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Thin film lithium niobate is one of the most crucial platforms in the next generation of integrated optoelectronics because of its ability to integrate tight optical confinement, low optical loss, and active optical functions. A current challenge in the field of thin film lithium niobate photonics is the development of high‐performance photodetectors to achieve multifunctional photonic integrated circuits. This study introduces a high‐performance MoTe2 photodetector integrated on a thin film lithium niobate waveguide. The photodetector achieves the lowest dark current and highest on/off ratio among waveguide‐integrated photodetectors on a thin film lithium niobate platform. Due to a slight asymmetry in the behavior of the two electrode contacts of the device, the photodetector also achieves self‐driven. At zero bias and a wavelength of 1310 nm, a dark current of ≈20 pA, and an on/off ratio exceeding 105 are achieved. At a bias voltage of 1 V, the measured dark current, responsivity, and on/off ratio are 1.13 nA, 309 mA/W, and 1.8 × 104, respectively. Notably, the device exhibits fast rise and fall times of 9.3 and 13.5 µs, respectively, accompanied by a high detectivity of 2.58 × 1011 W−1. [ABSTRACT FROM AUTHOR]

Harnessing energy from underwater bubbles has garnered significant attention, particularly for powering off‐grid circuitry. However, the efficiency of bubble‐driven liquid‐solid interface charge transfer remains low. This research unveils a phenomenon: accelerated bubble slippage enhances liquid‐solid interfacial charge transfer. Building upon this discovery, a pulse bubble‐based power generation technique is proposed, achieving an energy density of 24.2 mJ L−1 generated by pulsed bubbles. The crux of pulse bubble power generation lies in the precise control of impact velocity. By meticulously regulating the impact kinetic energy of bubbles, the accumulated potential energy of multiple small bubbles is converted into instantaneous pulse kinetic energy. A typical pulse bubble is controlled within a 72 ms timeframe, unleashing a surge of energy that can directly illuminate 400 light‐emitting diodes. This approach represents a groundbreaking advancement in underwater energy harvesting technology, dramatically expanding its potential applications. [ABSTRACT FROM AUTHOR]

Flexible piezoelectric energy harvesters (FPEHs) have wide applications in mechanical energy harvesting, portable device driving, and piezoelectric sensors. However, the poor output performance of piezoelectric energy harvesters and the intrinsic shortcoming of piezoelectric sensors that can only detect dynamic pressure limit their further applications. BaTiO3 (BT) and PVDF are deposited on the glass fiber electronic cloth (GFEC) by impregnation and spin‐coating methods, respectively, to form BT‐GFEC/PVDF piezoelectric composite films. A mixed solution of mechanoluminescence (ML) particles ZnS:Cu and PDMS are used as the encapsulation layer to construct a high‐performance ML‐FPEH with self‐powered electrical and optical dual‐mode response characteristics. Due to the interconnection structure of the piezoelectric films, the prepared ML‐FPEH illustrates a high effective energy harvesting performance (≈58 V, ≈43.56 µW cm−2). It can also effectively harvest mechanical energy from human activities. More importantly, ML‐FPEH can sense stress distribution of hand‐writing via ML to achieve stress visualization, making up for the shortcomings of piezoelectric sensors. This work provides a new strategy for endowing FPEH with dual‐mode sensing and energy harvesting. [ABSTRACT FROM AUTHOR]

Antibiotic residues have become a significant challenge in food safety, threatening both ecosystem integrity and human health. To combat this problem, we developed an innovative photo‐powered, self‐powered aptasensor that employs a novel carbon‐doped three‐dimensional graphitic carbon nitride (3D‐CN) combined with a metal‐organic framework composed of N‐doped copper(I) oxide‐carbon (Cu2O@C) skeletons. The 3D‐CN serves as the photoanode, offering stable photocurrent production due to its three‐dimensional open framework structure. The N‐doped Cu2O@C acts as the photocathode, providing oxidation protection for the metal core and enhancing light absorption due to its metal‐organic framework structure. A key feature of our work is exploiting the Fermi level difference between the n‐type photoanode and p‐type photocathode, which facilitates faster migration of photogenerated electrons toward the photocathode, thereby enhancing the sensor's self‐powered effect. Experimental results reveal that upon aptamer loading, the sensor can linearly detect tetracycline (TC) within a range of 0.5 pmol/L to 300 nmol/L, with a detection limit as low as 0.13 pmol/L. It also demonstrates excellent selectivity, stability, and reproducibility, making it applicable to real samples such as milk and river water. Consequently, our research provides a highly efficient and sensitive method for monitoring TC in food, with significant practical implications and profound impacts on food safety. [ABSTRACT FROM AUTHOR]

Conventional research on linear polarization photodetector for 2D materials has focused on the search for different anisotropic materials, combinations between materials, introducing plasmonic structures, and patterning 2D materials to improve performance. However, these methods provide limited improvement in polarization sensitivity. Here, a balanced photodetector structure is proposed that does not require an additional process and relies only on the presence of anisotropy in the material itself to substantially improve the polarization sensitivity. The balanced photodetector consists of two ReS2 photodetectors, where the single ReS2 photodetector exhibits excellent performance at 650 nm illumination, including a responsivity and detectivity of 0.28 A W−1 and 4.22 × 109 Jones. Benefiting from the anisotropy of ReS2, the single photodetector achieves excellent polarization sensitivity of 2.79 at 650 nm. The balanced photodetector system achieves an excellent performance of ≈20 dB linear polarization extinction ratio and 0.003° Hz−1/2 noise equivalent light polarization difference at 100 kHz. These performances can also be further optimized by adjusting the gate voltage. The results provide a basis for further development of high‐performance polarization photodetector for 2D materials. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have aroused worldwide efforts for developing optoelectronic devices due to their unique optical properties and low‐cost simple fabrication process. In recent years, various perovskites‐based miniaturized optical devices have been actively investigated due to their record‐breaking efficiency in different fields, including environmental monitoring, remote sensing, biomedical imaging, and optical communications. In this review, a succinct and critical survey of recently discovered organic–inorganic perovskite photodetectors providing insights into their structural properties and key performance parameters is staged. First, key features of perovskites‐based photodetectors emphasizing their optoelectronic and electrical properties are introduced. Then, the polarization‐sensitive detection of metal halide perovskites using polarization‐selective optical structures is discussed. The bandgap engineering for tailoring the properties of perovskite photodetectors by changing the chemical composition and material structures is also highlighted in this report. Finally, a perspective on future opportunities and current challenges for designing perovskite‐based optoelectronic devices is presented. [ABSTRACT FROM AUTHOR]

The growing power demands of wearable electronic devices have stimulated the development of self‐powered systems in noninvasive healthcare. Herein, ultrathin homogeneous 2D flower‐like nickel–cobalt layered double hydroxide (Ni–Co LDH) nanocomposites are prepared by a one‐step hydrothermal method to integrate a self‐powered system for wearable sweat copper ions (Cu2+) monitoring. The Ni–Co LDH nanocomposites with a lamellar structure and numerous active sites, exhibit sensitive selectivity and low detection limits for Cu2+. In addition, the optimized Ni–Co LDH provides favorable capacitive characteristics as supercapacitors for self‐powering sensors, ensuring continuous sensing energy sources. By connecting wirelessly to a smart device, a self‐powered system is constructed to achieve wearable sensing of Cu2+ in the practical application of sweat. This simple yet effective strategy provides new opportunities for the development of self‐powering health monitoring sensors, as well as smartsensing more heavy metals. [ABSTRACT FROM AUTHOR]

