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Photothermoelectric (PTE) detectors combine photothermal and thermoelectric conversion, surmounting material band gap restrictions and limitations related to matching light wavelengths, have been widely used in telecommunication band detection. Two-dimensional (2D) materials with gate-tunable Seebeck coefficient can induce the generation of photothermal currents under illumination by the asymmetric Seebeck coefficient, making them promising candidate for PTE detectors in the telecommunication band. In this work, we report that a newly explored van der Waals (vdW) layered material, SnP₂Se₆, possessing excellent field regulation capabilities and behaviors as an ideal candidate for PTE detector implementation. With the assistance of temperature-dependent Raman characterization, the suspended atomic thin SnP₂Se₆ nanosheets reveal thickness-dependent thermal conductivity of 1.4–5.7 W m⁻¹ K⁻¹ at room temperature. The 2D SnP₂Se₆ demonstrates high Seebeck coefficient (S) and power factor (PF), which are estimated to be −506 μV K⁻¹ and 207 μW m⁻¹ K⁻², respectively. By effectively modulating the SnP₂Se₆ localized carrier concentration, which in turn leads to inhomogeneous Seebeck coefficients, the designed dual-gate PTE detector with 2D SnP₂Se₆ channel demonstrates wide spectral photoresponse in telecommunication bands, yielding high responsivity (R = 1.2 mA W⁻¹) and detectivity (D* = 6 × 10⁹ Jones) under 1550 nm light illumination. Our findings provide a new material platform and device configuration for the telecommunication band detection.

Low-dimensional metal halide perovskites exhibit exceptional photoelectronic properties and intrinsic stability, positioning them as a promising class of semiconductor materials for light-emitting devices and photodetectors. In this work, we present a millimeter-scale single crystal of mixed low-dimensional (one-dimensional–zero-dimensional [1D–0D]) organic lead iodide with well-defined crystallinity. The fabricated single-crystal devices demonstrate high-sensitivity photoresponse and x-ray detection performance. By spatially isolating organic molecules to form the mixed 1D–0D crystal structure, ion migrations is effectively suppressed, resulting in a remarkable three orders of magnitude reduction in the dark current (56.4 pA @200 V) of the single-crystal devices. Furthermore, by enhancing the background characteristics, we achieved an impressive low x-ray detection limit of 154.5 nGys⁻¹ in the single-crystal device. These findings highlight that the mixed 1D–0D organic lead iodide configuration efficiently controls ion migration within the crystal structure, offering a promising avenue for realizing high-performance perovskite-based photodetectors and x-ray detectors.

Local phase transition in transition metal dichalcogenides (TMDCs) by lithium intercalation enables the fabrication of high-quality contact interfaces in two-dimensional (2D) electronic devices. However, controlling the intercalation of lithium is hitherto challenging in vertically stacked van der Waals heterostructures (vdWHs) due to the random diffusion of lithium ions in the hetero-interface, which hinders their application for contact engineering of 2D vdWHs devices. Herein, a strategy to restrict the lithium intercalation pathway in vdWHs is developed by using surface-permeation assisted intercalation while sealing all edges, based on which a high-performance edge-contact MoS₂ vdWHs floating-gate transistor is demonstrated. Our method avoids intercalation from edges that are prone to be random but intentionally promotes lithium intercalation from the top surface. The derived MoS₂ floating-gate transistor exhibits improved interface quality and significantly reduced subthreshold swing (SS) from >600 to 100 mV dec^–1. In addition, ultrafast program/erase performance together with well-distinguished 32 memory states are demonstrated, making it a promising candidate for low-power artificial synapses. The study on controlling the lithium intercalation pathways in 2D vdWHs offers a viable route toward high-performance 2D electronics for memory and neuromorphic computing purposes.

The relentless pursuit of sustainable and safe energy storage technologies has driven a departure from conventional lithium-based batteries toward other relevant alternatives. Among these, aqueous batteries have emerged as a promising candidate due to their inherent properties of being cost-effective, safe, environmentally friendly, and scalable. However, traditional aqueous systems have faced limitations stemming from water's narrow electrochemical stability window (~1.23 V), severely constraining their energy density and viability in high-demand applications. Recent advancements in decoupling aqueous batteries offer a novel solution to overcome this challenge by separating the anolyte and catholyte, thereby expanding the theoretical operational voltage window to over 3 V. One key component of this innovative system is the ion-selective membrane (ISM), acting as a barrier to prevent undesired crossover between electrolytes. This review provides a comprehensive overview of recent advancements in decoupling aqueous batteries, emphasizing the application of various types of ISMs. Moreover, we summarize different specially designed ISMs and their performance attributes. By addressing the current challenges ISMs face, the review outlines potential pathways for future enhancement and development of aqueous decoupling batteries.

