energy of noncyclic ABC triads. New equations are also proposed for calculating the changes in values of A⋅⋅⋅B and B⋅⋅⋅C interactions on the formation of triad from the corresponding dyads. The advantages of equations proposed here in comparison with many-body interaction energy approach are discussed. All proposed equations were tested in F3MLi⋅⋅⋅NCH⋅⋅⋅HLH and F3MLi⋅⋅⋅HLH⋅⋅⋅HCN (M = C, Si; L = Be, Mg) as well as H3N⋅⋅⋅XY⋅⋅⋅HF (X, Y = F, Cl, Br) noncyclic A⋅⋅⋅B⋅⋅⋅C triads. The data show that the total cooperativity of triad correlates well with the sum of the changes in values of A⋅⋅⋅B and B⋅⋅⋅C interactions calculated through new equations proposed here. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The effect of several Lewis acids on the CBS catalyst (named after Corey, Bakshi and Shibata) was investigated in this study. While 2H NMR spectroscopic measurements served as gauge for the activation capability of the Lewis acids, in situ FT-IR spectroscopy was employed to assess the catalytic activity of the Lewis acid oxazaborolidine complexes. A correlation was found between the Δ δ(2H) values and rate constants kDA, which indicates a direct translation of Lewis acidity into reactivity of the Lewis acid-CBS complexes. Unexpectedly, a significant deviation was found for SnCl4 as Lewis acid. The SnCl4-CBS adduct was much more reactive than the Δ δ(2H) values predicted and gave similar reaction rates to those observed for the prominent AlBr3-CBS adduct. To rationalize these results, quantum mechanical calculations were performed. The frontier molecular orbital approach was applied and a good correlation between the LUMO energies of the Lewis acid-CBS-naphthoquinone adducts and kDA could be found. For the SnCl4-CBS-naphthoquinone adduct an unusual distortion was observed leading to an enhanced Lewis acidity. Energy decomposition analysis with natural orbitals for chemical valence (EDA-NOCV) calculations revealed the relevant interactions and activation mode of SnCl4 as Lewis acid in Diels-Alder reactions. [ABSTRACT FROM AUTHOR]

Films with a fine structure consisting of innumerable nanopillars of mesoporous silica (MPS) are formed by a reactive ion etching process with a fluorine-containing gas. Each nanopillar has a tapered shape with a uniform height, which effectively suppresses reflection by the formation of an ideal graded refractive index structure. The nanopillars are spontaneously formed under low-pressure conditions, wherein locally deposited Al−F compounds, originating from an alumina plate in the etching chamber, work as a fine etching mask. The high etching rate of the MPS film allows a very high aspect ratio of the nanopillars. The refractive index of the MPS nanopillars can be universally tuned by a controlled incorporation of TiO2 into the mesopores, which results in effective reduction of reflectance on a given substrate. The outstanding antireflection performance is experimentally demonstrated for glass substrates with a wide refractive index range. [ABSTRACT FROM AUTHOR]

Quantum chemical calculations of reaction mechanisms for the formal [2+2] addition of ethylene and acetylene to the amido-substituted digermyne and distannyne Ph2NEENPh2 (E=Ge, Sn) have been carried out by using density functional theory at the BP86/def2-TZVPP level. The nature and bonding situations were studied with the NBO method and with the charge and energy decomposition analysis EDA-NOCV. The addition of ethylene to Ph2NEENPh2 takes place through an initial [2+1] addition to one metal atom and consecutive rearrangement to four-membered cyclic species, which feature a weak EE bond. Rotation about the CC bond with concomitant rupture of the EE bond leads to the 1,2-disubstituted ethanes, which have terminal E(NPh2) groups. The overall reaction Ph2NEENPh2+C2H4→(Ph2N)EC2H4E(NPh2) has very low activation barriers and is slightly exergonic for E=Ge but slightly endergonic for E=Sn. The analysis of the electronic structure shows that there is charge donation of nearly one electron to the ethylene moiety already in the first part of the reaction. The energy partitioning analysis suggests that the HOMO(Ph2NEENPh2)→LUMO(C2H4) interaction has a similar strength as the HOMO(C2H4)→LUMO(Ph2NEENPh2) interaction. The [2+2] addition of acetylene to Ph2NEENPh2 also takes place through an initial [2+1] approach, which eventually leads to 1,2-disubstituted olefins (Ph2N)EC2H2E(NPh2). The formation of the energetically lowest lying conformations of cis-(Ph2N)EC2H2E(NPh2), which occurs with very low activation barriers, is clearly exergonic for the germanium and the tin compound. The trans-coordinated isomers of (Ph2N)EC2H2E(NPh2) are slightly lower in energy than the cis form but they are separated by a substantial energy barrier for the rotation about the CC bond. The energy decomposition analysis indicates that the initial reaction takes place under formation of electron-sharing bonds between triplet fragments rather than HOMO-LUMO interactions. [ABSTRACT FROM AUTHOR]