Wearable electronics with multi‐functionalities are widely utilized in various domains, including everyday living, healthcare, military training, and sports. Advances in flexible electronic technology, new materials, artificial intelligence technology, and sensor technology have accelerated the rapid development of smart wearable devices toward multifunctional and highly integrated trends. The energy supply technology based on the human‐body energy harvesting method endows wearable, multifunctional electronic devices with sustainable, renewable, and self‐powered characteristics, which proposes a solution strategy for the function expansion and energy supply of wearable devices. Herein, this paper discusses recent research on various methods of harvesting human body energy and wearing parts respectively, focusing on the new materials, structures, and processes involved in the representative studies, as well as the impact on energy harvesting and output, and functional applications. Furthermore, the challenges and obstacles faced in the creation of wearable multifunctional devices based on human self‐sufficiency and propose solution strategies to propel them in order to advance the creation of the next wave of intelligent wearable technology are also discussed. [ABSTRACT FROM AUTHOR]

Polarization‐sensitive photodetectors have garnered significant interest due to their promising applications in navigation, remote sensing, and optical communication. However, conventional polarized light detectors relying on optical filters face challenges due to intricate fabrication and calibration procedures. While structures based on in‐plane anisotropic 2D materials have the potential to offer viable solutions for polarization detection, achieving both low power consumption and high performance remains challenging. Herein, a self‐powered anisotropic/isotropic ReS2/SnSe2 van der Waals (vdWs) heterojunction detector with high‐performance features is constructed. This device exhibits outstanding photovoltaic (PV) performance across a wide spectral range from 405 to 850 nm without bias, featuring excellent responsivity (0.966 A W−1) and specific detectivity (1.47 × 1010 Jones) under 650 nm laser illumination. Moreover, benefiting from the built‐in electric field that promotes carrier separation and extremely low dark current, the device shows fast response time (230/240 µs) with an on/off ratio of up to 104. Furthermore, the ReS2/SnSe2 photodetector demonstrates exceptional polarization encoding performance, with a polarization ratio of 1.56 under 650 nm illumination, opening up new possibilities in optical communication technology development. This research provides a novel and viable option for developing energy‐efficient and high‐performance polarization‐sensitive detectors. [ABSTRACT FROM AUTHOR]

Heterojunctions formed between undoped and Eu‐doped NiO nanofibers (NFs) and n‐Si were fabricated by electrospinning the NiO:Eu NFs onto Si. Since the photoresponse of the Eu‐doped NiO‐containing device was better than the undoped one, the study focused on the doped NiO‐containing device. This was explained by the increase in electron kinetics in terms of the active role of Eu in bonding with the 4f orbitals and the s, d, and f states of NiO. Electro‐optical measurements of the NiO:Eu NFs/n‐Si heterojunction were performed in the visible region depending on the light intensity and in the UV and NIR regions for 10 mW/cm2 powers. It was observed that the device exhibits a good level of rectification properties and responds very well to all lights. At all three light sources, the heterojunction photodetector exhibited self‐powered behavior. Furthermore, for 10 mW/cm2 light intensity, the NiO:Eu NFs/n‐Si photodetector achieved R values of 1.84 A/W at 365 nm, 0.98 A/W at 395 nm, and 1.54 A/W at 850 nm, while it is 0.12 A/W for visible light. Besides, the device showed an external quantum efficiency of 625% and this was attributed to the photocurrent gain. In self‐driven mode, D* values have been determined as 3.0 × 1012 Jones, 2.6 × 1012 Jones, and 2.9 × 1012 Jones for 365, 395, and 850 nm, respectively. The performance of NiO under UV light was attributed to the absorption of NiO under UV light, as well as the very good excitation of (Eu3+) ions by UV light. [ABSTRACT FROM AUTHOR]

Conventional research on linear polarization photodetector for 2D materials has focused on the search for different anisotropic materials, combinations between materials, introducing plasmonic structures, and patterning 2D materials to improve performance. However, these methods provide limited improvement in polarization sensitivity. Here, a balanced photodetector structure is proposed that does not require an additional process and relies only on the presence of anisotropy in the material itself to substantially improve the polarization sensitivity. The balanced photodetector consists of two ReS2 photodetectors, where the single ReS2 photodetector exhibits excellent performance at 650 nm illumination, including a responsivity and detectivity of 0.28 A W−1 and 4.22 × 109 Jones. Benefiting from the anisotropy of ReS2, the single photodetector achieves excellent polarization sensitivity of 2.79 at 650 nm. The balanced photodetector system achieves an excellent performance of ≈20 dB linear polarization extinction ratio and 0.003° Hz−1/2 noise equivalent light polarization difference at 100 kHz. These performances can also be further optimized by adjusting the gate voltage. The results provide a basis for further development of high‐performance polarization photodetector for 2D materials. [ABSTRACT FROM AUTHOR]

The ocean harbors an abundance of resources, encompassing not only wave energy but also considerable wind energy. Triboelectric nanogenerator (TENG), as a technology for harvesting low‐frequency, high‐entropy mechanical energy, has shown distinct advantages in the collection and application of marine and wind energy. This study introduces a triboelectric Wind and wave energy harvester (TWWEH), an energy collector based on TENG, which can be used to harness wind and wave energy. The TWWEHs comprise a wind‐driven TENG (W‐TENG) for wind energy collection and a ring‐shaped TENG (R‐TENG) for wave energy collection. The proposed vertically integrated TENG architecture enhances spatial utilization rate. Under oscillatory conditions of 0.8 Hz and ±30°, the R‐TENG generates a peak power of 0.20 mW. While at a wind speed of 10 m s−1, a peak power of the W‐TENG can reach 0.11 mW. This research provides a promising solution to harvest wave and wind energy from the ocean, offering significant potential applications in establishing self‐powered oceanic assessment and meteorological systems. [ABSTRACT FROM AUTHOR]

The moisture‐enabled electricity generators (MEGs) represent an appealing clean power strategy within the realm of hydrovoltaic technology. However, their stable operation under all‐weather conditions is still challengeable due to the effect of ambient humidity. Herein, a self‐water‐storage MEGs with multifunctionality was developed. Gel textiles are employed as the proton‐release layer, while graphite fibers loaded with tin‐bismuth alloy liquid metal serve as water‐storing electrode. The gel textiles absorb water permeating down from the electrodes, releasing protons, which then react with the active electrode to enhance output performance. The experiment demonstrates that a device can generate a voltage of 0.55 V and a current of 7.08 μA after water storage, with a maximum power density of 1.14 μW·cm‐². The device's performance output can remain stable within a wide temperature range. The experiment confirms that the electrical output of the device originates from ionic diffusion, while density functional theory (DFT) and molecular dynamics (MD) calculations reveal the importance of the strong hydrolysis ability of the polymer and the high adsorption energy of the liquid metal for H3O+ on the output performance of the device. Furthermore, the integrated device has demonstrated effective applications in driving microelectronic devices, charging capacitors and, self‐powered health monitoring. [ABSTRACT FROM AUTHOR]

