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Summary: This paper proposes a wireline serial link transceiver for on‐package die‐to‐die links based on 12‐nm fin field‐effect transistor (FinFET) technology. The link is crucial for improving the computational performance of larger systems built from chiplets. To achieve high pin/energy efficiency and prevent traditional single‐ended signaling disadvantages, the transceiver adopts single‐ended ground‐reference signaling (GRS) to transfer information. To precompensate for the frequency‐dependent loss, retain the advantages of GRS, and avoid the disadvantages of traditional AC‐coupled equalizer, the transmitter in the transceiver adopts a DC‐coupled switched‐capacitor charge pump equalizer that can transmit GRS and its equilibrium value can be adjusted according to the channel attenuation. This paper proposes a method for timing de‐skew using digital control delay lines to eliminate the timing skew between data and the clock. In addition, this paper presents a duty cycle corrector to avoid duty cycle distortion, with an adjustment range of 44.5% to 52% and a power dissipation of only 30 μW. The transceiver has an area of 1.016 × 0.676 mm2, including one clock lane link and four data lane links. At a nominal 0.8‐V power supply voltage, the aggregate eye‐opening of the measured 25 Gb/s data on an organic substrate channel with an attenuation of −2.2 dB over 6 mm is 0.675 UI, with a bit error rate (BER) of less than 10−12 and an energy efficiency of 1.01 pJ/bit. [ABSTRACT FROM AUTHOR]

Shape editability combined with a self‐healing capability and long‐term cycling durability are highly desirable properties for wearable supercapacitors. Most wearable supercapacitors have rigid architecture and lack the capacity for editability into desirable shapes. Through sandwiching hydrogel electrolytes between two electrodes, a suite of wearable supercapacitors that integrate desirable properties namely: repeated shape editability, excellent self‐healing capability, and long‐term cycling durability is demonstrated. A strategy is proposed to enhance the long‐term cycling durability by utilizing hydrogel electrolytes with unique cross‐linking structures. The dynamic crosslinking sites are formed by quadruple H bonds and hydrophobic association, stabilizing the supercapacitors from inorganic ion disruption during charge–discharge processes. The fabricated supercapacitors result in the capacitance retention rates of 99.6% and 95.8% after 5000 and 10 000 charge–discharge cycles, respectively, which are much higher than others reported in the literature. Furthermore, the supercapacitor sheets can be repeatedly processed into various shapes without any capacitance loss. The supercapacitors exhibit a 95% capacitance retention rate after five cutting/self‐healing cycles, indicative of their excellent self‐healing performance. To demonstrate real‐life applicability, the wearable supercapacitors are successfully used to power a light‐emitting diode and an electronic watch. [ABSTRACT FROM AUTHOR]

Special attention should be devoted to the thermal stability of hybrid perovskite solar cells (PSCs), because they are often operated at elevated temperatures. However, effective strategies are lacking for manipulation of heat flow in PSCs to improve their thermal stability. Here, a holistic solution is reported for the rapid removal of dissipated heat within the absorber by introducing hexagonal boron nitride (h‐BN) inside and radiator fin outside of the device. This strategy significantly improves the thermal conductivity of perovskite and speeds up the heat transfer of device, which effectively reduces the cell temperature under illumination of simulated AM 1.5G standard spectrum by ≈6.5 °C. Regardless of device configurations, the corresponding PSCs exhibit prolonged lifetimes aged at different temperatures, continuously operated under white light‐emitting diode (LED) lamp or full‐spectrum illumination. Of particular note, the optimized h‐BN/Cu device with n–i–p structure keeps 88% and 93% of its initial PCE after 1776 h of 85 °C thermal aging and 2451 h of maximum power point (MPP) tracking, respectively, and the device with p–i–n structure maintains 96% and 92% of its original PCE after 1704 h of 85 °C thermal aging and 2164 h of MPP tracking. [ABSTRACT FROM AUTHOR]

