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Novel optoelectronic and photovoltaic devices are promising, exploiting MoSi2N4‐based van der Waals (vdW) heterostructures. Herein, six vertical XSi2N4/Cs2SnI6 (X = Cr, Mo, W) heterostructures are constructed and the atomic structure, stability, and optoelectronic properties via first‐principles calculations are investigated. The results of binding energies indicate that XSi2N4/SnI4 is energetically favorable to be established compared to the XSi2N4/CsI. Computed charge density differences show that at the XSi2N4/SnI4 interface, there is no significant charge migration or rearrangement, making it unsuitable for use in charge transport devices. It is worth noticing that the built‐in electric field induced by electron transfer from CsI to the XSi2N4 layer prevents light‐induced electron and hole recombination, thereby improving carrier lifetime. Furthermore, the CrSi2N4/CsI heterostructure exhibits a wider range of visible light absorption, demonstrating its potential for applications in photoelectronic devices. The electronic and optical properties of XSi2N4/Cs2SnI6 can be tuned through element substitution. The findings could provide useful guidance for designing XSi2N4/Cs2SnI6 photoelectronic and photovoltaic devices. [ABSTRACT FROM AUTHOR]

The semantic segmentation of drone LiDAR data is important in intelligent industrial operation and maintenance. However, current methods are not effective in directly processing airborne true-color point clouds that contain geometric and color noise. To overcome this challenge, we propose a novel hybrid learning framework, named SSGAM-Net, which combines supervised and semi-supervised modules for segmenting objects from airborne noisy point clouds. To the best of our knowledge, we are the first to build a true-color industrial point cloud dataset, which is obtained by drones and covers 90,000 m2. Secondly, we propose a plug-and-play module, named the Global Adjacency Matrix (GAM), which utilizes only few labeled data to generate the pseudo-labels and guide the network to learn spatial relationships between objects in semi-supervised settings. Finally, we build our point cloud semantic segmentation network, SSGAM-Net, which combines a semi-supervised GAM module and a supervised Encoder–Decoder module. To evaluate the performance of our proposed method, we conduct experiments to compare our SSGAM-Net with existing advanced methods on our expert-labeled dataset. The experimental results show that our SSGAM-Net outperforms the current advanced methods, reaching 85.3 % in mIoU, which ranges from 4.2 to 58.0 % higher than other methods, achieving a competitive level. [ABSTRACT FROM AUTHOR]

Interface engineering of the organo-lead halide perovskite devices has shown the potential to improve their efficiency and stability. In this study, the atomic, electronic, optical and transport characteristics of MAPbI3/Ga2O3 and MAPbCl3/Ga2O3 interfaces were investigated by using first-principles calculations. Eight different interfacial models were established and the interfacial properties were discussed. The results show that the PbI/O configuration exhibits the largest bonding strength out of all eight interfacial configurations. Owing to the larger interfacial interaction, the charge transfer at the PbI/O interface is significantly more than that at the other interfaces. The analysis of absorption spectra indicates that the Ga-terminated perovskite/Ga2O3 heterostructures are expected to have great potential for efficient optoelectronic applications. The analysis of transmission spectra shows that the MA/O configurations with more transmission peaks near the Fermi level exhibit lower resistance compared to others. The results of our study could help understand the interfacial engineering mechanism between perovskite and Ga2O3. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) have drawn much attention owing to their unique superiorities. The selection of electrode materials is significantly crucial as it influences SC performance. Defects such as low specific capacitance and poor rate performance need to be settled urgently to achieve enhanced SC performance. Here, we have developed an effective and facile strategy to prepare a binder-free nitrogen-doped graphene hydrogel (NDGH) as an electrode material. The electrochemical performance of NDGH was measured in three different electrolytes (2 M KOH, 1 M Na2SO4 and 1 M H2SO4), and it showed superior performance in 2 M KOH. NDGH had an outstanding specific capacitance of 224.1 F g−1 at 1 A g−1 and retained 80.7% of the capacitance at 10 A g−1. Meanwhile, NDGH possessed good cycling stability, with 93% capacitance retention after 6000 cycles. The contributions of surface-controlled and diffusion-controlled processes to NDGH capacitance were analyzed in different electrolytes. Compared with 1 M Na2SO4 (52%) and 1 M H2SO4 (13%), superior surface-controlled contribution was observed in the 2 M KOH (73%) electrolyte at 10 mV s−1. The symmetric supercapacitor (SSC) consisting of NDGH delivered an energy density of 14.3 W h kg−1 at a power density of 582.8 W kg−1 in the KOH electrolyte. These excellent electrochemical performance parameters could be achieved due to the synergistic effect of the multistage pore structure, nitrogen doping and binder-free hydrogel, which allow abundant electrochemical reactions to take place at the interface between the electrode materials and the electrolyte. This strategy may be further broadened to prominently enhance the specific capacitance and rate performance of graphene oxide. [ABSTRACT FROM AUTHOR]