In the search for new advanced 2D materials for technological applications and to expand the research of non‐van der Waals (non‐vdW) 2D electronic devices, this study presents a novel strategy for liquid phase exfoliation (LPE) of non‐vdW Cr2S3 to produce Cr2S3 nanosheets (NSs). By utilizing N‐methyl‐2‐pyrrolidone (NMP), bulk Cr2S3 is separated along the (001) plane, resulting in the formation of NSs with an average thickness of ≈3 nm. Various characterization techniques are applied to the Cr2S3 material before and after LPE. Subsequently, the obtained Cr2S3 NSs are integrated into a photoelectrochemical (PEC)‐type photodetector (PD) to evaluate the photoelectric conversion efficiency under varying conditions. The findings indicate that the developed PD exhibits a distinct self‐powered photodetection capability with a photocurrent (Pph) of 39.5 nA cm−2, a photoresponsivity (Rph) of 622 nA W−1, and a detectivity (D*) of 0.5 × 107 Jones under 350 nm irradiation at 0 V. Moreover, the PD demonstrates rapid response time (0.06 s) and good long‐term stability (over 15 days), thus providing valuable insight for the advancement of non‐vdW Cr2S3‐based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Piezoionics, a new frontier that employs mobile ions as energy and charge carriers, plays an important role in new energy and intelligent electronics. However, a significant challenge consists in balancing the structural design of metal ions coordination hydrogel (HG‐MI) piezoionics for current conduction, voltage generation, and especially mechanical adaptability. Herein, inspired by the spider webs' unique structure, a strategy by realizing the full potential of metal‐ligand ions ([(OH)Cl2]3−) to facilitate the keggin‐type structure AlOHAlOH generation together with activate functional carboxyls is introduced. Impressively, the whole property of the product HG‐AlPAC, especially the mechanical performance is improved. For example, the toughness of HG‐AlPAC is 2.75 MJ m−3, more than twofold that of traditional HG‐AlAS/AC/AN samples. Due to the stable fixation of ─Al─OH─ thus promoting Cl− separation upon external force, HG‐AlPAC achieves a piezoionic coefficient of 0.89 mV KPa−1 and energy conversion efficiency of 1.29%, promising for mechanical‐electrical conversion and sensing. Combined with the good mechanical performance with the excellent piezoionic properties, underscores its potential as a tactile nerve system of analgesia patients to prevent them from being injured. This work intends to provide a stride toward mechanically robust self‐powered piezoionic sensors and offer insights into ionotropic materials for energy harvesting, human‐machine interaction, and biointerface. [ABSTRACT FROM AUTHOR]

Graphene electrodes draw considerable attention in solar‐blind ultraviolet (SBUV) detection owing to their unique features including high ultraviolet (UV) transparency and superior intrinsic carrier mobilities. However, their adoption comes with challenges, as the most commonly used preparation technique, i.e., the dry transfer process, is challenging to achieve mass production. In this work, graphene/β‐Ga2O3 heterojunction photodetectors processed by wet transfer are reported. Benefiting from the UV‐transparent electrode and heterojunction, both the responsivity and response speed are improved. The characteristic of the graphene/β‐Ga2O3 interface is analyzed by the current–voltage (I–V) and capacitance–voltage (C–V) curves, featuring a high‐quality junction. Operated at zero bias, the photodetector exhibits a low dark current of less than 1 pA and a high response speed of less than 1 ms. An excellent UV‐C/visible rejection ratio is also achieved. Importantly, the photodetector performs excellent reproducibility and performance stability. This results provide a new perspective for the mass production of graphene/Ga2O3 integrated devices, enabling high‐performance Ga2O3 photodetector arrays. [ABSTRACT FROM AUTHOR]

Self‐powered photodetection devices, which meet the requirement of environmental sustainability, are widely designed by PN heterojunctions. The design of the semiconductor/metal interface is vital in PN‐junction devices. In particular, the elevated potential barrier at the metal/semiconductor interface impedes efficient carrier transport. Therefore, optimizing the semiconductor/metal interface for the PN junction, either by reducing the interface barrier or leveraging the built‐in electric field within the Schottky junction, holds significant importance in enhancing the performance of PN‐junction devices. In this study, an InSe/MoTe2 Type‐II PN heterojunction photodetector is constructed, with graphene (Gr) and gold (Au) serving as electrodes in contact with InSe and MoTe2, respectively. Benefiting from the reduced barrier in Au/InSe interfaces and the built‐in electric field formed at the InSe/MoTe2 and MoTe2/Au interfaces in the same direction, the device achieves an ultra‐fast photoresponse speed of 14 µs and an ultra‐low dark current of 8.5 × 10⁻¹⁴ A at zero bias. Furthermore, the device exhibits a remarkable light on/off ratio up to 105 and achieves broad‐spectrum photodetection ranging from the visible to infrared wavelength. This research highlights the enormous potential of the Gr/InSe/MoTe2 van der Waals heterostructure in the realms of self‐powered photodetection, imaging, and optical communication. [ABSTRACT FROM AUTHOR]

Van der Waals heterostructures (vdWHs) consisting of 2D materials offer a practical and effective approach for engineering multifunctional, high‐performance photodetectors. However, 2D vdWHs photodetectors based on photoconductive effects require an external power input and are often accompanied by a large dark current, which hinders the development of miniaturization and portability of devices and greatly limits the application of devices in complex environments. Herein, a self‐powered photodetector constructed from an InSe/PtS2 vdWH with an extremely low dark current (≈10−14 A) at zero bias and a large rectification ratio of 5.1 × 103 is reported. Leveraging the robust built‐in electric field of the InSe/PtS2 vdWH, the device demonstrates pronounced photovoltaic effects, characterized by an open‐circuit voltage of 0.395 V and a substantial short‐circuit current of 37.1 nA. Remarkably, a high responsivity and detectivity of 211 mA W−1 and 8.58 × 1012 Jones, an excellent light on/off ratio of 0.8 × 107 , and a fast response time of 465/470 µs are achieved, at zero bias. The device showcases a broadband self‐powered photoresponse spanning from 265 to 1064 nm. This study demonstrates the high potential of the InSe/PtS2 vdWH for broadband self‐powered photodetector applications. [ABSTRACT FROM AUTHOR]

Ascribing to the low power consumption, self‐powered photodetectors (SPPDs) have promising applications in optical communication and photoelectric imaging. Aiming to improve the performance of SPPDs, many efforts have been devoted to exploring the semiconductor‐heterojunction candidates. However, key parameters of SPPDs, especially the responsivity and response time, still lag behind those of the standard photodetectors. Here, with the modification of the transport behavior, ultra‐high‐performance SPPDs are fabricated based on the reported Sb2Se3/ZnO heterojunction. Keeping the broadband detection from infrared to UV region, the SPPDs achieve increased responsivity and detectivity of 0.38 A W−1 and 1.40 × 1013 Jones, respectively. Especially, according to the cut‐off frequency measurements, the response time is improved to 93.5/75.0 ns, which is in a microsecond, even millisecond level for most of the current SPPDs. These studies further reveal the mechanism of the performance modification and indicate that this method can be applied to fabricate imaging arrays. With the combination of the experimental results, we provide an effective method for enhancing the performance of SPPDs toward their applications. [ABSTRACT FROM AUTHOR]

