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Perovskite solar cells (PSCs) have experienced exceptional development in recent years, due to their outstanding photoelectronic properties and low‐cost solution processing. Many state‐of‐the‐art PSC designs have been effectively demonstrated using a stacked 3D perovskite/2D perovskite heterostructure, yet limitations arise due to the low conductivity of the 2D perovskite, the hidden buried interface of 3D perovskite, and halide ion migration within 3D/2D PSC device under operational bias. Here, these limitations are overcome by developing a novel and universal post‐synthetic metal (Zn2+) doping strategy and realizing 3D/2D PSCs with superior efficiency and stability. Informed by ab initio calculations and synchrotron fine structure experiments, it is revealed that the introduced zinc ions are energetically favored at interstitial crystal sites, subsequently hindering the migration of halide ions and producing a beneficial shift toward a more n‐type character in the buried 3D perovskite interface. Combined with extensive photophysical characterization, the Zn2+‐modified 3D/2D perovskite thin film is shown to strongly recover its photo‐carrier conductivity compared with the 3D/2D perovskite film, boosting the efficiency (22.90%) of PSCs while exhibiting improved humidity and operational stability. [ABSTRACT FROM AUTHOR]

Summary: This article investigates the issue of orbit coordination control for a class of multi‐spacecraft formation systems in presence of limited communication and external disturbance. To solve the limitation of communication sources, a dynamic event trigger (DET) mechanism is developed to reduce the communication frequency between the follower spacecrafts. Subsequently, we explore a robust DET mechanism‐based distributed self‐learning sliding mode control design, in which a variable learning intensity‐based iterative learning algorithm is designed to approximate and compensate space perturbation. This approach can guarantee an event triggering sequence without Zeno phenomenon and accurate coordination control for formation configuration simultaneously. Compared with the traditional event‐triggered control and other state‐of‐the‐art approaches, the distributed DET control scheme achieves higher control accuracy of formation configuration meanwhile requires less communication resource. Finally, a series of numerical simulations demonstrate the feasibility and superiority of the event triggered control method. [ABSTRACT FROM AUTHOR]

Metal halide perovskite light‐emitting diodes (PeLEDs) are expected to be the next‐generation display technology due to their unique optoelectronic properties. Currently, the external quantum efficiencies of PeLEDs based on solution‐processed fabrication methods already exceed 20%. However, there are still many challenges existing in solution‐based PeLEDs that inhibit their commercialization. Recently, vacuum deposition techniques of perovskites have drawn much attention because of the ability to grow dense and uniform large‐area perovskite films with precisely controlled thickness, which is compatible with state‐of‐the‐art organic LED manufacturing processes. Despite the promising prospects of vacuum‐based PeLEDs, some challenges remain to be addressed to achieve PeLEDs with both high efficiency and high stability that are required for practical applications such as active‐matrix displays. This requires precise control of the film morphology, composition, and interface during the deposition process through fine‐tuning of the substrate temperature, deposition rate, vacuum level, precursor formulation, and post‐treatment conditions. In this review, it focuses on the key requirements for vacuum‐processed PeLEDs, highlights the recent advances in materials and devices of PeLEDs, and emphasize vacuum evaporation methods as well as the corresponding device performance. Possible approaches to improve the efficiency and the long‐term operational stability of vacuum‐processed PeLEDs are discussed. [ABSTRACT FROM AUTHOR]

Core–shell perovskite nanocrystals (NCs) have emerged as a promising class of materials for optoelectronic applications due to their unique properties and stability. Although much research has been conducted on the shell growth mechanism and properties of the core–shell NCs, little is known about the role of shell thickness in determining their optical properties. Herein, a heteroepitaxial method is employed to prepare a series of core–shell FAPbBr3/CsPbBr3 NCs with different shell thicknesses. Through temperature‐dependent photoluminescence measurement, it is found that the electronic structure of core–shell FAPbBr3/CsPbBr3 NCs evolves from quasi‐type‐II to type‐I with the increase in shell thickness. This abnormal transition can be attributed to the thickened gradient alloy layer FA1‐xCsxPbBr3, which effectively relieves the lattice mismatch and releases strain in the NCs, resulting in variations in the bandgap between the core and the shell. Furthermore, the biexciton Auger lifetimes in these samples exhibit a non‐monotonic dependence on shell thickness, indicating the electronic structure transition. These results provide valuable insights into the relationship between shell thickness, electronic structure, and optical properties in core–shell perovskite NCs, which may offer guidance for the design of high‐performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