Inspired by the unique band structure of CsPbBr3, we have developed an asymmetric Cl‐exchange strategy based on the CsPbBrxCl3‐x/TiO2 heterojunction‐type catalyst and achieved photocatalytic activation of C(sp3)−H bond using the toluene oxidation reaction as a proof‐of‐concept application. The anion exchange at the supported CsPbBr3 surface results in the CsPbBrxCl3‐x/TiO2 structure with an asymmetric distribution of halide. The resultant heterojunction‐type catalysts exhibit significantly improved photocatalytic activity for toluene oxidation reaction with the highest benzaldehyde production rate at 1874 μmol g−1 h−1 (∼4 times that of the naked CsPbBr3 nanocrystals). The remarkable photocatalytic performance can be ascribed to the improved carrier transport at CsPbBrxCl3‐x/TiO2 interface enabled by the unique band structure due to the asymmetric halide distribution, verified by the micro‐strain discovered through the X‐ray diffraction. This work demonstrates a new pathway to fabricate highly‐efficient halide perovskite heterojunction‐type catalysts for photocatalytic activation of C(sp3)−H bond. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: The heterojunction‐type structure has shown significant merits in tuning the optical properties and carrier physics. Inspired by the excellent absorption capability of halide perovskite materials for visible light, a series of CsPbBr3/TiO2 heterojunction‐type photocatalysts with various all‐inorganic‐perovskite/TiO2 ratios are successfully fabricated by the ligand‐assisted reprecipitation (LARP) method. The heterojunction structure extends the light absorption of TiO2 with good chemical and structural stability. A Pb‐O interaction at the CsPbBr3/TiO2 interface is observed by the XPS and confirmed by the TRPL showing improved interface carrier transport and stability. The heterojunction‐type catalyst shows drastically enhanced photocatalytic activity towards the direct oxidation of toluene with O2 molecule, as an important reaction for organic chemical synthesis. The optimized sample shows an activity of 2356 μmol·g–1·h–1 at 75 °C, 4 times of that of the naked CsPbBr3 nanocrystals, and 3 times of that of the bare TiO2. Based on the investigation with trapping agents, a reaction mechanism is hence proposed suggesting that the photo‐generated hole may be involved in the rate‐limiting step. This work demonstrates the potential of inorganic halide perovskite‐based heterojunction structure for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: The heterojunction‐type structure has shown significant merits in tuning the optical properties and carrier physics. Inspired by the excellent absorption capability of halide perovskite materials for visible light, a series of CsPbBr3/TiO2 heterojunction‐type photocatalysts with various all‐inorganic‐perovskite/TiO2 ratios are successfully fabricated by the ligand‐assisted reprecipitation (LARP) method. The heterojunction structure extends the light absorption of TiO2 with good chemical and structural stability. A Pb‐O interaction at the CsPbBr3/TiO2 interface is observed by the XPS and confirmed by the TRPL showing improved interface carrier transport and stability. The heterojunction‐type catalyst shows drastically enhanced photocatalytic activity towards the direct oxidation of toluene with O2 molecule, as an important reaction for organic chemical synthesis. The optimized sample shows an activity of 2356 μmol·g–1·h–1 at 75 °C, 4 times of that of the naked CsPbBr3 nanocrystals, and 3 times of that of the bare TiO2. Based on the investigation with trapping agents, a reaction mechanism is hence proposed suggesting that the photo‐generated hole may be involved in the rate‐limiting step. This work demonstrates the potential of inorganic halide perovskite‐based heterojunction structure for photocatalytic applications. [ABSTRACT FROM AUTHOR]