Self‐powered near‐infrared (NIR) photodetectors utilizing low‐dimensional materials are promising owing to their low‐power‐consumption and superior photoresponse performance. The strong light‐matter interaction and other intriguing physical mechanisms (such as high mobility, dangling‐bond‐free surface) in 2D semiconductor materials, combined with the flexible fabrication of device structures, create new opportunities for the optoelectronic devices. Here, a self‐powered NIR Schottky junction photodetector is demonstrated by vertically stacking 2D PtSe2 film atop an InP wafer. The strong built‐in electric field formed at PtSe2/InP interface endows the device with self‐powered operation with an ultralow dark current of 45 pA at room temperature under 0 V bias. The responsivity and detectivity at 940 nm illumination reach up to 0.718 A W−1 and 4.37 × 1012 Jones, respectively. Furthermore, TCAD simulations showed that the significant electric field at the PtSe2/InP interface is pivotal for its superior self‐powered detection performance. Remarkably, the device achieves a high Ilight/Idark ratio exceeding 105 and a fast response time of 4.35/5.66 µs, and sensitivity to NIR light polarization. This study provides a new perspective for the integration of hybrid 2D materials with 3D semiconductors in the next‐generation optoelectronic devices and integrated systems. [ABSTRACT FROM AUTHOR]

Heterojunction phototransistor (HPT) is considered the most promising detector technology in weak ultraviolet (UV) signal detection due to its inherent internal gain through transistor action. However, achieving high‐performance self‐powered UV HPTs remains a significant challenge. In this study, a high‐performance self‐powered p+‐GaN/n−‐ZnO/Au UV HPT with ZnO serving as the floating base is cleverly designed. The device features a unique back‐to‐back configuration of the p+‐GaN/n−‐ZnO heterojunction and n−‐ZnO/Au Schottky junction, along with an ultrathin ZnO base layer of a 3D nanowire network structure. This design enables the fabricated p+‐GaN/n−‐ZnO/Au UV HPT to operate in a self‐powered mode with exceptional performance metrics. Under zero bias, the device exhibits outstanding characteristics including ultralow dark current of 1.7 × 10−13 A, remarkable Iphoto/Idark ratio of 106, fast response speed (tr = 150 µs / tf = 250 µs), high responsivity of 9.74 A W−1, and detectivity of 1.58 × 1014 Jones, representing the best result achieved for UV HPTs thus far at zero bias. Moreover, the fabricated UV HPT is successfully demonstrated in solar‐blind imaging and UV communication systems without the need for an external power supply. This work presents effective and practical design strategies for achieving high‐performance self‐powered UV HPTs. [ABSTRACT FROM AUTHOR]

In the swiftly progressing landscape of wearable electronics and the Internet of Things (IoTs), there is a burgeoning demand for devices that are lightweight, cost‐effective, and self‐powered. In this study, a self‐powered bidirectional knee joint motion monitoring system is introduced, leveraging a dual ratchet sensing (DRS) system fabricated using 3D printing technology. This approach offers substantial economic and portability benefits. The DRS system is engineered to harness the negative work generated from knee joint movements to power commercial electronic devices, obviating the need for additional metabolic energy from the human body. By synergizing the DRS with virtual reality technology, it becomes feasible to monitor knee joint movements in real‐time with remarkable accuracy, presenting a novel avenue for the integration of digital twin technology. Through the amalgamation of convolutional neural network machine learning algorithms with Bayesian optimization techniques, the DRS system can discern up to 97% of knee joint movements, paving the way for innovative applications in smart rehabilitation and healthcare. [ABSTRACT FROM AUTHOR]

Underwater optical communication (UOC) based on the novel photoelectrochemical (PEC) type photodetector has garnered substantial interest in the field of marine resource exploration and ocean investigation due to its strong operability, self‐powered capability, and large sensitive area in harsh underwater environments. To achieve high sensitivity, fast transmission speed, and broadband response characteristics, vertical‐GaS nanosheets‐based PEC photodetectors are prepared by chemical vapor deposition for UOC application. The GaS based PEC photodetector exhibits excellent self‐powered photodetection and a broad UV–vis photoresponse range as well as high stability performance in both Na2SO4 electrolyte and seawater. Notably, it also demonstrates an exceptional photoresponsivity of 11 mA W−1 coupled with a fast response and recovery time of 12.9 and 13 µs which are superior to those of 2D layered materials and conventional wide‐bandgap semiconductors. These improvements are mainly due to the large surface area, short diffusion length, as well as high carrier mobility of vertically‐oriented GaS nanosheets. Strikingly, the constructed GaS photodetector showcases a broad bandwidth exceeding the −3 dB cutoff frequency of 55.3 kHz during UOC testing, successfully enabling transmission and decoding of character information. This work establishes the groundwork for developing high‐performance, self‐powered UV–vis photodetectors adaptable to UOC using PEC technology. [ABSTRACT FROM AUTHOR]

Myoelectric prosthetic hands and fingers with grasping functions have challenges such as weight, cost, and grasping performance of flexible objects owing to the use of electric actuators. To resolve these problems, we propose a self-powered movable prosthetic finger using pneumatic pressure. This prosthetic finger utilizes the flexion/extension of the remaining finger of the user to drive a wire and flex or extend the finger joints. The use of a tendon (wire) and belt drives reduces the space occupied by the prosthetic finger unit compared with conventional linked prosthetic fingers. Furthermore, a sealed-air bellows is used for the joint for flexible grasping owing to passive variable-compliance and damping, which is impossible with only a tendon drive. These features have resulted in the stable grasping of various objects that are difficult to grasp using prosthetic fingers based on conventional technologies. [ABSTRACT FROM AUTHOR]

Artificial visual memory systems have been of particular interest since the development of machine vision and bionic robots. Ordinarily, the conventional system architecture requires the complex integration of two functional modules, a photo‐sensor and a memory device, which greatly limits the operating efficiency and increases the extra energy consumption. Nonetheless, other simply configured optoelectronics memory devices generally face challenges of adaption in complex light environments. Here, a resistive switching (RS) perovskite‐based photomemristor is presented that mimics the retina function. The dual function of light perception and in situ storage are both achieved. In the dark condition, it exhibits impressive memory performance with a high ON/OFF ratio of 104, a long retention time of over 104 s, and a low operating voltage of 0.38 V. With illumination, it shows self‐powered, broadband photo‐detecting characteristics with responsivity of 70 mA W−1 and detectivity of 7.5 × 1010 Jones. More importantly, benefiting from the material dual‐phase configuration, the highly steady photo‐adjusted RS windows are achieved. Its light‐adaptive memory application in dynamic environments is further demonstrated using the mimicking retina for a machine eye. This work can provide a strategy for enhanced RS photomemristor and its application in changing and varied scenarios. [ABSTRACT FROM AUTHOR]

