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Antimony based chalcogenides, such as Sb2S3 and Sb2Se3, have garnered attention in the fields of photovoltaics and photodetection due to their excellent optoelectronic properties, environmental stability, simple composition, and low-cost fabrication. However, most of the efficient Sb2S3- and Sb2Se3-based devices are fabricated based on organic materials as the hole transport layer and costly metals as electrodes, which deteriorate the device stability, increase operational complexity and device fabrication cost. In this work, we propose the device engineering of Se and Sb to replace the organic interlayers and metal electrodes. An ultra-thin Sb2Se3 layer serves as the hole transport layer, formed through vacuum evaporation and in situ annealing. This approach enhances charge transport capacity and reduces leakage current. The optimized Sb2S3 photodiodes exhibit exceptional performance metrics, including ultra-low dark current density, excellent specific detectivity, and superior stability even under water, making them ideal for light communication. More importantly, this novel Se/Sb structure has been successfully extended to other chalcogenide semiconductor materials, showcasing significant potential for practical applications. [ABSTRACT FROM AUTHOR]

Selenium as one of the most historical semiconductors has been used for photovoltaics and photodetection, thanks to its excellent optoelectronic properties, superior stability, facile and low‐cost fabrication. However, commercialized Se‐based devices are mainly based on its amorphous state, which significantly limits the charge transport and requires relatively large bias voltage. The charge carrier dynamics of high‐performance crystalline Se thin films are barely reported, and related photodiodes have not been realized mainly limited by the large dark current and slow response speed. Here, poly‐crystalline Se thin films via vacuum evaporation, in situ thermal annealing, and engineered the interfaces with various metal electrodes are fabricated, which resulted in enhanced charge transport properties and reduced device leakage. The optimized Se photodiodes exhibited excellent performance metrics, including extremely low dark current density, decent specific detectivity, and superior stability. Furthermore, the optimized Se photodetectors are also introduced for single‐pixel imaging, which demonstrates excellent sensitivity and great potential for real applications. [ABSTRACT FROM AUTHOR]

Short‐wavelength infrared photo‐sensing materials are dominated by germanium, indium gallium arsenide, indium antimonide, and mercury cadmium telluride. However, the complex fabrication process and high production cost hinder their widespread applications. Recently, TexSe1‐x has shown great potential for infrared photodetection, but TexSe1‐x‐based devices are still suffering from extremely high dark current and poor device performance. In this work, high‐quality TexSe1‐x films are fabricated by thermal evaporation and low‐temperature annealing. The optoelectronic properties of the TexSe1‐x thin films are systematically investigated and optimized. The absorption spectrum is carefully tuned to cover the broad range from 300 to 1600 nm by modulating the ratio of Te and Se. Photodiodes based on the optimized TexSe1‐x thin films are also fabricated, and achieve high responsivity, reduced dark and low noise current density, and a fast response time of <850 ns. Then, prototypical devices based on Te0.65Se0.35 thin films are demonstrated for optical communications, indicating the great potential for next‐generation, low‐cost short‐wavelength infrared photodetection. [ABSTRACT FROM AUTHOR]

This paper presents a novel adaptive tracked robot equipped with passive swing arms for overcoming obstacles. First, the paper introduces the overall composition of the robot and focuses on the adaptive mechanism of the passive swing arms. Second, analyzing the single-step obstacle-overcoming process of the robot reveals the relationship between the obstacle height and the geometric parameters of the passive swing arms, establishing a kinematic model. Then, a dynamic model of the robot's obstacle-overcoming process is established by simplifying the robot into a crank–slider linkage, and the time range for the robot to overcome obstacles is analyzed. Finally, through virtual simulation and a physical prototype, the feasibility and maneuverability of the robot's design are verified. These findings demonstrate the potential of the robot in various applications, such as search and rescue missions and homeland security. [ABSTRACT FROM AUTHOR]

Benefiting from excellent optoelectronic properties and facile fabrication, Sb2Se3‐based semiconductor devices have drawn great attention in the last decade; in particular, Sb2Se3‐based solar cells and photodetectors have demonstrated decent performance metrics. However, the current research on Sb2Se3 devices is mainly focused on material and device processing and optimization, and few studies have been conducted on charge transport, which is limiting the further development of Sb2Se3‐based devices. To address this issue, post‐treatment techniques are introduced and their influence on the charge carrier dynamics of Sb2Se3 thin films is fully investigated. The charge carrier mobility of evaporated Sb2Se3 thin films is increased by an order of magnitude from 0.02 to 0.4 cm2 V−1 s−1 after the Se post‐treatment. Based on the optimized Sb2Se3 thin films, ultra‐fast photodiodes are further developed and a record‐fast response of 37 ns is achieved. Prototypical devices also demonstrated great potential for high‐speed photodetection in practical applications. [ABSTRACT FROM AUTHOR]

This paper deals with the construction of a novel family of multimode deployable mechanisms based on reconfigurable Bricard-like mechanisms. By connecting a number of identical threefold-symmetric (TFS) Bricard-like mechanisms, a multimode deployable arch is proposed for the first time, which can switch between the scissor-like deployable mode and the arch deformable mode through the transition configuration. Then new multimode center-driven deployable mechanisms can be obtained by connecting three and six multimode deployable arches. The obtained mechanism can switch between the scissor-like deployable mode and spherical deformable mode, and it can be reassembled by adjusting the number of TFS Bricard-like mechanisms to change its size. Finally, physical prototypes of the multimode deployable arch and multimode center-driven deployable mechanisms are fabricated and tested to validate the feasibility of the proposed approach and analysis. [ABSTRACT FROM AUTHOR]