MAX phases have exhibited diverse physical properties, inspiring their promising applications in several important research fields. The introduction of a chalcogen atom into a phase of MAX has further facilitated the modulation of their physical properties and the extension of MAX family diversity. The physical characteristics of the novel chalcogen-containing MAX 211 phase Zr2SeB and Zr2SeN have been systematically investigated. The present investigation is conducted from a multi-faceted perspective that encompasses the stability, electronic structure, and mechanical properties of the system, via the employment of the first-principles density functional theory methodology. By replacing C with B/N in the chalcogen-containing MAX phase, it has been shown that their corresponding mechanical properties are appropriately tuned, which may offer a way to design novel MAX phase materials with enriched properties. In order to assess the dynamical and mechanical stability of the systems under investigation, a thorough evaluation has been carried out based on the analysis of phonon dispersions and elastic constants conditions. The predicted results reveal a strong interaction between zirconium and boron or nitrogen within the structures of Zr2SeB and Zr2SeN. The calculated band structures and electronic density of states for Zr2SeB and Zr2SeN demonstrate their metallic nature and anisotropic conductivity. The theoretically estimated Pugh and Poisson ratios imply that these phases are characterized by brittleness. [ABSTRACT FROM AUTHOR]

To satisfy the functional requirements for next‐generation electronic and optoelectronic devices, diverse protocols have thus been developed for preparing transparent flexible electrodes (TFEs) of metallic nanowires with high flexibility and conductivity, while flexible electrodes with 3D configuration have become a burgeoning frontier. Herein, an innovative 3D network of silver nanorod–nanoparticle hybrids (Ag NNH) is realized by a facile aerosol jet printing (AJP) technique. A dynamic assembly mechanism based on the AJP of silver nanowires (AgNWs) ink is proposed, suggesting a favorable evaporation‐induced migration and assembly process along with the coalescence of deposited droplets. The initially formed Ag NNH random network optimizes the wettability, spreading, and pinning of the droplets, shaping the consecutive deposition behavior of the aerosol droplets for constructing the 3D Ag NNH networks. Planar micro‐supercapacitor (MSC) devices are developed using the Ag NNH network as flexible microelectrode, and a competitive areal capacitance performance has been demonstrated in comparison with other Ag‐based devices. It is envisioned that the as‐developed approach will provide an optional approach for developing future electronic and optoelectronic devices with fascinating hierarchical features. [ABSTRACT FROM AUTHOR]

2D MXene has attracted tremendous attention for developing high‐performance energy storage devices regarding its good metallicity and relatively large accessible surface area. However, the electrochemical performance of MXene‐related devices was hindered due to the pronounced self‐stacking characteristic of MXene. Herein, a convenient aerosol jet printing (AJP) process is developed for the synthesis of MXene nanospheres with crumpled and eccentric structures by modulating the migration and assembly of MXene nanosheets on heat substrate. The existing temperature gradient between the apex and the edge of the deposited droplet causes thermocapillary flows carrying MXene nanosheets toward the edge and the MXene nanosheets are further shaped and assembled along the droplet surface during the solvent evaporation. Interdigital microelectrodes of crumpled MXene nanospheres are tentatively developed for electrochemical performance characterization, a competitive areal capacitance performance is demonstrated in comparison with other MXene‐based devices. Importantly, this work highlights the great potential of the AJP technique for developing functional devices with fascinating hierarchical features as well as further extending applications in miniaturized and intelligent microelectronics. [ABSTRACT FROM AUTHOR]