This paper investigates a performance‐adjustable prescribed performance control (PPC) policy under event‐triggered sampling for spacecraft attitude‐orbit coupled tracking with consideration of limited communications and performance constraints. Firstly, a logarithmic barrier Lyapunov function is introduced to derive the attitude‐orbit coupled tracking controller with guaranteed transient and steady‐state behaviors by applying the PPC algorithm. Then, to reduce the burden of the signal transmission under limited communications, the event‐triggered mechanism is applied to determine when the above attitude‐orbit coupled tracking controller updates. Furthermore, an indirect adaptive method with less computation that does not involve complex regression matrices or neural networks is designed to resist external disturbances. Compared with the traditional spacecraft control policies, the proposed strategy fully considers the state convergence performance, sampling performance, and calculation performance. The proposed one here can arbitrarily adjust the sampling performance and state convergence performance in an excellent trade‐off. Finally, a group of illustrative examples is organized to demonstrate the effectiveness of the proposed control policy. [ABSTRACT FROM AUTHOR]

The facile oxidation of Sn2+ to Sn4+ poses an inherent challenge that limits the efficiency and stability of tin‐lead mixed (Sn−Pb) perovskite solar cells (PSCs) and all‐perovskite tandem devices. In this work, we discover the sustainable redox reactions enabling self‐healing Sn−Pb perovskites, where their intractable oxidation degradation can be recovered to their original state under light soaking. Quantitative and operando spectroscopies are used to investigate the redox chemistry, revealing that metallic Pb0 from the photolysis of perovskite reacts with Sn4+ to regenerate Pb2+ and Sn2+ spontaneously. Given the sluggish redox reaction kinetics, V3+/V2+ ionic pair is designed as an effective redox shuttle to accelerate the recovery of Sn−Pb perovskites from oxidation. The target Sn−Pb PSCs enabled by V3+/V2+ ionic pair deliver an improved power conversion efficiency (PCE) of 21.22 % and excellent device lifespan, retaining nearly 90 % of its initial PCE after maximum power point tracking under light for 1,000 hours. [ABSTRACT FROM AUTHOR]

Formamidinium lead iodide quantum dots (QDs) show great potential for solar cell applications but suffer from restricted charge transfer due to the insulating nature of their ligand shell. Management of the surface properties and resultant energy band alignment is the key to efficient and stable QD solar cells. Herein, an advance in QD surface passivation by introducing tailored multifunctional ligands (glycocyamine (GLA)) to the FAPbI3 QD surface is demonstrated. The incorporation of GLA ligands can partly substitute the native long‐chain insulating ligands and effectively reduce the non‐radiative recombination loss induced by surface trap states. Notably, the introduction of GLA ligands beneficially shifts the band offsets of the QD films and generates a homojunction structure with a cascading energy band alignment in the QD layers, promoting favorable charge transport and boosting the device's performance. As a result, a record‐high power conversion efficiency (PCE) of 15.34% with improved open‐circuit voltage and fill factor is achieved. Moreover, the GLA‐assisted surface passivation boosts the device stability, in which over 80% and 75% of the original PCEs are maintained after storing the devices for 5500 h in ambient air and 768 h under continuous 1‐sun illumination, respectively. [ABSTRACT FROM AUTHOR]

This article addresses the high‐accuracy intelligent trajectory tracking control problem of a quadrotor unmanned aerial vehicle (UAV) subject to external disturbances. The tracking error systems are first reestablished by utilizing the feedforward control technique to compensate for the raw error dynamics of the quadrotor UAV. Then, two novel appointed‐fixed‐time observers are designed for the processed error systems to reconstruct the disturbance forces and torques, respectively. And the observation errors can converge to origin within the appointed time defined by users or designers. Subsequently, two novel control policies are developed utilizing reinforcement learning methodology, which can balance the control cost and control performance. Meanwhile, two critic neural networks are used to replace the traditional actor‐critic networks for approximating the solutions of Hamilton–Jacobi–Bellman equations. More specifically, two novel weight update laws are developed. They can not only update the weights of the critic neural networks online, but also avoid utilizing the persistent excitation condition innovatively. And that the ultimately uniformly bounded stability of the whole control system is proved according to Lyapunov method by utilizing the proposed reinforcement learning‐based control polices. Finally, simulation results are presented to illustrate the effectiveness and superior performances of the developed control scheme. [ABSTRACT FROM AUTHOR]

