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Various isomers have been developed to regulate the morphology and reduce defects in state‐of‐the‐art perovskite solar cells (PSCs). To insight the structure‐function‐effect correlations for the isomerization of thiourea derivatives on the performance of the PSCs, we developed two thiourea derivatives [(3,5‐dichlorophenyl)amino]thiourea (AT) and N‐(3,5‐dichlorophenyl)hydrazinecarbothioamide (HB). Supported by experimental and calculated results, it was found that AT can bind with undercoordinated Pb2+ defect through synergistic interaction between N1 and C=S group with a defect formation energy of 1.818 eV, which is much higher than that from the synergistic interaction between two −NH− groups in HB and perovskite (1.015 eV). Moreover, the stronger interaction between AT and Pb2+ regulates the crystallization process of perovskite film to obtain a high‐quality perovskite film with high crystallinity, large grain size, and low defect density. Consequently, the AT‐treated FACsPbI3 device engenders an efficiency of 25.71 % (certified as 24.66 %), which is greatly higher than control (23.74 %) and HB‐treated FACsPbI3 devices (25.05 %). The resultant device exhibits a remarkable stability for maintaining 91.0 % and 95.2 % of its initial efficiency after aging 2000 h in air condition or tracking at maximum power point for 1000 h, respectively. [ABSTRACT FROM AUTHOR]

Tomographic synthetic aperture radar (TomoSAR) technology has demonstrated significant practical value in forest parameter extraction, accumulating a wealth of airborne data and research results over the years. This paper addresses the problem of TomoSAR underlying topography inversion in forested areas, where the complex vertical structure of forests contributes to diverse scattering mechanisms, making it difficult to determine the exact number of scatterers within each unit. To tackle this issue, we propose a TomoSAR underlying topography inversion method that combines density clustering with the multiple signal classification (MUSIC) technique. The proposed algorithm achieves superior estimation for the positions of unknown scatterers by utilizing eigenvalue density clustering to distinguish the signal and noise subspaces. A series of simulated experiments were conducted to showcase the robustness of the proposed algorithm in estimating scatterer phase centres under challenging conditions such as low signal-to-noise ratio and limited snapshots. Moreover, the practicality of the proposed algorithm in accurately reconstructing the underlying topography is validated by experimental results of real data obtained from the BioSAR 2008 campaign dataset. [ABSTRACT FROM AUTHOR]

Biogel‐based ionic devices have emerged as versatile platforms for broad applications in wearable electronics, healthcare monitoring and bioelectronic interfaces. Electronic functions derived from fully edible natural soft materials are particularly attractive to allow low cost, green, biocompatible and biodegradable devices in biomedical areas as well as smart food package. This work presents a gummy‐inspired protein eutectogel by simply soaking gelatin hydrogels into solutions of natural deep eutectic solvent (NADES) consisting of sorbitol and citric acid to allow solvent exchange. Compared with the gelatin hydrogel, this natural eutectogel (NEG) exhibited anti‐drying and anti‐freezing performance, remarkably improved adhesiveness, room temperature degradability, as well as high mechanical toughness. The soaking conditions were investigated to tune the softness and ionic conductivity of the NEG, which revealed that the water content and acid ratio could significantly impact on the gel properties. Additionally, the eutectogel thin film exhibited good humidity sensing capability with a wide linear detection range (22%–98% RH), in which a soft patch was further demonstrated for breath test to detect various respiration frequencies. Thus, we believe the concept of NEG combining biopolymers and NADES can be explored in a broad range of soft devices for sensing, bio‐adhesives, energy supply or drug delivery. [ABSTRACT FROM AUTHOR]

Advanced waveform design schemes have been widely employed for radar and sonar remote sensing analysis such as target detection and separation, where significant range sidelobe is a main factor that limits the improvement of analysis performance. As an extensional type of Golay complementary waveforms, complementary sets are a waveform design scenario of concern that shows more diversity in the design of transmission order, and results in a different distribution of range sidelobes. This work proposes an oversampled generalized Prouhet–Thue–Morse (OGPTM) method for the transmitted signal design of complementary sets, with comprehensive analysis to the influence on the sidelobe distribution. Based on this idea and our previous work, we further put forward a pointwise multiplication processor (PMuP) to integrate two delay-Doppler maps of oversampled complementary sets, which achieve much better sidelobe suppression performance on high-speed target detection with range migration. [ABSTRACT FROM AUTHOR]