Electric signal accelerates full‐thickness wound healing in the clinic, which is usually generated by a large power generation system and requires delicate control by authorized personnel. Here, a self‐powered flexible and biocompatible thermoelectric device with exceptionally high power generation efficiency is developed. It generates 10 mV voltage at a temperature gradient of 10 K, outperforming all reported flexible thermoelectric devices. Accordingly, it can directly and efficiently convert the omnipresent heat in the skin to electricity at the microvolt level. The output electricity activates and upregulates the expression of Piezo1‐mediated pathways that are associated with tissue regeneration, accelerating the cell migration and proliferation in vitro and healing the wound 4 days faster in vivo. Importantly, the thermoelectric device fast‐heals the wound without involving any additional electric circuit such as an amplifier. These advantages will revolutionize the designing of self‐powered wearable bioelectronics for diagnosing, monitoring, and treating various pathological conditions employing the skin heat. [ABSTRACT FROM AUTHOR]

A self-powered bimodal tactile imaging device (TID) is developed for ultrasensitive pressure sensing, real-time visualization recognition, and precise touch positioning. Furthermore, based on optical-electrical bimodal tactile imaging of the TID, an intelligent control has been achieved through synergetic effect of visualization recognition and precise touch positioning. [Display omitted] • A self-powered bimodal tactile imaging device is developed for visible ultralow-pressure sensing and touch positioning. • By embedding high dielectric BTO:La NPs into PVDF-HFP matrix, the TIEL properties are greatly enhanced. • The TIEL is developed for visible tactile imaging and real-time visualization recognition under the aid of machine learning. • An intelligent control system based on the bimodal optical and electrical signals of the TID is established. In the domain of smart robotics, the refinement of tactile imaging constitutes a seminal element for enhancement of human–machine interaction (HMI) and enrichment of artificial intelligence (AI). This field is confronted with dual challenges of achieving high-sensitive pressure detection and precise localization of tactile stimuli. In response, the current research introduces a groundbreaking self-powered bimodal tactile imaging device (TID), featuring a configuration of high-dielectric thin film superimposed on laser-induced graphene (LIG) electrodes. This pioneering design is conceived to facilitate not only the detection of subtle pressure but also to support real-time visual recognition and intelligent control functionalities. The bimodal nature of the TID allows for the transformation of slight tactile inputs into both luminous triboelectrification-induced electroluminescence (TIEL) and measurable electrical signals, thereby seamlessly merging the realms of tactile perception and optical display. Leveraging the luminosity of TIEL, the TID adeptly achieves tactile imaging and immediate visual recognition, with its capabilities further enhanced through the integration of machine learning algorithms. Additionally, the TID exhibits a remarkable proficiency in precise tactile localization, through the analysis of voltage outputs initiated by delicate touching and sliding motions. Moreover, an advanced intelligent control system, predicated on the optical-electrical dual-modal sensing provided by the TID, has been developed. This system illustrates the synergistic fusion of visual recognition with accurate tactile localization, underscoring the substantial utility of the bimodal TID across diverse applications in HMI, AI, and intelligent robotic platforms and heralding new avenues for interactive and responsive robotic systems. [ABSTRACT FROM AUTHOR]

The burgeoning field of soft bioelectronics heralds a new dawn in medical treatment for neurological and psychiatric conditions, presenting innovative methods for the stimulation, inhibition, and precise sensing of neuronal activities. Central to these advancements is the challenge of power supply; devices dependent on traditional batteries face limitations regarding miniaturization and require invasive surgeries for battery replacement. Triboelectric nanogenerators (TENGs), which generate power from biomechanical movements, offer a promising solution for developing self-powered neurostimulation devices without the need for an external power supply. This review delves into recent progress in TENGs, with a focus on their application in self-powered neurostimulation systems. The utility of TENGs across various nervous systems—including the center, autonomic, and somatic nervous systems—is explored and presented, highlighting the potential for these devices to facilitate neurological treatments. By summarizing TENGs' operational details and the potential for clinical translation, this review also identifies challenges associated with the implantation and integration of neural electrodes and presents recent advances in solutions, aiming to reshape electric treatments for neurological diseases. [ABSTRACT FROM AUTHOR]

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Self-powered solar-blind detectors have important potential applications in military and civil fields, but their low responsivity and slow response speed limit their practical applications. Regulating the internal barrier height by doping is an effective means of optimizing the performance of self-powered detectors. In this work, a self-powered solar-blind detector with a Cu2O QDs/Sn:α-Ga2O3 nanorod array with an average diameter of 200–500 nm was prepared by a hydrothermal process and simple spin coating. In the absence of electrical power, the responsivity of the device reached 6.574 mA/W at a 254 nm light stimulation, which increased by 11.27 times that of the undoped photodetector. At the same time, the device also has a short optical response time of 0.2s/0.3s. These results can be attributed to the following reasons. (1) Sn doping increases the carrier concentration, thereby increasing the conductivity of α-Ga2O3. (2) In the interfacial depletion region of Cu2O QDs/Sn:α-Ga2O3, increasing the height of the built-in barrier can effectively separate the photogenerated electron–hole pairs. This work provides a simple and effective way to construct a high-performance self-powered solar-blind photodetector. [ABSTRACT FROM AUTHOR]

A new galvanic cell design of a self‐powered and 3D‐printable soft sensor showing health monitoring, object recognition, and contactless hand gesture recognition, is reported. The soft sensor consists of a 3D‐printed poly(acrylic acid) (PAA) hydrogel electrolyte layer, a soft anode layer, and a soft cathode layer. The anode layer is a 3D‐printed and Cu2+ cross‐linked poly(N,N‐dimethylacrylamide‐co‐3‐alanine‐2‐hydroxypropylmethacrylate) (PDA) hydrogel dispersed with Cu metal particles (PDA/Cu2+/Cu hydrogel), while the cathode layer is a bottom thin layer of the PAA hydrogel containing MnO2 (PAA/MnO2). Using graphite films as the soft electrodes, the soft sensor is finally assembled. The soft sensor has high force and temperature sensitivities. It gives different electric current responses under stretching, bending, pressing, and impact loading. The soft sensor is demonstrated to be useful in detecting human motion and physiological activities, e.g., breath. Based on the force and contactless temperature sensitivities, the soft sensor is used to recognize human hand gestures and plastic balls with different diameters. This 3D printable soft sensor with self‐powering, contactless motion capturing, and multi‐pimulus sensing capabilities illustrates a new pathway to make soft sensory devices for healthcare and human‐machine interaction applications. [ABSTRACT FROM AUTHOR]