Herein, we reported that the platinum (Pt) clusters encapsulated into sodalite (SOD) zeolite as catalyst exhibited 100 % selectivity at 100 % conversion in the selective hydrogenation of p‐chloronitrobenzene to p‐chloroaniline via hydrogen spillover. The direct interaction between p‐chloronitrobenzene and encapsulated Pt was prevented by the shape selectivity of SOD zeolite, reactants were thereby adsorbed onto zeolite outer surface to facilitate the hydrogenation proceeding by hydrogen spillover process. The further kinetic study and DFT calculation showed the excellent catalytic selectivity was ascribed to the much faster rate of hydrogenation of adsorbed nitro group than that of adsorbed C−Cl group. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic exacerbates challenges faced by human immunodeficiency virus patients, who are at heightened risk for infection due to compromised immune systems. This study aims to develop a reliable, home‐based point‐of‐care testing (POCT) tool for early screening of acquired immunodeficiency syndrome (AIDS) coinfected with Talaromyces marneffei infection. Employing a "From weak to strong" deduction strategy for feature selection, data from 464 AIDS patients across four cohorts between February 5th, 2014, and January 8th, 2022, are analyzed. The top three features consistently observed are D‐dimer, cluster of differentiation 4+, and aspartate transaminase. Based on these features, the simplest risk‐scoring model is constructed, with the area under the receiver operating characteristic curve values of 0.91, 0.80, and 0.69 in the hold‐out cohort, external cohort 1, and external cohort 2, respectively. This "From weak to strong" deduction strategy identifies advantageous clinical features, enabling the development of simplified clinical risk scores with multiple biomarkers. To facilitate practical implementation, enhanced POCT tools are introduced, specifically a strip with segmented testing capabilities that demonstrates sensitivity and strong correlation with clinical scoring models. Furthermore, an open‐access website and a free Android mobile app are created to support community utilization. The findings underscore the effectiveness of the innovative deduction strategy and enhanced test strips, which enable bedside measurements without laboratory dependency. [ABSTRACT FROM AUTHOR]

Performance of blue solution‐processed perovskite light‐emitting diodes (LEDs) is limited by availability of blue perovskite materials. Herein, 4‐(trifluoromethyl)benzoyl ammonium bromide (4‐TMBABr) is used with abundant NH and CO groups to passivate the defects and produce highly stable PEAxPA2‐x(CsPbBr3)n‐1PbBr4 perovskites for blue LED applications. The NH group in the 4‐TMBABr suppresses the Br‐ion mismatch through hydrogen bonds (N‐H···Br) and CO group coordinates the unsaturated lead dangling bonds (CO:Pb). The effective defect passivation by 4‐TMBABr reduces the nonradiative recombination in the perovskite films, hence enhancing its optical performance. In the LED structure, the sodium bis(trifluoromethanesulfonyl)imide (SBTI) modified NiOx films are used to improve the hole transport and to inhibit the fluorescence quenching of the perovskite layer. The dual‐defect manipulation strategy is advantageous for producing efficient and spectrally stable blue perovskite LEDs, and the authors demonstrate an LED with maximum luminance of 1094 cd m−2 and external quantum efficiency of 10.3%. This work can inform and underpin future development of blue perovskite LEDs with highly efficient and stabile performance. [ABSTRACT FROM AUTHOR]

Metal halide perovskite quantum dots (QDs) have emerged as potential materials for high brightness, wide color gamut, and cost‐effective backlight emission due to their high photoluminescence quantum yields, narrow emission linewidths, and tunable bandgaps. Herein, CsPbX3/SBA‐15 nanocomposites are prepared with outstanding optical properties and high stability through an in situ growth strategy using mesoporous silica particles. According to finite‐difference time‐domain simulations, the mesoporous structure provides a strong waveguide effect on perovskite QDs and the uniform dispersion suppresses reabsorption losses, improving the overall photoconversion efficiency of perovskite QDs. The as‐fabricated perovskite monochromatic light‐emitting diode (LED) has a maximum luminous efficiency of 183 lm W−1, which is the highest for monochromatic perovskite LEDs reported to date. A further benefit of this work is that the white devices, which combine the green and red perovskite nanocomposites with commercial blue LED, exhibit a high luminous efficiency of 116 lm W−1 and a wide color gamut (125% for NTSC and 94% for Rec. 2020) with coordinates of (0.33,0.31). [ABSTRACT FROM AUTHOR]

Stable all‐inorganic CsPbX3 perovskite nanocrystals (PNCs) with high optical yield can be used in combination with graphene as photon sensors with high responsivity (up to 106 A W−1) in the VIS‐UV range. The performance of these perovskite/graphene field effect transistors (FET) is mediated by charge transfer processes at the perovskite – graphene interface. Here, the effects of high electric (up to 3000 kV cm−1) and magnetic (up to 60 T) fields applied perpendicular to the graphene plane on the charge transfer are reported. The authors demonstrate electric‐ and magnetic‐field dependent charge transfer and a slow (>100 s) charge dynamics. Magneto‐transport experiments in constant (≈0.005 T s−1) and pulsed (≈1000 T s−1) magnetic fields reveal pronounced hysteresis effects in the transfer characteristics of the FET. A magnetic time is used to explain and model differences in device behavior under fast (pulsed) and slowly (continuous) changing magnetic fields. The understanding of the dynamics of the charge transfer in perovskite/graphene heterostructures developed here is relevant for exploitation of these hybrid systems in electronics and optoelectronics, including ultrasensitive photon detectors and FETs for metrology. [ABSTRACT FROM AUTHOR]