ABX3‐type halide perovskite nanocrystals (NCs) have been a hot topic recently due to their fascinating optoelectronic properties. It has been demonstrated that A‐site ions have an impact on their photophysical and chemical properties, such as the optical band gap and chemical stability. The pursuit of halide perovskite materials with diverse A‐site species would deepen the understanding of the structure–property relationship of the perovskite family. In this work we have attempted to synthesize rubidium‐based perovskite NCs. We have discovered that the partial substitution of Rb+ by Cs+ help to stabilize the orthorhombic RbPbBr3 NCs at low temperature, which otherwise can only be obtained at high temperature. The inclusion of Cs+ into the RbPbBr3 lattice results in highly photoluminescent Rb1−xCsxPbBr3 NCs. With increasing amounts of Cs+, the band gaps of the Rb1−xCsxPbBr3 NCs decrease, leading to a redshift of the photoluminescence peak. Also, the Rb1−xCsxPbBr3 NCs (x=0.4) show good stability under ambient conditions. This work demonstrates the high structural flexibility and tunability of halide perovskite materials through an A‐site cation substitution strategy and sheds light on the optimization of perovskite materials for application in high‐performance optoelectronic devices. Adding stability: Lead halide perovskite nanocrystals (NCs) attract tremendous attention due to their extraordinary optical properties. Herein, we show that the partial substitution of Rb+ by Cs+ helps to stabilize the orthorhombic RbPbBr3 NCs at low temperature, which otherwise could only be obtained at high temperature (above 300 °C, see figure). [ABSTRACT FROM AUTHOR]

A highly practical and step-economic α,β-dehydrogenation of carboxylic acids via enediolates is reported through the use of allyl-palladium catalysis. Dianions underwent smooth dehydrogenation when generated using Zn(TMP)2⋅2 LiCl as a base in the presence of excess ZnCl2, thus avoiding the typical decarboxylation pathway of these substrates. Direct access to 2-enoic acids allows derivatization by numerous approaches. [ABSTRACT FROM AUTHOR]

The telescoping of allyl-palladium catalyzed ketone dehydrogenation with organocuprate conjugate addition chemistry allows for the introduction of aryl, heteroaryl, vinyl, acyl, methyl, and other functionalized alkyl groups chemoselectively to a wide variety of unactivated ketone compounds via their enone counterparts. The compatibility of the dehydrogenation conditions additionally allows for efficient trapping of the intermediate enolate with various electrophiles. The utility of this approach is demonstrated by comparison to several previously reported multistep sequences. [ABSTRACT FROM AUTHOR]

Designing a highly active doped‐carbon‐based oxygen reduction reaction (ORR) electrocatalyst with optimal stability is a must if large‐scale implementations of fuel cells are to be realized. Developing controllable doping strategies is essential for achieving highly active catalysts. Herein, a facile doping strategy is developed by designing a precursor material with unique core–shell nanostructure, whereby the Materials Institute Lavoisier (MIL) metal–organic framework (MOF) and polyaniline are core and shell components, and serving as oxygen and nitrogen precursors, respectively. A novel hollow loofah‐like carbon tube (HLCT) catalyst is derived from precursor material with controllable heteroatom‐doping concentrations through modulating the mass ratio of MOF/aniline. The optimal HLCT‐1/2 catalyst, with a MOF/aniline mass ratio of 1/2, exhibits excellent ORR activity and stability in an alkaline medium. Remarkably, the half‐wave potential (0.88 V) and the current density (4.35 mA cm−2) at 0.85 V of HLCT‐1/2 catalyst surpass that of commercial Pt/C. Such superior catalytic properties can be attributed to the high specific surface area and abundant active sites of loofah‐shape carbon tubes. Moreover, the O dopant modulates the content and distribution of N species, leading to the enhanced adsorption strength of oxygen molecules on catalyst surface, promoting the activation of oxygen, and thus achieving higher electrocatalytic activity. [ABSTRACT FROM AUTHOR]

An abstract of the article "Diastereoselective Formation of Aziridines from Diazocarbonyl Compounds and N-(O-Pivaloylated D-Galactosyl)benzylideneamines and Ring-Opening Reactions with P-Toluenethiol" by Y. Zhao, and G. Wang, S. Zhou is presented.