2D materials with unique layer‐dependent electronic structure can bring precise control to their photocarrier dynamics for optimizing and expanding optoelectronic applications, while the challenge of controlling layer stacking makes the layer dependency law still underexplored in emerging 2D ternary metal chalcogenides. Herein, 2D rhombohedral‐phase ZnIn2S4 (R‐ZIS) with controllable layer thickness is achieved by confined‐growth strategy in high yield, exhibiting continuously tunable direct bandgap (2.39–2.77 eV) with evident upshift of conduction band minimum (CBM) and Fermi level (EF), demonstrated arising from the synergistic effect of reduced interlayer interaction with inevitably increasing Zn defects. Remarkably, the carrier dynamics of R‐ZIS in photoelectrochemical (PEC) device is successfully regulated by adjusted CBM and EF, resulting in continuously tunable optical absorption band, photocarrier separation efficiency, self‐powered capability, and dark current noise. Beneficial from tailored band structure and carrier dynamics, self‐powered PEC‐type photodetector with broadband photoresponse (254–765 nm), is achieved fast response speed (12.3/5.3 ms) and high responsivity (90.29 mA W−1) in multilayer R‐ZIS, while deep‐UV photodetector with ultra‐high specific detectivity (1.62 × 1012 Jones) at 254 nm in monolayer R‐ZIS, exhibiting the record performance in both fields. This work motivates the development of tailored band structure for 2D‐materials‐based optoelectronic devices in strategy and mechanism. [ABSTRACT FROM AUTHOR]

Ammonia, recognized as a perilous compound for both environmental and human health, necessitates detection of its varied concentrations in the air for environmental conservation and safety. This study introduces a novel self-powered ammonia gas sensor, operating at room temperature using a chitosan and tin dioxide (SnO₂) composite film. Designed based on the galvanic cell principle, the sensor eliminates the need for external power sources, making it ideal for various environmental and industrial applications. Advanced morphological and compositional analyses were conducted through field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDAX), confirming the effective integration of SnO₂ into the chitosan matrix, enhancing surface oxygen content and porosity. Fourier transform infrared (FTIR) spectroscopy revealed NH₂ groups in chitosan that interact with ammonia gas. The sensor demonstrated exceptional sensitivity and selectivity towards ammonia, with peak sensitivity reaching 26.13% at 50 ppm, significantly higher than pure chitosan's 17.14%. The sensor showed a substantial increase in electrical voltage in response to ammonia, effectively distinguishing it from gases such as acetone, ethanol, and toluene. This superior performance is attributed to the interaction between ammonia and NH₂ groups in chitosan, which promotes the release of trapped electrons. This research marks a significant advancement in gas detection technology, offering an eco-friendly, efficient, and reliable method for ammonia monitoring, essential for environmental protection and industrial safety. [ABSTRACT FROM AUTHOR]

The continuous worsening of the natural surroundings requires accelerating the exploration of green energy technology. Utilising ambient vibration to power electronic equipment constitutes an important measure to address the power crisis. Vibration power is widely dispersed in the surroundings, such as mechanical vibration, acoustic vibration, wind vibration, and water wave vibration. Collecting vibration energy is one of the research hotspots in the field of energy. Meanwhile, it is also an important way to solve the energy crisis. This paper illustrates the working principles and recent research progress of five known methods of vibrational energy harvesting, namely, electromagnetic, piezoelectric, friction electric, electrostatic, and magnetostrictive vibrational energy harvesters. The strengths and weaknesses of each method are summarised. At the end of the article, the future trends of micro-nano vibrational energy collectors are envisioned. [ABSTRACT FROM AUTHOR]

A self-powered in-nostril sensor based on the PVA thermoelectric hydrogel fiber was developed for long-term non-irritant anti-interference respiratory monitoring by discerning the temperature differences between the exhaled gas and skin in the nasal cavity. Owing to its slender structure and excellent pliability, the fiber sensor can be easily inserted into the nasal cavity without causing any discomfort. With the assistance of deep learning, the gel fiber-based respiratory monitoring strategy can actively identify seven respiratory patterns with an accuracy of 97.1%, providing a promising paradigm for early detection of respiratory diseases based on wearable bioelectronics. [Display omitted] Direct and consistent monitoring of respiratory patterns is crucial for disease prognostication. Although the wired clinical respiratory monitoring apparatus can operate accurately, the existing defects are evident, such as the indispensability of an external power supply, low mobility, poor comfort, and limited monitoring timeframes. Here, we present a self-powered in-nostril hydrogel sensor for long-term non-irritant anti-interference respiratory monitoring, which is developed from a dual-network binary-solvent thermogalvanic polyvinyl alcohol hydrogel fiber (d = 500 μm, L=30 mm) with Fe2+/Fe3+ ions serving as a redox couple, which can generate a thermoelectrical signal in the nasal cavity based on the temperature difference between the exhaled gas and skin as well as avoid interference from the external environment. Due to strong hydrogen bonding between solvent molecules, the sensor retains over 90 % of its moisture after 14 days, exhibiting great potential in wearable respiratory surveillance. With the assistance of deep learning, the hydrogel fiber-based respiration monitoring strategy can actively recognize seven typical breathing patterns with an accuracy of 97.1 % by extracting the time sequence and dynamic parameters of the thermoelectric signals generated by respiration, providing an alert for high-risk respiratory symptoms. This work demonstrates the significant potential of thermogalvanic gels for next-generation wearable bioelectronics for early screening of respiratory diseases. [ABSTRACT FROM AUTHOR]

Highlights The flexible single-walled carbon nanotube/titanium carbide composite films exhibit excellent thermoelectric (TE), high-temperature stable and flame-retardant properties. The assembled TE device achieves an ultrafast fire warning response time of ~ 0.1 s with a threshold voltage of 1 mV. The fire warning device demonstrates exceptional repeatability and long-term stability. The designed intelligent system is promising for next-generation self-powered remote IoT fire warning applications.

An efficient room-temperature self-powered, broadband (300 ​nm–1100 nm) photodetector based on a CuO–TiO2/TiO2/p-Si(100) heterostructure is demonstrated. The CuO–TiO2 nanocomposites were grown in a two-zone horizontal tube furnace on a 40 ​nm TiO2 thin film deposited on a p-type Si(100) substrate. The CuO–TiO2/TiO2/p-Si(100) devices exhibited excellent rectification characteristics under dark and individual photo-illumination conditions. The devices showed remarkable photo-response under broadband (300–1100 ​nm) light illumination at zero bias voltage, indicating the achievement of highly sensitive self-powered photodetectors at visible and near-infrared light illuminations. The maximum response of the devices is observed at 300 ​nm for an illumination power of 10 ​W. The response and recovery times were calculated as 86 ​ms and 78 ​ms, respectively. Moreover, under a small bias, the devices showed a prompt binary response by altering the current from positive to negative under illumination conditions. The main reason behind this binary response is the low turn-on voltage and photovoltaic characteristics of the devices. Under illumination conditions, the generation of photocurrent is due to the separation of photogenerated electron-hole pairs within the built-in electric field at the CuO–TiO2/TiO2 interface. These characteristics make the CuO–TiO2/TiO2 broadband photodetectors suitable for applications that require high response speeds and self-sufficient functionality.