Self‐assembly of nanocrystals into controlled structures while uncompromising their properties is one of the key steps in optoelectronic device fabrication. Herein, zigzag CsPbBr3 perovskite nanocrystals are demonstrated with a precise number of components with nanocube morphology, these can be successfully obtained through a dipole‐induced self‐assembly process. The addition of a trace amount of deionized water facilitates the transfer from CsPbBr3 nanocubes to intermediates of CsPb2Br5 and Cs3In2Br9, which then fastly release reaction monomers leading to further homogenous nucleation of CsPbBr3 nanocubes, followed by the formation of zigzag CsPbBr3 nanocrystals through a dipole‐induced self‐assembly process. Dipole moment along <110> axis is found to be the driving force for the assembly of nanocubes into zigzag nanocrystals. The zigzag CsPbBr3 nanocrystals exhibit desirable optical properties comparable to their nanocube counterparts and offer advantages for amplified spontaneous emission and lasing applications with low pump thresholds of 3.1 and 6.02 µJ cm−2, respectively. This study not only develops a strategy for producing highly controlled zigzag perovskite nanocrystals and provides insights on the dipole‐induced self‐assembly mechanisms, but also opens an avenue for their application in lasing. [ABSTRACT FROM AUTHOR]

Quasi‐2D Ruddlesden‐Popper perovskites receive tremendous attention for application in light‐emitting diodes (LEDs). However, the role of organic ammonium spacers on perovskite film has not been fully‐understood. Herein, a spacer cation assisted perovskite nucleation and growth strategy, where guanidinium (GA+) spacer is introduced into the perovskite precursor and at the interface between the hole transport layer (HTL) and the perovskite, to achieve dense and uniform perovskite films with enhanced optical and electrical performance is developed. A thin GABr interface pre‐formed on HTL provides more nucleation sites for perovskite crystal; while the added GA+ in perovskite reduces the crystallization rate due to strong hydrogen bonding interacts with intermediates, which promotes the growth of enhanced‐quality quasi‐2D perovskite films. The ionized ammonium group (NH3+) of GA+ also favors formation of polydisperse domain distribution, and amine or imine (NH2 or NH) group interact with perovskite defects through coordination bonding. The spacer cation assisted nucleation and growth strategy is advantageous for producing efficient and high‐luminance perovskite LEDs, with a peak external quantum efficiency of over 20% and a luminance up to 100 000 cd m−2. This work can inform and underpin future development of high‐performance perovskite LEDs with concurrent high efficiency and brightness. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have witnessed an unprecedentedly rapid development, especially in terms of power conversion efficiency (PCE). However, the solution‐processed perovskite films inevitably possess numerous crystallographic defects (e.g., halide vacancies), which has been shown to incur non‐radiative charge recombination and ion migration, thus limiting the enhancement of the PCE and stability of PSCs. Here, a novel dual metal (i.e., divalent and monovalent metal ions) modification strategy is reported for simultaneously reducing the defects, immobilizing the halide anions, and preventing ion loss from perovskite during post‐annealing process. Accordingly, this strategy significantly reduces non‐radiative recombination, enhancing the PCE by ≈12% and mitigating the current density‐voltage (J–V) hysteresis effect in resultant devices compared to undoped counterparts. As a result, a champion PCE exceeding 22% and a high open‐circuit voltage (Voc) of 1.16 V is obtained for dual metal ions‐modified PSCs. The optimized devices also exhibit extended lifespan upon the dual metal treatment. The study provides a new defect engineering strategy toward more efficient and stable perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) of formamidinium lead triiodide (FAPbI3) perovskite hold great potential, outperforming their inorganic counterparts in terms of phase stability and carrier lifetime, for high‐performance solar cells. However, the highly dynamic nature of FAPbI3 QDs, which mainly originates from the proton exchange between oleic acid and oleylamine (OAm) surface ligands, is a key hurdle that impedes the fabrication of high‐efficiency solar cells. To tackle such an issue, here, protonated‐OAm in situ to strengthen the ligand binding at the surface of FAPbI3 QDs, which can effectively suppress the defect formation during QD synthesis and purification processes is selectively introduced. In addition, by forming a halide‐rich surface environment, the ligand density in a broader range for FAPbI3 QDs without compromising their structural integrity, which significantly improves their optoelectronic properties can be modulated. As a result, the power conversion efficiency of FAPbI3 QD solar cells (QDSCs) is enhanced from 7.4% to 13.8%, a record for FAPbI3 QDSCs. Furthermore, the suppressed proton exchange and reduced surface defects in FAPbI3 QDs also enhance the stability of QDSCs, which retain 80% of the initial efficiency upon exposure to ambient air for 3000 hours. [ABSTRACT FROM AUTHOR]

