Soft lattice and strong exciton–phonon coupling have been demonstrated in layered double perovskites (LDPs) recently; therefore, LDPs represents a promising class of compounds as excellent self‐trapped exciton (STE) emitters for applications in solid‐state lighting. However, few LDPs with outstanding STE emissions have been discovered, and their optoelectronic properties are still unclear. Based on the three‐dimensional (3D) Cs2NaInCl6, we synthesized two 2D derivatives (PEA)4NaInCl8:Sb (PEA=phenethylamine) and (PEA)2CsNaInCl7:Sb with monolayer and bilayer inorganic sheets by a combination of dimensional reduction and Sb‐doping. Bright broadband emissions were obtained for the first time under ambient temperature and pressure, with photoluminescence quantum efficiency (PLQE) of 48.7 % (monolayer) and 29.3 % (bilayer), superior to current known LDPs. Spectroscopic characterizations and first‐principles calculations of excited state indicate the broadband emissions originate from STEs trapped at the introduced [SbCl6]3− octahedron.

Indium (In)-based halide perovskites are desirable for next-generation phosphors and emitting devices, due to their broad emission, nontoxicity, and oxidization avoidance capabilities. However, the In-based perovskites always exhibit low external photoluminescence quantum efficiency (PLQE) as a result of their weak light absorption near the corresponding excitation region, and thus, are limited in extended applications. Herein, we have developed an antimony (Sb)-doping strategy to improve the absorption ability of Cs 2 InCl 5 •H 2 O in the ultraviolet region. Excitingly, we obtained a warm-light phosphor with ultrahigh external (internal) PLQE of 72.8% (86.7%). Typically, upon 1.5% Sb doping, the single-crystalline Cs 2 InCl 5 •H 2 O perovskite displayed a stronger warm-light emission at ∼ 610 nm with a large Stokes shift of 295 nm and full width at half maximum (FWHM) of 164 nm. Density functional theory (DFT) calculations revealed that the Sb-doping induced an impurity level in the bandgap, increasing the density of state (DOS), and promoted more carriers into the conduction band maximum. Furthermore, external PLQE from 18% to 59% could be realized in other zero-dimensional In-based perovskites through the same doping strategy.

Double halide perovskites are a class of promising semiconductors applied in photocatalysis, photovoltaic devices, and emitters to replace lead halide perovskites, owing to their nontoxicity and chemical stability. However, most double perovskites always exhibit low photoluminescence quantum efficiency (PLQE) due to the indirect bandgap structure or parity‐forbidden transition problem, limiting their further applications. Herein, the self‐trapped excitons emission of Cs2NaInCl6 by Sb‐doping, showing a blue emission with high PLQE of 84%, is improved. Further, Sb/Mn codoped Cs2NaInCl6 nanocrystals are successfully synthesized by the hot‐injection method, showing a tunable dual‐emission covering the white‐light spectrum. The studies of PL properties and dynamics reveal that an energy transfer process can occur between the self‐trapped excitons and dopants (Mn2+). The work provides a new perspective to design novel lead‐free double perovskites for realizing a unique white‐light emission.

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This paper discusses the implementation of mathematical functions such as exponentials, trigonometric functions, the sigmoid function and the perceptron function with molecular reactions in general, and DNA strand displacement reactions in particular. The molecular constructs for these functions are predicated on a novel representation for input and output values: a fractional encoding, in which values are represented by the relative concentrations of two molecular types, denoted as type-1 and type-0. This representation is inspired by a technique from digital electronic design, termed stochastic logic, in which values are represented by the probability of 1’s in a stream of randomly generated 0’s and 1’s. Research in the electronic realm has shown that a variety of complex functions can be computed with remarkably simple circuitry with this stochastic approach. This paper demonstrates how stochastic electronic designs can be translated to molecular circuits. It presents molecular implementations of mathematical functions that are considerably more complex than any shown to date. All designs are validated using mass-action simulations of the chemical kinetics of DNA strand displacement reactions.

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For solar cell applications, Sn-based hybrid perovskites have drawn particular interest due to their environmental friendliness. Here, a thin layer of C 60 pyrrolidine tris-acid (CPTA) is found essential for achieving high efficiency with planar solar cells of Sn-based perovskites. As a result, a power conversion efficiency of 7.40% is achieved for {en}FASnI 3 solar cells with a planar n-i-p architecture, and the device exhibits excellent stability in air. For the first time, highly efficient Sn-based hybrid perovskite solar cells on n-i-p architecture are achieved. A V oc of 0.72 V is highlighted as the highest V oc ever reported for FASnI 3 solar cells.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adfm.201903621. and sometimes even short-circuit the devices. Several strategies have been developed to protect the Sn-based perovskite, such as the adding of SnF 2 , [10] controlling the reducing atmosphere, [11] the forming of 2D/3D composite [12,13] or 3D hollow structures. [14][15][16][17] In order to achieve higher efficiency and stability, Sn-based perovskite have relied on mesoporous TiO 2 as the electron-selective layer. [18,19] The introduction of mesoporous TiO 2 makes manufacture process more complex, and the high-temperature needed for processing hampers the development of perovskitebased monolithic tandem devices and flexible wearable solar cells. [20,21] In contrast, the simplicity of the planar heterojunction indicates that a planar architecture is more technically feasible. [22] Besides, planar PSCs can be fabricated via solution processing at low temperatures (<150 °C), thus greatly reducing manufacturing costs. However, compared to the mesoporoustype PSC, its planar-type counterpart suffers from very low PCE, [23,24] probably due to the poor contact of the interfaces [25] and unsuitable charge transporting layer. [23] Here, we tried SnO 2 as the electron transport layer to fabricate a n-i-p planar-architecture, but was not successful. Then we introduced a hydrophilic derivative of fullerene, namely, the C 60 pyrrolidine tris-acid (CPTA) between SnO 2 and the perovskite. As a result, we achieved a power conversion efficiency above 7.40% for Sn-based perovskite devices with the planar architecture. This shows that not only mesoporous-architecture devices, but also n-i-p planar-architecture devices can be highly efficient in the Sn-based PSCs. Thanks to the CPTA layer in our planar Sn-based PSCs, we attained a V oc of 0.72 V, which represents the highest value ever reported for FASnI 3 solar cells. Results and DiscussionWe fabricated Sn-based PSCs with the planar n-i-p architecture (Figure 1a). A SnO 2 compact layer deposited on the fluorine-doped tin oxide (FTO) substrate was employed as an electron transport layer. C 60 pyrrolidine tris-acid (CPTA) was then deposited onto the SnO 2 -covered FTO substrate. Figure 1b shows the X-ray diffraction (XRD) pattern of the {en}FASnI 3 films. The peaks of FTO substrate are marked with black dots. ...