Heterojunctions combining 2D and 3D perovskites have caused a surge in the research on X‐ray detectors. The enhanced charge transport facilitated by the built‐in electric field further amplifies the potential of this material system, paving the way for highly sensitive and efficient X‐ray detectors. In this study, PA2PbBr4 single‐crystal film with a thickness of 10 µm is successfully grown on the surface of MAPbBr3 substrate via liquid phase epitaxial method, forming a 2D/3D heterojunction. This innovative detector exhibits a dramatically enhanced sensitivity of 3.81 × 104 µC Gy−1 cm−2 at an X‐ray tube voltage of 70 keV and a bias of 50 V mm−1, along with an ultra‐low detection limit of 11.84 nGy s−1, surpassing the performance of the conventional MAPbBr3 X‐ray detectors by a factor of four and 2 × 103 times higher than that of commercialized α‐Se detectors. Furthermore, the 2D/3D heterojunction exhibits exceptional self‐powered X‐ray detection capabilities, achieving a remarkable sensitivity of 3562.26 µC Gy−1 cm−2 at 70 keV X‐ray tube voltage. This superior performance implies reduced energy consumption, high portability, decreased ion migration, and provides inspiration for the next generation of high‐performance X‐ray detectors. [ABSTRACT FROM AUTHOR]

Human–machine interactions (HMIs) have penetrated into various academic and industrial fields, such as robotics, virtual reality, and wearable electronics. However, the practical application of most human–machine interfaces faces notable obstacles due to their complex structure and materials, high power consumption, limited effective skin adhesion, and high cost. Herein, we report a self-powered, skin adhesive, and flexible human–machine interface based on a triboelectric nanogenerator (SSFHMI). Characterized by its simple structure and low cost, the SSFHMI can easily convert touch stimuli into a stable electrical signal at the trigger pressure from a finger touch, without requiring an external power supply. A skeleton spacer has been specially designed in order to increase the stability and homogeneity of the output signals of each TENG unit and prevent crosstalk between them. Moreover, we constructed a hydrogel adhesive interface with skin-adhesive properties to adapt to easy wear on complex human body surfaces. By integrating the SSFHMI with a microcontroller, a programmable touch operation platform has been constructed that is capable of multiple interactions. These include medical calling, music media playback, security unlocking, and electronic piano playing. This self-powered, cost-effective SSFHMI holds potential relevance for the next generation of highly integrated and sustainable portable smart electronic products and applications. [ABSTRACT FROM AUTHOR]

High‐energy excitons in transition metal dichalcogenides (TMDs), resulting from intrinsic van Hove singularities in the density of states, demonstrate strong ultraviolet light absorption capacity and significant potential for the development of high‐performance ultraviolet photovoltaic devices. Nevertheless, only a limited fraction of carriers from high‐energy excitons can be effectively utilized due to unique parallel band structures and unfavorable recombination processes. To efficiently exploit the high‐energy excitons, a two‐terminal photodetector based on multilayer WSe2 with a unilateral Schottky junction is designed. Benefiting from the strong built‐in electric field, a superior responsivity of 286 mA W−1 and near‐unity external‐quantum‐efficiency (EQE) of 98% is achieved at 360 nm. Transient absorption spectroscopy demonstrates that the high EQE is attributed to the efficient separation and transfer of high‐energy excitons achieved by the strong built‐in electric field, thus circumventing unfavorable recombination processes and enabling highly efficient utilization of high‐energy excitons. This work provides an effective strategy for constructing high‐performance and low‐power consumption ultraviolet photodetectors. [ABSTRACT FROM AUTHOR]

2D materials have garnered significant research attention due to their unique electrical and optical properties. Various photodetectors (PDs) based on 2D materials have been demonstrated to possess a high photoresponse, achieve specific light detection, and construct flexible devices. Among these, photoelectrochemical‐type (PEC) PDs are attracting increasing attention due to their facile fabrication processes, self‐powered capability, and high sensitivity. Compared with transitional solid‐state PDs based on 2D materials, research on 2D material‐based PEC PDs is still in its initial stages but exhibits promising potential for various applications. This paper comprehensively reviews recent advancements in 2D material‐based PEC PDs. The 2D materials for PEC PDs are first classified, and then the synthesis methods employed for their fabrication are briefly summarized. Later, the performance and performance optimization strategies of various 2D material‐based PEC PDs are discussed. Finally, the challenges and opportunities for developing high‐performance 2D material‐based PEC PDs are highlighted. [ABSTRACT FROM AUTHOR]

Vertical semiconductor van der Waals heterojunctions are essential for fabricating high-performance photodetectors. However, the range of the spectral response and defect states of semiconductor materials are two critical factors affecting the performance of photodetectors. In this work, the spectral response range of WS2 was changed through WS2 band gap regulation, and a self-powered vertical WS1.08Se0.92/Si heterojunction photodetector with MXene electrode was prepared by synthesizing WS1.08Se0.92 film on Si substrate and vertically stacking Ti3C2T x MXene on the film. Due to the electron collection of MXene and the wonderful junction quality of WS1.08Se0.92/Si, the photodetector can detect near-infrared light in the range of 980–1310 nm, which exceed the detection limit of WS1.08Se0.92. And the device had high sensitivity in the broadband. The responsivity was 4.58 A W−1, the specific detectivity was 4.58 × 1011 Jones, the on/off ratio was 4.95 × 103, and the fast response time was 9.81/9.03 μ s. These properties are superior to previously reported WS2-based photodetectors. Vertical structure, Energy band tuning, and MXene electrode provide a new idea for preparing broadband high-performance and self-powered photodetector. [ABSTRACT FROM AUTHOR]

The combination of the antisolvent method and additive passivation is an effective strategy to control the defects of organic-inorganic halide perovskite films. In this paper, CsSn0.2Pb0.8I3 QDs prepared by the mixed heating method were mixed with toluene solution to form an anti-solvent of different concentrations, and defect passivation and modification of self-supplied carbon-based MAPbI3 perovskite films were carried out. The results show that when the optimal additive concentration of 10 mg/mL CsSn0.2Pb0.8I3 QDs optimized perovskite active layer is applied to the self-powered perovskite photodetector, the original dark current of the device is reduced from 1.09 × 10− 9 A to 5.03 × 10− 11 A, which is about 95%. Responsiveness reaches a maximum of 0.45 A/W, which is 28% higher than 0.35 A/W before optimization. Compared with the detection rate increased from 2.72 × 1012 Jones to 2.53 × 1013 Jones (1 Jones = 1 cm∙Hz1/2∙W− 1), the detection capability of self-powered perovskite photodetector has been improved by nearly one order of magnitude. [ABSTRACT FROM AUTHOR]

Sn and S are environmentally friendly elements that are abundant in nature. The SnS 2 compound formed with these elements has intrinsic n-type electrical conductivity and a direct forbidden band gap of ∼2.2 eV. Therefore, it is a very promising compound for visible light optoelectronic applications. In this study, SnS 2 thin films were coated on p-Si substrates and pn heterojunction structures were obtained. By adding certain amounts of Na element to SnS 2 , the photosensitivity of the heterojunction devices increased tremendously and reached a high value of 3.2 × 104 under zero bias condition. It was observed that the prepared devices had excellent speeds and stability with rise and decay times of as low as 28 m s and 23 m s. Moreover, the devices were found to be sensitive to visible light even at ultra-low light intensity of ∼0.3 μW/cm2. Furthermore, the responsivity and specific detectivity values of the prepared photodetectors reach very high values of 11 A/W and 8.4 × 1013 Jones at this low light intensity. The NEP value drops to a low level of 2.7 × 10−15 WHz −1/2. In addition, the photocatalytic properties of Na-doped and undoped SnS 2 compound were also examined under visible LED light. Compared to undoped samples, photocatalytic efficiency increased by ∼42 % in Na-doped SnS 2 thin films. The findings clearly reveal that Na improves both photodetector device performance and the photocatalytic effect of the SnS 2 semiconductor. [ABSTRACT FROM AUTHOR]