It is challenging to establish single metal atoms with a uniform coordination environment at targeted sites of a zeolite. In this study, single platinum atoms were selectively encaged in the six‐membered rings of sodalite (SOD) cages within Y zeolite using a template‐guiding strategy. During the in situ synthesis process, template molecules were designed to occupy supercages and thereby force coordinated platinum species into SOD cages. Subsequent control of the post‐treatment conditions yielded the Y zeolite with selectively encaged single platinum atoms, denoted Pt@Y‐SOD. The Pt@Y‐SOD catalyst had good stability and excellent catalytic selectivity in the semihydrogenation reaction, and it exhibited interesting thiophene and carbon monoxide resistance in this transformation because interactions with these poisons are weakened by the configuration of the encaged single platinum atoms. [ABSTRACT FROM AUTHOR]

The problem of simultaneous estimation of states and uncertainties by using limited information is investigated in this article. A sampled‐data learning observer (SLO) is presented for linear time‐invariant continuous systems, which can achieve successful estimation while only needs intermittent sampled‐data, saves computing resources, and does not require persistent excitation signals. The observer's demand for continuous measurement is reduced, that is, limited‐information is sufficient. Notably, the uncertainty estimation is performed by a learning equation with only simple addition operations, which is particularly suitable for actual digital system scenarios. Simulation results illustrate the effectiveness of the proposed SLO. [ABSTRACT FROM AUTHOR]

Simplified perovskite solar cells (PSCs) were fabricated with the perovskite layer sandwiched and encapsulated between carbon‐based electron transport layer (ETL) and counter electrode (CE) by a fully blade‐coated process. A self‐assembled monolayer of amphiphilic silane (AS) molecules on transparent conducting oxide (TCO) substrate appeals to the fullerene ETL deposition and preserves its integrity against the solvent damage. The AS serves as a "molecular glue" to strengthen the adhesion toughness at the TCO/ETL interface via robust chemical interaction and bonding, facilitating the interfacial charge extraction, increasing PCEs by 77 % and reducing hysteresis. A PCE of 18.64 % was achieved for the fully printed devices, one of the highest reported for carbon‐based PSCs. AS‐assisted interfacial linkage and carbon‐material‐assisted self‐encapsulation enhance the stability of the PSCs, which did not experience performance degradation when stored at ambient conditions for over 3000 h. [ABSTRACT FROM AUTHOR]

Inorganic perovskite nanocrystals (NCs) have demonstrated a number of unique optical and electronic properties for optoelectronic applications. However, the physical properties of these nanostructures, such as the dynamics of charge carriers on different timescales and their effect on the optical recombination of carriers, are not yet fully understood. This work reports on a slow (>1 s) reversible quenching of the NC photoluminescence due to a light‐induced Stark effect involving defects on the surface of the NCs and the redistribution of photoexcited carriers onto the NC surface. This phenomenon can influence the operation of optoelectronic devices based on these NCs, including hybrid photosensors based on graphene decorated with inorganic perovskite NCs, revealing their prospects and limitations. [ABSTRACT FROM AUTHOR]

Core/shell structured metal halide perovskite nanocrystals (NCs) are emerging as a type of material with remarkable optical and electronic properties. Research into this field has been developing and expanding rapidly in recent years, with significant advances in the studies of the shell growth mechanism and in understanding of properties of these materials. Significant enhancement of both the stability and the optical performance of core/shell perovskite NCs are of particular importance for their applications in optoelectronic technologies. In this review, the recent advances in core/shell structured perovskite NCs are summarized. The band structures and configurations of core/shell perovskite NCs are elaborated, the shell classification and shell engineering approaches, such as perovskites and their derivative shells, semiconductor shell, oxide shell, polymer shell, etc. are reviewed, and the shell growth mechanisms are discussed. The prospective of these NCs in lighting and displays, solar cells, photodetectors, and other devices is discussed in the light of current knowledge, remaining challenges, and future opportunities. [ABSTRACT FROM AUTHOR]