Reactivity of [{2,6-(Me2NCH2)2C6H3}Sn]2 ( 1) towards functionalized diorganodisulfides R2S2 as oxidizing agents was studied. The reactions provided organotin(II) thio derivatives {2,6-(Me2NCH2)2C6H3}Sn(S2CNMe2) ( 2), {2,6-(Me2NCH2)2C6H3}Sn (SC6H4-2-NH2) ( 3) and {2,6-(Me2NCH2)2C6H3}Sn(SC5H4N) ( 4). The 119Sn NMR spectroscopic data of 2- 4 suggest different electronic saturation of the tin(II) atoms in 2- 4, which caused redox stability of 2 and easy oxidation of 3 and 4. The treatment of the latter compounds with diorgano disulfides R2S2 yielded organotin(IV) thio derivatives {2,6-(Me2NCH2)2C6H3}Sn(SC6H4-2-NH2)3 ( 5) and {2,6-(Me2NCH2)2C6H3}Sn(SC5H4N)3 ( 6). In addition, oxidation of 3 and 4 with the radical TEMPO (2,2,6,6-tetramethylpiperidin-1-oxyl) provided organotin(IV) hydroxide [{2,6-(Me2NCH2)2C6H3}Sn(SC6H4-2-NH)(μ-OH)]2 ( 7) and organotin(IV) oxide [{2,6-(Me2NCH2)2C6H3}Sn(SC5H4N)(μ-O)]3 ( 8). All prepared compounds 2- 8 were characterized by using multinuclear NMR spectroscopy, and the molecular structures of 2, 4, 7 and 8 were determined by using X-ray diffraction. Compounds 2- 4 were also characterized by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

We demonstrate a textured surface antireflection layer containing ZnO nanorod arrays (ZNAs) for light harvesting in a broad wavelength range by a nondestructive and direct procedure based on atomic-layer deposition and solution growth. The size and morphology of nanorod arrays can be designed according to the textured morphology. The requirements of ZNAs for mc-Si and c-Si cells are discussed in detail by controlling their growth conditions, while atomic-layer deposition is also used for accurate adjustment. By the decoration of nanorod arrays, the weighted average reflectance Rw decreased by more than 56%, resulting in an enhancement of external quantum efficiency and an improvement of about 3.64% for short-circuit current density. The antireflection method will open up alternative opportunities for achieving feasible, compatible, and nondestructive nonreflecting layers towards optimal light harvesting for PV cells. [ABSTRACT FROM AUTHOR]

Quantum chemical calculations using DFT and ab initio methods were carried out on the structures of the title compounds. The nature of the bonding was investigated with an energy decomposition analysis. The calculations predict that the planar C2 v allyl structures of the neutral and charged heavier group-14 homologues [H2 E- E(H)- EH2]-, ·,+ ( E = Si - Sn) are no minima on the potential energy surface. Energy minima for allyl-type structures of the latter systems possess Cs symmetry and pyramidal EH2 groups. The energetically lowest lying form of [H2 E- E(H)- EH2]-, ·,+ ( E = Si - Sn) has a cyclic structure for the neutral molecules and the anion and a quasi-cyclic equilibrium arrangement for the cations. In contrast, the cyclic isomers of the carbon molecules [H2C-C(H)-CH2]-, ·,+ are significantly higher in energy than the allyl structures. Energy decomposition analyses show that the lower stability of the planar C2 v allyl structures of [H2 E- E(H)- EH2]-, ·,+ ( E = Si - Sn) does not come from weak π conjugation. The relative contribution of π conjugation in the latter species is even higher than in the allyl system of carbon. The cyclic form of [H2 E- E(H)- EH2]-, ·,+ ( E = Si - Sn) is lower in energy than the allyl form, because the σ bonding in the former structures is much stronger than in the latter. This overcompensates the higher Pauli repulsion in the cyclic form. In the carbon systems, the Pauli repulsion of the cyclic structures is very strong, because the bonds are much shorter than in the heavier homologues. Consequently, the stronger Pauli repulsion in the cyclic isomers is not compensated by the stronger attraction compared with the allyl system. [ABSTRACT FROM AUTHOR]

Novel ZnO nanocone anti-reflective coating (ARC) was realized on ITO-Si metal-insulator-semiconductor (MIS) photodetector. The ZnO nanocone-coated device demonstrated significant suppression of reflectance compared with that of a conventional planar device. The ZnO nanocone MIS photodetector showed a 15% enhanced external quantum efficiency (EQE) compared to a planar MIS photodetector, and indicated a flat response over a broad range of wavelength from the visible to IR spectra. In addition, the EQE of the nanocone device exhibited a stable response with respect to the angle of incidence, which indicates improved device characteristics of the ZnO nanocone ARC. [ABSTRACT FROM AUTHOR]

