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Long‐chain organic halide salts are widely used in perovskite‐based optoelectronic devices for surface passivation owing to their capability to interact with the surface defects of perovskites. Here, aluminum oxide (AlOx) is introduced via atomic layer deposition onto octylammonium iodide (OAI) to exploit the benefits of organic halide salts without generating undesired defects. The devices incorporating AlOx on OAI‐treated perovskite (OAI/AlOx) show enhancement in both device performance and photo‐stability compared to those with only treatment. A diffusion of aluminum from AlOx into the perovskite through surface characterization contributes to a uniform photo‐generated carrier transport in both the surface and the bulk of the perovskite absorber. In addition, it is revealed that light‐induced two‐dimensional perovskite formation on OAI/AlOx. This may be ascribed to preventing the loss of OA cations due to the presence of AlOx, leading to a decrease in the number of iodine anions which suppresses the light‐induced degradation of corresponding devices. Consequently, the devices show over 24% efficiency and retain their efficiency over 1000 hours under continuous light illumination. [ABSTRACT FROM AUTHOR]

A novel series of zinc complexes, [EtZn(dab)]2 (1), [EtZn(damb)]2 (2), [EtZn(damp)]2 (3), and [EtZn(dadb)]2 (4), were prepared via single-step substitution. Further, these were analyzed by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), elemental analysis, single crystal X-ray diffraction analysis, and thermogravimetric analysis (TGA). The X-ray crystallography analysis revealed that all complexes exist as dimeric structures with distorted tetrahedral geometry having zinc centers that are interconnected via μ2-O bonding of the aminoalkoxy oxygen atom. TGA and thermal analysis of the complexes showed high volatilities and stabilities at sublimation temperatures of 70, 95, 90, and 105 °C at 0.5 Torr for the respective compounds. Precursor 3 was successfully used for ZnO thin film deposition by ALD. A growth rate per cycle (GPC) of 0.125 nm per cycle was obtained at 200 °C and XPS analysis confirmed the growth of highly pure ZnO films without carbon and nitrogen impurities, while XRD analysis revealed the deposition of reasonably crystalline films. Additionally, the high transmittance and wide bandgap of the films are suitable for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Ternary zinc tin oxide (ZTO) is one of the few environmental compatible buffer materials with the potential of replacing the n-CdS buffer in Cu(In,Ga)Se2 (CIGS) solar cells and other photovoltaic systems once its properties are fully understood and optimized. In this work, ZTO films were grown by atomic layer deposition and were logically characterized with the aim of understanding the correlations between compositional changes and film properties. The ZnO:SnO2 pulse ratio significantly affected the growth rate, crystal structure, morphology, and band gap of the ZTO films. By controlling the Sn/(Sn + Zn) atomic ratio, the optical band gap of the ZTO films was tuned between 3.05 and 3.36 eV. Integrating the ZTO films as buffer layers in CIGS solar cells, we observed that films with Sn concentrations of 9 to 16 at.% yielded photo-conversion efficiency close to 14%, which was very comparable to efficiency attained with the commonly used CdS buffer. Furthermore, using X-ray photoelectron spectroscopy analysis, we correlated the current-voltage behavior of the cells to the conduction band offset at the ZTO/CIGS interface. [ABSTRACT FROM AUTHOR]

High-quality lead sulfide (PbS) films are deposited on selected substrate chemistries by an H 2 S-free metal-organic chemical vapor deposition (MOCVD) process using a single-source metal-organic complex (Pb(dmampS) 2 ). The complex is synthesized via a salt metathesis reaction between PbCl 2  and lithium 1-(dimethylamino)-2-methylpropane-2-thiolate (Li(dmampS)) in diethyl ether. Subsequent film deposition is conducted by a simple thermolysis process in the absence of H 2 S, yet chemical and structural analysis confirm chemically stoichiometric and homogenous films. Mechanistic studies with electron impact mass spectroscopy (EIMS) and gas chromatography mass spectroscopy (GCMS) suggest the selective cleavage of C-S bonds in the complex as the reason for the facile PbS formation with negligible impurity incorporation. The high crystallinity, low hole concentrations, and charge transport properties comparable and in many cases superior to films produced by atomic layer deposition (ALD) testify to the quality of the films. Lastly, rigid and flexible photodetectors fabricated with the PbS films exhibit considerably high photocurrents, reliable switching characteristics, and high sensitivity over a broad spectral bandwidth, highlighting the potential for realizing practical broadband photodetectors., (© 2022 The Authors. Small published by Wiley-VCH GmbH.)

A new heteroleptic complex series of tin was synthesized by the salt metathesis reaction of SnX 2 (X = Cl, Br, and I) with aminoalkoxide and various N -alkoxy-functionalized carboxamide ligands. The complexes, [ClSn(dmamp)] 2 ( 1 ), [BrSn(dmamp)] 2 ( 2 ), and [ISn(dmamp)] 2 ( 3 ), were prepared from the salt metathesis reaction of SnX 2 with one equivalent of dmamp; [Sn(dmamp)(empa)] 2 ( 4 ), [Sn(dmamp)(mdpa)] 2 ( 5 ), and [Sn(dmamp)(edpa)] 2 ( 6 ) were prepared via the salt metathesis reaction using complex 2 with one equivalent of N -alkoxy-functionalized carboxamide ligand. Complexes 1 - 5 displayed dimeric molecular structures with tin metal centers interconnected by μ 2 -O bonding via the alkoxy oxygen atom. The molecular structures of complexes 1 - 5 showed distorted trigonal bipyramidal geometries with lone pair electrons in the equatorial position. Using complex 6 as a tin precursor, SnO x films were deposited by chemical solution deposition (CSD) and subsequent post-deposition annealing (PDA) at high temperatures. SnO and SnO 2 films were selectively obtained under controlled PDA atmospheres of argon and oxygen, respectively. The SnO films featured a tetragonal romarchite structure with high crystallinity and a preferred growth orientation along the (101) plane. They also exhibited a lower transmittance of >52% at 400 nm due to an optical band gap of 2.9 eV. In contrast, the SnO 2 films exhibited a tetragonal cassiterite crystal structure and an extremely high transmittance of >97% at 400 nm was observed with an optical band gap of 3.6 eV., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)