Lead halide perovskite nanocrystals (PeNCs) are promising materials for applications in optoelectronics. However, their environmental instability remains to be addressed to enable their advancement into industry. Here the development of a novel synthesis method is reported for monodispersed PeNCs coated with all inorganic shell of cesium lead bromide (CsPbBr3) grown epitaxially on the surface of formamidinium lead bromide (FAPbBr3) NCs. The formed FAPbBr3/CsPbBr3 NCs have photoluminescence in the visible range 460–560 nm with narrow emission linewidth (20 nm) and high optical quantum yield, photoluminescence quantum yield (PLQY) up to 93%. The core/shell perovskites have enhanced optical stability under ambient conditions (70 d) and under ultraviolet radiation (50 h). The enhanced properties are attributed to overgrowth of FAPbBr3 with all‐inorganic CsPbBr3 shell, which acts as a protective layer and enables effective passivation of the surface defects. The use of these green‐emitting core/shell FAPbBr3/CsPbBr3 NCs is demonstrated in light‐emitting diodes (LEDs) and significant enhancement of their performance is achieved compared to core only FAPbBr3‐LEDs. The maximum current efficiency observed in core/shell NC LED is 19.75 cd A‐1 and the external quantum efficiency of 8.1%, which are approximately four times and approximately eight times higher, respectively, compared to core‐only devices. [ABSTRACT FROM AUTHOR]

Metal halide perovskite nanocrystals (NCs) have shown significant potential in light‐emitting applications due to the unique luminous properties, such as high color purity, tunability, and solution processability. However, the large‐scale production of perovskite NCs with high‐quality for meeting the commercial applications is still a challenge. Herein, a facile room‐temperature synthesis of ten‐gram‐scale FAPbX3 (FA+ = HC(NH2)2+, X = Br, or mixed halide system Cl/Br and Br/I) NCs by a high‐power ultrasonic‐assisted strategy and the electroluminescence for light‐emitting diodes (LEDs) is reported. The uniform high‐power radiation avoids the adverse effects caused by heating and stirring unevenness, and no inert gas is needed in the reaction process. Meanwhile, the room temperature reaction reduces the crystallization rate of the NCs, leading to the successful synthesis of ten‐gram‐scale high‐quality FAPbX3 perovskite NCs. The resulting NCs show size‐focus distribution and high photoluminescence quantum yields of 93%, and the adjustable photoluminescence spectra from 453 to 695 nm by manipulating halide compositions. Attributed to the acquired FAPbBr3 NCs, a high‐efficiency green LED with the maximum current efficiency of 61.3 cd A−1 and external quantum efficiency of 14.1% is also obtained. [ABSTRACT FROM AUTHOR]

This paper presents the finite‐time attitude synchronization and tracking control method of undirected multi‐spacecraft formation with external disturbances. First, a modified adaptive nonsingular fast terminal sliding mode surface (ANFTSMS) is designed by introducing a user‐defined function, both of which avoid the singularity problem and continuous sliding surface, and, therefore, can freely adjust relative weighting between angular velocity error and attitude error adaptively, such that the controller can provide sufficient maneuvers and precision. This provides designers with a new technique to adjust and improve formation control performance. Second, by applying the ANFTSMS associated with adaptation, two proposed decentralized ANFTSM‐controllers provide finite‐time convergence, robustness to disturbance, and chattering free for continuous design. Finally, simulation results validate the proposed algorithms. [ABSTRACT FROM AUTHOR]

Abstract: Platinum nanoparticles encapsulated into zeolite Y (Pt@Y catalyst) exhibit excellent catalytic selectivity in the hydrogenation of substituted nitroarenes to form the corresponding aromatic amines, even after complete conversion. With the hydrogenation of p‐chloronitrobenzene as a model, the role of zeolite encapsulation toward perfect selectivity can be attributed to constraint of the substrate adsorbed on the platinum surface in an end‐on conformation. This conformation results in the activation of only one adsorbed group, with little influence on the other one in the molecule. Owing to a much lower apparent activation energy of Pt@Y for the hydrogenation of a separately adsorbed nitro group than that of the adsorbed chloro group, the Pt@Y catalyst can prevent hydrodechlorination of p‐chloronitrobenzene under mild conditions. Moreover, such a conformation results in a reduced adsorption energy of target p‐chloroaniline on the platinum surface; thus suppressing the reactivity of hydrodechlorination of p‐chloroaniline to circumvent further C−Cl bond breakage. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a kind of styrylpyridine-containing polybenzoxazine was obtained via the Knoevenagel reaction between benzaldehyde and methylpyridine groups. The benzoxazine monomer (MPBC) containing the benzaldehyde and methylpyridine groups was synthesized firstly and its structure was characterized by Fourier transform infrared (FTIR) spectra, 1H NMR and 13C NMR. With the aid of differential scanning calorimetry, FTIR, and photoluminescent tests, the interesting curing behaviors were probed. The results showed that the ring-opening polymerization occurred at lower temperature, and the Knoevenagel reaction further took place at elevated temperature. The amine and phenol moieties were bonded together to form the styrylpyridine structure. Due to these special crosslinking structures, the corresponding polybenzoxazine exhibited excellent thermal stability, and had a special high char yield of 74.5%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40823. [ABSTRACT FROM AUTHOR]