Harvesting energy through light radiation is an attractive solution for powering wireless devices in the future. In particular, self-driven optoelectronic devices are especially attractive for low-energy devices on the Internet of Things. Two-dimensional (2D) materials at atomic scale thicknesses are very attractive for future self-powered optoelectronic devices due to not only their unique electronic and optical properties, but also the feasibility to fabricate desirable heterostructures, which differ from their bulk counterparts and conventional optoelectronic materials. In this review, we mainly summarized the mechanism and performance of self-powered optoelectronic devices based on 2D materials. The figure of merit and mechanism of self-driving optoelectronic devices including the interface-junction effect, bulk photovoltaic effect, and photothermoelectric effect are discussed in detail. In addition, the recent progress on the performance of self-powered optoelectronic devices based on 2D materials is compared, followed by the perspective of this field. This review is aimed to give a generalized knowledge of 2D self-powered optoelectronic devices, and thus prompt the exploration and development of novel functional devices based on 2D materials. [ABSTRACT FROM AUTHOR]

Wearable sensors are important components, converting mechanical vibration energy into electrical signals or other forms of output, which are widely used in healthcare, disaster warning, and transportation. However, the reliance on batteries limits the portability of wearable sensors and hinders their application in the field of Internet of Things. To solve this problem, we designed a miniaturized high-performance hybrid nanogenerator (MHP-HNG), which combined the functions of triboelectric sensing and electromagnetic power generation as well as the advantages of miniaturization. By optimizing the design of TENG and EMG, the wearable sensor achieved a voltage output of 14.14 V and a power output of 49 mW. Based on the wireless optical communication and wireless communication technologies, the wearable sensor achieved the integration of sensing, communication, and self-powered function, which is expected to realize health monitoring, emergency warning, and rehabilitation assistance, and further extend the potential application value in the medical field. [ABSTRACT FROM AUTHOR]

[Display omitted] Flexible self-powered bioelectronics (FSPBs), incorporating flexible electronic features in biomedical applications, have revolutionized the human–machine interface since they hold the potential to offer natural and seamless human interactions while overcoming the limitations of battery-dependent power sources. Furthermore, as biosensors or actuators, FSPBs can dynamically monitor physiological signals to reveal real-time health abnormalities and provide timely and precise treatments. Therefore, FSPBs are increasingly shaping the landscape of health monitoring and disease treatment, weaving a sophisticated and personalized bond between humans and health management. Here, we examine the recent advanced progress of FSPBs in developing working mechanisms, design strategies, and structural configurations toward personalized health management, emphasizing its role in clinical medical scenarios from biophysical/biochemical sensors for sensing diagnosis to robust/biodegradable actuators for intervention therapy. Future perspectives on the challenges and opportunities in emerging multifunctional FSPBs for the next-generation health management systems are also forecasted. [ABSTRACT FROM AUTHOR]

The discovery of triboelectric nano-generators (TENGs) has resulted in the invention and development of self-powered electronics and devices. TENGs offer numerous benefits including their portability, affordability, and sustainable micro-scale energy harvesting in the realm of self-powered sensors and portable devices. TENGs have the capability to function as an autonomous power source. Integration of TENG with electrochemical processes can facilitate self-powered electrochemistry such as water splitting (or electrolysis) for H 2 production, thereby eliminating the requirement for an external power supply. This review primarily centers on the operation and the recent advancements of TENGs in self-powered water-splitting for clean and environment-friendly H 2 production utilizing renewable energy sources including wind, wave, and low-scale mechanical energy. The concept of conducting water-splitting without reliance on an external power source holds the potential for significant use in the field of clean and green H 2 production with cost advantages, sustainability, and other environmental benefits. [Display omitted] • Analysis of principle and working of triboelectric nano-generators (TENGs). • Utilization of TENGs in self-powered water splitting devices. • Review on the recent advances in conversion of wind, wave and low-scale mechanical energy by TENG to clean and green H 2 production. • Summarized benefits, challenges and perspective of TENG based self-powered electrolysis. [ABSTRACT FROM AUTHOR]

The integration of electrochromic devices and energy storage systems in wearable electronics is highly desirable yet challenging, because self‐powered electrochromic devices often require an open system design for continuous replenishment of the strong oxidants to enable the coloring/bleaching processes. A self‐powered electrochromic device has been developed with a close configuration by integrating a Zn/MnO2 ionic battery into the Prussian blue (PB)‐based electrochromic system. Zn and MnO2 electrodes, as dual shared electrodes, the former one can reduce the PB electrode to the Prussian white (PW) electrode and serves as the anode in the battery; the latter electrode can oxidize the PW electrode to its initial state and acts as the cathode in the battery. The bleaching/coloring processes are driven by the gradient potential between Zn/PB and PW/MnO2 electrodes. The as‐prepared Zn||PB||MnO2 system demonstrates superior electrochromic performance, including excellent optical contrast (80.6%), fast self‐bleaching/coloring speed (2.0/3.2 s for bleaching/coloring), and long‐term self‐powered electrochromic cycles. An air‐working Zn||PB||MnO2 device is also developed with a 70.3% optical contrast, fast switching speed (2.2/4.8 s for bleaching/coloring), and over 80 self‐bleaching/coloring cycles. Furthermore, the closed nature enables the fabrication of various flexible electrochromic devices, exhibiting great potentials for the next‐generation wearable electrochromic devices. [ABSTRACT FROM AUTHOR]

Recently, IoT-based sensor networks for monitoring environmental parameters have attracted research and development groups due to their numerous advantages. However, these battery-powered devices experience the difficulties of periodic recharge or replacement. Therefore, to provide a sustainable and continuous power supply, piezoelectric energy harvesters can be used where the wired power connection is not feasible due to inaccessible setup or hazardous environment. The efficiency of piezoelectric converters is determined by their geometrical configuration and the materials used. This paper addresses the analytical modeling of a unimorph piezoelectric harvester and the optimization of harvester geometry to improve the output power and resonance frequency. The harvester geometry is modeled using Finite Element Method (FEM), and the RADAR plot is used to optimize the harvester width for maximum output. The FEM-optimized model is experimentally tested with the help of a controlled vibratory system designed and developed for this purpose. The optimized model is a dumbbell-shaped harvester with 390% more open circuit output voltage and 9.6% reduced resonant frequency compared to a rectangular harvester. The maximum power of 59.9μW is harvested across 1MΩ load with a power density of 1mWcm-3 at 141Hz resonant frequency. [ABSTRACT FROM AUTHOR]