Organic self‐assembled molecules (OSAMs) based hole‐transporting materials play a pivotal role in achieving highly efficient and stable inverted perovskite solar cells (IPSCs). However, the reported carbazol‐based OSAMs have serious drawbacks, such as poor wettability for perovskite solution spreading due to the nonpolar surface, worse matched energy arrangement with perovskite, and limited molecular species, which greatly limit the device performance. To address above problems, a novel OSAM [4‐(3,6‐glycol monomethyl ether‐9H‐carbazol‐9‐yl) butyl]phosphonic acid (GM‐4PACz) was synthesized as hole‐transporting material by introducing glycol monomethyl ether (GM) side chains at carbazolyl unit. GM groups enhance the surface energy of Indium Tin Oxide (ITO)/SAM substrate to facilitate the nucleation and growth of up perovskite film, suppress cation defects, release the residual stress at SAM/perovskite interface, and evaluate energy level for matching with perovskite. Consequently, the GM‐4PACz based IPSC achieves a champion PCE of 25.52 %, a respectable open‐circuit voltage (VOC) of 1.21 V, a high stability, possessing 93.29 % and 91.75 % of their initial efficiency after aging in air for 2000 h or tracking at maximum power point for 1000 h, respectively. [ABSTRACT FROM AUTHOR]

To simultaneously stabilize cesium lead triiodide (CsPbI3) precursor solution and passivate the defects in CsPbI3 film is greatly significant for achieving highly stable and efficient CsPbI3 perovskite solar cells (PSCs). Herein, an effective redox 4‐fluorobenzothiohydrazide (FBTH) is developed to stabilize the precursor solution and passivate iodine/lead‐related defects for high‐quality CsPbI3 film. The comprehensive research confirms that 1) a new compound FBTH‐I is obtained from an effective redox interaction between FBTH and molecular iodine (I2) in perovskite precursor solution, which can effectively impede the formation of I2 molecule and restrain I− migration in perovskite film by forming N–H···I bond; 2) FBTH‐I can also passivate Pb‐related defects via forming S···Pb interaction. Consequently, the CsPbI3 PSC based on FBTH‐treated precursor solution exhibits a fascinating power conversion efficiency (PCE) of 21.41%, which is one of the highest PCE values among the reported pure CsPbI3 PSCs so far, and an outstanding stability against the harsh conditions, such as thermal annealing and continuous light‐illumination. [ABSTRACT FROM AUTHOR]

The terrible shuttling of lithium polysulfides (LiPSs) is a major obstacle for commercializing lithium–sulfur (Li–S) batteries as high‐performance energy storage systems. In this study, a carbon‐based interlayer with effective suppression capability on the shuttle effect is developed by simply coating a well‐dispersed mixture of soybean protein isolate/MXene onto the acidified carbon paper (ACP). The resultant composite interlayer (SM@ACP) is able to synergistically diminish the shuttle effect through chemical adsorption and physical blocking. Meanwhile, this interlayer displays excellent conductivity and facilitates the diffusion of Li ions due to the composite coating to promote both electron/ion conduction as well as the porous structure of ACP. Benefiting from the unique properties of the composite interlayer, the as‐assembled Li–S batteries with SM@ACP interlayers show a great improvement in the cycling stability and rate performance, delivering a very low‐capacity decay rate of 0.071% per cycle at 0.5 C even after 800 cycles. This work provides a feasible route to realize rational design and commercial mass production of desirable interlayers for promoting the commercialization of Li–S batteries. [ABSTRACT FROM AUTHOR]

The ion/chemical‐based modulation feature of organic mixed ionic‐electronic conductors (OMIECs) are critical to advancing next generation bio‐integrated neuromorphic hardware. Despite achievements with polymeric OMIECs in organic electrochemical neuronal synapse (OENS). However, small molecule OMIECs based OENS has not yet been realized. Here, for the first time, we demonstrate an effective materials design concept of combining n‐type fused all‐acceptor small molecule OMIECs with subtle side chain optimization that enables robustly and flexibly modulating versatile synaptic behavior and sensing neurotransmitter in solid or aqueous electrolyte, operating in accumulation modes. By judicious tuning the ending side chains, the linear oligoether and butyl chain derivative gNR‐Bu exhibits higher recognition accuracy for a model artificial neural network (ANN) simulation, higher steady conductance states and more outstanding ambient stability, which is superior to the state‐of‐art n‐type OMIECs based OENS. These superior artificial synapse characteristics of gNR‐Bu can be attributed to its higher crystallinity with stronger ion bonding capacities. More impressively, we unprecedentedly realized n‐type small‐molecule OMIECs based OENS as a neuromorphic biosensor enabling to respond synaptic communication signals of dopamine even at sub‐μM level in aqueous electrolyte. This work may open a new path of small‐molecule ion‐electron conductors for next‐generation ANN and bioelectronics. [ABSTRACT FROM AUTHOR]