An investigation on reaction scheme and kinetics for ethanol steam reforming on skeletal nickel catalysts is described. Catalytic activity of skeletal nickel catalyst for low-temperature steam reforming has been studied in detail, and the reasons for its high reactivity for H2 production are attained by probe reactions. Higher activity of water gas shift reaction and methanation contributes to the low CO selectivity. Cu and Pt addition can promote WGSR and suppress methanation, and, thus, improve H2 production. A reaction scheme on skeletal nickel catalyst has been proposed through temperature programmed reaction spectroscopy experiments. An Eley-Rideal model is put forward for kinetic studies, which contains three surface reactions: ethanol decomposition, water gas shift reaction, and methane steam reforming reaction. The kinetics was studied at 300-400°C using a randomized algorithms method and a least-squares method to solve the differential equations and fit the experimental data; the goodness of fit obtained with this model is above 0.95. The activation energies for the ethanol decomposition, methane steam reforming, and water gas shift reaction are 187.7 kJ/mol, 138.5 kJ/mol and 52.8 kJ/mol, respectively. Thus, ethanol decomposition was determined to be the rate determining reaction of ethanol steam reforming on skeletal nickel catalysts. © 2013 American Institute of Chemical Engineers AIChE J 60: 635-644, 2014 [ABSTRACT FROM AUTHOR]

The synthesis and utilization of an α-Mn2O3 nanocrystal catalyst for methanol-to-olefin reaction is described. A methanol conversion of 35% and a maximum selectivity of 80% toward ethylene were obtained at 250°C. In particular, formaldehyde, a primary intermediate for the reaction, was used to produce ethylene via a coupling reaction. A conversion of 45% and a selectivity of 66% to ethylene were achieved at 150°C in a formaldehyde stream. In situ diffuse reflectance infrared Fourier transform spectra reveal the formation of the surface CH2-containing species during reaction, which implies that the main pathway for formaldehyde coupling is probably through interactions of those intermediates. In addition, the weakly adsorbed oxygen on the α-Mn2O3 nanocrystal surface was found to play an important role in this reaction. © 2012 American Institute of Chemical Engineers AIChE J, 2012 [ABSTRACT FROM AUTHOR]

This article describes a strategy for increasing oxygen storage capacity (OSC) of ethanol steam reforming (ESR) catalysts. Sintering and carbon deposition are major defects of nickel-based catalysts for ESR; tuning oxygen mobility (OM) of CeO2-based supports can overcome these drawbacks and promote H2 production. We have successfully increased OSC and OM by adding Mg into the lattice of Ni/CeO2 to promote H2 production in ESR. The insertion of Mg into the CeO2 lattice efficiently promotes the reduction of Ce4+ according to X-ray powder diffraction (XRD) and temperature-programmed reduction (TPR) analysis. Mg-modified Ni/CeO2 catalysts have larger OSC and smaller nickel crystallite size compared with bare Ni/CeO2. The optimal Mg addition is 7 mol % (Ni/7MgCe) with the best OM. We also present evidence indicating that Mg addition significantly promotes ethanol conversion and H2 production in ESR, and that Ni/7MgCe yields the best performance due to the high OM of the support. These Mg-modified catalysts also produce less carbon deposition compared with Ni/CeO2, and the amount of deposited carbon decreases with increasing Mg addition. Ni/7MgCe has the best resistance to carbon deposition owing to the excellent OM. © 2011 American Institute of Chemical Engineers AIChE J, 2012 [ABSTRACT FROM AUTHOR]

1. It is reported thatα1-receptors and adenosine A1-receptors are involved in the ischaemic preconditioning (PC) effect on infarct size (IS). However, it is still unclear to what extentα1-receptors and adenosine A1-receptors contribute to the mechanism of PC. Therefore, we investigated the extent of the contribution ofα1-receptors and adenosine A1 receptors to the PC effect on IS and examined the relationship between these receptors and protein kinase C.2. Infarct size was measured in rabbits subjected to 30 min ischaemia and 48 h reperfusion. Tyramine (Tyr) was intravenously administered before 30 min ischaemia in the absence or presence of bunazosin (BN,α1-receptor blocker) and staurosporine (ST), a protein kinase C inhibitor, respectively. R(-)N6-(2-phenylisapropyl)-adenosine (PIA), a selective adenosine A1 agonist, was intravenously administered before 30 min ischaemia in the absence or presence of 8-p-sulphophenyltheophylline (8SPT), an adenosine blocker and ST, respectively. In the PC groups, BN, BN + PIA, 8SPT, 8SPT + Tyr or placebo saline was injected before or during PC.3. Both Tyr and PIA reduced the IS, which was blocked by BN and 8SPT, respectively. The IS-reducing effect of Tyr or PIA was blocked by ST. The IS-reducing effect of PC was completely blocked by BN and 8SPT, respectively. The blocking effect of BN on the IS-reducing effect of PC was abolished by adding PIA during PC ischaemia. The blocking effect of 8SPT on the IS-reducing effect of PC was abolished by adding Tyr before PC ischaemia.4. These data suggest that anα1-receptor dependent pathway exists and an adenosine A1-receptor dependent pathway, stimulation of both of which activates protein kinase C, then reduces the IS. However, exclusive stimulation of a singleα1-receptor dependent pathway or a single adenosine A1-receptor dependent pathway alone is not sufficient but the summation of these pathways is required to achieve a PC effect on IS in rabbits. [ABSTRACT FROM AUTHOR]