This article reviews recent developments in nanowire‐based photovoltaics (PV) with an emphasis on III–V semiconductors including growth mechanisms, device fabrication and performance results. We first review the available nanowire growth methods followed by control of nanowire growth direction and crystal structure. Important device issues are reviewed, including optical absorption, carrier collection, strain accommodation, design for high efficiency, tunnel junctions, Ohmic contact formation, passivation and doping. Performance data of III–V nanowire cells and the primary challenges in nanowire PV are summarized. Many of the issues discussed here are also applicable to other nanowire devices such as photodetectors. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) Part of Focus Issue on “Semiconductor Nanowires” (Eds.: Chennupati Jagadish, Lutz Geelhaar, Silvija Gradecak) To overcome the limitations of current III–V multi‐junction solar photovoltaic (PV) cells, III–V nanowire‐based PV is being aggressively pursued by numerous groups. This article provides a comprehensive review of nanowire‐based PV covering all aspects of design for high power conversion efficiency including nanowire growth methods, growth direction, crystal structure, optical absorption, carrier collection, strain accommodation, tunnel junctions, Ohmic contact formation, passivation and doping. [ABSTRACT FROM AUTHOR]

In the fabrication of III-V semiconductor nanostructures for electronic and optoelectronic devices, techniques that are capable of removing material with monolayer precision are as important as material growth to achieve best device performances. A robust chemical treatment is demonstrated using sulfur (S)-oleylamine (OA) solution, which etches layer by layer in an inverse epitaxial fashion and simultaneously passivates the surface. The application of this process to push the limits of top-down nanofabrication is demonstrated by the realization of InP-based high optical quality nanowire arrays, with aspect ratios more than 50, and nanostructures with new topologies. The findings are relevant for other III-V semiconductors and have potential applications in III-V device technologies. [ABSTRACT FROM AUTHOR]

Aromatische niedervalente Blei ‐ Analoga eines Indenylanions (siehe Schema; 1) werden durch SnCl2 unter Bildung des basestabilisierten Blei(I) ‐ Dimers 2 oxidiert. Die Reduktion von 2 mit Lithium führt wieder zu 1. Beide Spezies wurden NMR ‐ spektroskopisch und Röntgen ‐ kristallographisch charakterisiert. [ABSTRACT FROM AUTHOR]

In this work, both planar and textured, industrial scale (156 mm × 156 mm) single-crystalline silicon ( Si) solar cells have been fabricated using zinc oxide ( ZnO) nanorods as antireflection coating ( ARC). ZnO nanorods were grown in a few minutes via hydrothermal method within a commercially available microwave oven. Relative improvement in excess of 65% in the reflectivity was observed for both planar and textured Si surfaces. Through ZnO nanorods, effective lifetime (τeff) measurements were presented to investigate the surface passivation property of such an ARC layer. ZnO nanorods increased the τeff from 9 to 71 μs at a carrier injection level of 1015 cm−3. Increased carrier lifetime revealed the passivation effect of the ZnO nanorods in addition to their ARC property. 33% and 16% enhancement in the photovoltaic conversion efficiency was obtained in planar and textured single-crystalline solar cells, respectively. Our results reveal the potential of ZnO nanorods as ARC that can be deposited through simple solution-based methods and the method investigated herein can be simply adapted to industrial scale fabrication. [ABSTRACT FROM AUTHOR]

An optimized four-layer tailored- and low-refractive index anti-reflection (AR) coating on an inverted metamorphic (IMM) triple-junction solar cell device is demonstrated. Due to an excellent refractive index matching with the ambient air by using tailored- and low-refractive index nanoporous SiO2 layers and owing to a multiple-discrete-layer design of the AR coating optimized by a genetic algorithm, such a four-layer AR coating shows excellent broadband and omnidirectional AR characteristics and significantly enhances the omnidirectional photovoltaic performance of IMM solar cell devices. Comparing the photovoltaic performance of an IMM solar cell device with the four-layer AR coating and an IMM solar cell with the conventional SiO2/TiO2 double layer AR coating, the four-layer AR coating achieves an angle-of-incidence (AOI) averaged short-circuit current density, JSC, enhancement of 34.4%, whereas the conventional double layer AR coating only achieves an AOI-averaged JSC enhancement of 25.3%. The measured reflectance reduction and omnidirectional photovoltaic performance enhancement of the four-layer AR coating are to our knowledge, the largest ever reported in the literature of solar cell devices. [ABSTRACT FROM AUTHOR]

A modified form of detailed balance theory is applied to a tandem semiconductor solar cell formed from a vertical nanowire array on a planar substrate. The concept of an effective packing fraction is introduced to account for the light trapping properties of the nanowire array. Our model provides important design criteria for the nanowire-planar system, including the requirement for optimum performance of a lower energy nanowire bandgap than in an ideal all-planar tandem cell. Using realistic design parameters for a III-V nanowire-silicon bottom cell system we predict an efficiency enhancement of 22-27% relative to a planar silicon cell. [ABSTRACT FROM AUTHOR]