Due to the built-in electric field induced by spontaneous polarization in hybrid perovskite (HP) ferroelectrics, the devices based on them exhibit excellent performance in self-powered photodetection. However, most of the self-powered photodetector are made of lead-based HP ferroelectrics and have a relatively narrow photoresponse waveband. Although lead-free HPs solve the problem of lead toxicity, their optoelectronic performance is inferior to that of lead-based HPs and photoresponse waveband is limited by its optical band gap, which hinders their further application. To solve this problem, herein, a lead-free HP ferroelectric (HDA)BiI₅ (HDA is hexane-1,6-diammonium) with large spontaneous polarization shows an enhanced photocurrent and achieves x-ray-ultraviolet–visible-near-infrared (x-ray-UV–Vis–NIR) photoresponse through the ferro-pyro-phototronic (FPP) effect. The ferroelectric, pyroelectric, and photovoltaic characteristics coupled together in a single-phase (HDA)BiI₅ ferroelectric is an effective way to improve the performance of the devices. What is particularly attractive is that the FPP effect not only improves the optoelectronic performance of (HDA)BiI₅, but also achieves broadband photoresponses beyond its optical absorption range. Especially, the current boosting with an exceptional contrast of ~1100% and 2400% under 520 and 637 nm, respectively, which is associated with FPP effect. Meanwhile, single crystal self-powered photodetector based on (HDA)BiI₅ also exhibit significant FPP effects even under high-energy x-ray, which owns an outstanding sensitivity of 170.7 μC Gy⁻¹ cm⁻² and a lower detection limit of 266 nGy s⁻¹ at 0 V bias. Therefore, it is of great significance to study the coupling of multiple physical effects and improve device performance based on lead-free HP ferroelectrics.

Crystallization speed of phase change material is one of the main obstacles for the application of phase change memory (PCM) as storage class memory in computing systems, which requires the combination of nonvolatility with ultra-fast operation speed in nanoseconds. Here, we propose a novel approach to speed up crystallization process of the only commercial phase change chalcogenide Ge₂Sb₂Te₅ (GST). By employing TiO₂ as the dielectric layer in phase change device, operation speed of 650 ps has been achieved, which is the fastest among existing representative PCM, and is comparable to the programing speed of commercial dynamic random access memory (DRAM). Because of its octahedral atomic configuration, TiO₂ can provide nucleation interfaces for GST, thus facilitating the crystal growth at the determinate interface area. Ti–O–Ti–O four-fold rings on the (110) plane of tetragonal TiO₂ is critical for the fast-atomic rearrangement in the amorphous matrix of GST that enables ultra-fast operation speed. The significant improvement of operation speed in PCM through incorporating standard dielectric material TiO₂ in DRAM paves the way for the application of phase change memory in high performance cache-type data storage.

Flexible perovskite photodetectors (FPDs) are promising for novel wearable devices in bionics, robotics and health care. However, their performance degradation and instability during operations remain a grand challenge. Superior flexibility and spontaneous functional repair of devices without the need for any external drive or intervention are ideal goals for FPDs. Herein, by using phenyl disulfide instead of alkyl disulfide as a crosslinking agent, disulfide bonds with lower bond energy are introduced, thus endowing the polyurethane network (SCPU) with the ability of self-healing at room temperature. SCPU is filled to the grain boundary of perovskite film, which not only improves the crystal quality of perovskite and mechanical stability of FPD but also enables FPD to self-heal at room temperature. As a result, the as-prepared FPD exhibits a superior responsivity of 0.4 A W⁻¹, a high specific detectivity of 2.5 × 10¹¹ Jones and 2 μs fast response time in a self-powered mode. More importantly, the FPD still retained 91% of the initial photo responsivity after 9000 times of bending upon cyclic healing. This polymer doping strategy provides an effective solution for stable operation and room-temperature self-healing for FPDs.

The demand for high-performance X-ray detectors leads to material innovation for efficient photoelectric conversion and carrier transfer. However, current X-ray detectors are often susceptible to chemical and irradiation instability, complex fabrication processes, hazardous components, and difficult compatibility. Here, we investigate a two-dimensional (2D) material with a relatively low atomic number, Ti₃C₂T_x MXenes, and single crystal silicon for X-ray detection and single-pixel imaging (SPI). We fabricate a Ti₃C₂T_x MXene/Si X-ray detector demonstrating remarkable optoelectronic performance. This detector exhibits a sensitivity of 1.2 × 10⁷ μC Gy_air⁻¹ cm⁻², a fast response speed with a rise time of 31 μs, and an incredibly low detection limit of 2.85 nGy_air s⁻¹. These superior performances are attributed to the unique charge coupling behavior under X-ray irradiation via intrinsic polaron formation. The device remains stable even after 50 continuous hours of high-dose X-ray irradiation. Our device fabrication process is compatible with silicon-based semiconductor technology. Our work suggests new directions for eco-friendly X-ray detectors and low-radiation imaging system.

The electrolyte-wettability at electrode material/electrolyte interface is a critical factor that governs the fundamental mechanisms of electrochemical reaction efficiency and kinetics of electrode materials in practical electrochemical energy storage. Therefore, the design and construction of electrode material surfaces with improved electrolyte-wettability has been demonstrated to be important to optimize electrochemical energy storage performance of electrode material. Here, we comprehensively summarize advanced strategies and key progresses in surface chemical modification for enhancing electrolyte-wettability of electrode materials, including polar atom doping by post treatment, introducing functional groups, grafting molecular brushes, and surface coating by in situ reaction. Specifically, the basic principles, characteristics, and challenges of these surface chemical strategies for improving electrolyte-wettability of electrode materials are discussed in detail. Finally, the potential research directions regarding the surface chemical strategies and advanced characterization techniques for electrolyte-wettability in the future are provided. This review not only insights into the surface chemical strategies for improving electrolyte-wettability of electrode materials, but also provides strategic guidance for the electrolyte-wettability modification and optimization of electrode materials in pursuing high-performance electrochemical energy storage devices.