Recent years have witnessed an incredibly high fever in metal halide perovskite materials due to their promising applications in a wide range of optoelectronic applications. The morphologies and optoelectronic properties of the perovskite layers play critical roles in affecting the optoelectronic performances. This review summarizes the recent advances in the fabrication of a variety of perovskite morphologies and their promising progress achieved in different optoelectronic applications, including solar cells, light‐emitting diodes, photodetectors, lasers, photocatalysis, X‐ray detectors/imagers, and luminescent solar concentrators. Several blossoming representatives, including 0D perovskite quantum dots, 1D perovskite nanowires, 2D perovskite nanosheets/nanoplatelets, and 3D textured perovskite assemblies (i.e., cuboid‐like, inverse opal‐like, coral‐like, or maze‐like morphologies, etc.), are highlighted to demonstrate their fascinating properties and outstanding capabilities for efficient optoelectronic applications. Finally, a perspective on the remaining challenges and future directions of fabricating unique perovskite morphologies for next‐generation high‐performance optoelectronic devices is provided. [ABSTRACT FROM AUTHOR]

Metal halide perovskites emerge as promising semiconductors for optoelectronic devices due to ease of fabrication, attractive photophysical properties, their low cost, highly tunable material properties, and high performance. High‐quality thin films of metal halide perovskites are the basis of most of these applications including solar cells, light‐emitting diodes, photodetectors, and electronic memristors. A typical fabrication method for perovskite thin films is the solution method, which has several limitations in device reproducibility, adverse environmental impact, and utilization of raw materials. Thermal evaporation holds great promise in addressing these bottlenecks in fabricating high‐quality halide perovskite thin films. It also has high compatibility with mass‐production platforms that are well‐established in industries. This review first introduces the basics of the thermal evaporation method with a particular focus on the critical parameters influencing the thin film deposition. The research progress of the fabrication of metal halide perovskite thin films is further summarized by different thermal evaporation approaches and their applications in solar cells and other optoelectronic devices. Finally, research challenges and future opportunities for both fundamental research and commercialization are discussed. [ABSTRACT FROM AUTHOR]

1. It is reported that alpha1-receptors and adenosine A1-receptors are involved in the ischaemic preconditioning (PC) effect on infarct size (IS). However, it is still unclear to what extent alpha1-receptors and adenosine A1-receptors contribute to the mechanism of PC. Therefore, we investigated the extent of the contribution of alpha1-receptors and adenosine A1 receptors to the PC effect on IS and examined the relationship between these receptors and protein kinase C. 2. Infarct size was measured in rabbits subjected to 30 min ischaemia and 48 h reperfusion. Tyramine (Tyr) was intravenously administered before 30 min ischaemia in the absence or presence of bunazosin (BN, alpha1-receptor blocker) and staurosporine (ST), a protein kinase C inhibitor, respectively. R(-)N6-(2-phenylisapropyl)-adenosine (PIA), a selective adenosine A1 agonist, was intravenously administered before 30 min ischaemia in the absence or presence of 8-p-sulphophenyltheophylline (8SPT), an adenosine blocker and ST, respectively. In the PC groups, BN, BN + PIA, 8SPT, 8SPT + Tyr or placebo saline was injected before or during PC. 3. Both Tyr and PIA reduced the IS, which was blocked by BN and 8SPT, respectively. The IS-reducing effect of Tyr or PIA was blocked by ST. The IS-reducing effect of PC was completely blocked by BN and 8SPT, respectively. The blocking effect of BN on the IS-reducing effect of PC was abolished by adding PIA during PC ischaemia. The blocking effect of 8SPT on the IS-reducing effect of PC was abolished by adding Tyr before PC ischaemia. 4. These data suggest that an alpha1-receptor dependent pathway exists and an adenosine A1-receptor dependent pathway, stimulation of both of which activates protein kinase C, then reduces the IS. However, exclusive stimulation of a single alpha1-receptor dependent pathway or a single adenosine A1-receptor dependent pathway alone is not sufficient but the summation of these pathways is required to achieve a PC effect on IS in rabbits.