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Different types of devices with modulable resistance are attractive for the significant potential applications such as sensors, information storage, computation, etc. Although extensive research has been reported on resistance effects, there is still a need for exploring new mechanisms that offer advantages of low power consumption, high sensitivity, and long-term stability. Here, we report a graphene–Si based spatial-dependence photo-rheostat (SDPR), which enables bipolar resistance modulation in the range of 5 mm with a resistance sensitivity exceeding 1,000 Ω/mm at operating wavelengths from visible to near infrared band (1,550 nm). Especially, at ultra-low energy consumption, the device can achieve modulation of even 5 orders of magnitude of resistance and response speed up to 10 kHz. A theoretical model based on carrier dynamics is established to reveal the diffusion and drift of carriers as a mechanism explaining such experimental phenomenon. This work provides a new avenue to modulate resistance at low power consumption as novel opto-potentiometers in various photoelectric applications.

The topological insulator 2D Bi2Se3 is promising for electronic devices due to its unique electronic properties; however, it is challenging to prepare antioxidative nanosheets since Bi2Se3 is prone to oxidation. Surface passivation using ligand agents after Bi2Se3 exfoliation works well to protect the surface, but the process is time-consuming and technically challenging; a passivation agent that is stable under a highly biased potential is significant for in situ passivation of the Bi2Se3 surface. In this work, the roles of halide anions (Cl−, Br−, and I−) in respect of the chemical properties of synthetic Bi2Se3 nanosheets during electrochemical intercalated exfoliation were investigated to determine the antioxidation capacity. It was found that Bi2Se3 nanosheets prepared in a solution of tetrabutylammonium chloride (TBA+ and Cl−) have the best oxidation resistance via the surface bonding of Bi with Cl, which promotes obtaining better device stability. This work paves an avenue for adjusting the components of the electrolyte to further promote the stability of 2D Bi2Se3-nanosheet-based electronic devices. [ABSTRACT FROM AUTHOR]

Photoreduction of CO2 provides an appealing way to alleviate the energy crisis and manage the global carbon balance but is limited by the high activation energy and the rate‐limiting proton transfer. We now develop a dual‐site strategy for high‐efficiency CO2 conversion through polarizing CO2 molecules at pyridine N vacancies and accelerating the intermediate protonation by protonated pyridine N adjacent to nitrogen vacancies on polymeric carbon nitride. Our photocatalysts with atomic‐level engineered active sites manifest a high CO production rate of 1835 μmol g−1 h−1, 183 times higher than the pristine bulk carbon nitride. Theoretical prediction and experimental studies confirm that such excellent performance is attributed to the synergistic effect between vacant and protonated pyridine N in decreasing the formation energy of the key *COOH intermediates and the efficient electron transfer relay facilitated by the defect‐induced shallow trap state and homogeneous charge mediators. [ABSTRACT FROM AUTHOR]

An efficient water oxidation photocatalyst is imperative for the realization of artificial photosynthesis. Herein, a cooperative strategy is represented that enables 2D structure tailoring and lattice distortion engineering simultaneously over a BiVO4 photocatalyst for efficient visible‐light‐driven oxygen evolution reaction (OER). Specifically, the lattice distortion engineering is achieved through the introduction of a sodium (Na+) additive during the ion exchange process. Structural characterizations suggest the formation of ultrathin 2D monoclinic BiVO4 nanoflakes with shrank VO and elongated BiO bonds. Mechanistic investigations reveal the advantages of ultrathin 2D features for exposing more (010) active facets and shortening the required migration distance for charge carriers to reach the catalytic surface. More importantly, the lattice distortion effect is found to crucially govern the charge carrier dynamics and catalytic surface behavior of BiVO4 photocatalyst, endowing the optimized sample with an outstanding photocatalytic OER performance triggering up to 69.4% apparent quantum efficiency over Fe3+ sacrificial solution. These findings highlight the functional application of morphology and dimensional modification, as well as lattice distortion engineering in synthesizing superior monoclinic BiVO4 photocatalyst for efficient visible‐light‐driven water oxidation. [ABSTRACT FROM AUTHOR]

Broadband photodetectors have attracted much attention due to their multispectral response properties and show great potential in the fields of optical sensing, multispectral imaging, and optical communications. Palladium telluride (PdTe 2 ) is highly competitive in broadband detection due to its tunable bandgap and nonlinear optical properties. However, the low response speed hinders further improvement in the performance of PdTe 2 -based broadband photodetectors. In this work, we present island-type ZnO@PdTe 2 composites on Si as a heterojunction photodetector exhibiting highly sensitive photodetection capabilities in a wide band from the solar-blind region (254 nm) to the short-infrared (1.55 μm). Due to the island-type morphology of the ZnO@PdTe 2 composites effectively enhancing light absorption and the ZnO@PdTe 2 /Si stacks forming a type-II heterojunction accelerating carrier separation, the devices have an ultrafast response (1.58/1.34 μs), a detectivity of up to 1.56 × 10 13 Jones, and a sensitivity of up to 10 7 cm 2 /W. A triple-channel color imaging system and a dual-channel data transmission system were developed based on the excellent and stable performance of the device. This study demonstrates the great potential of ZnO@PdTe 2 /Si vertical heterojunction photodetectors for high-speed, wide-band, multiscenario optical communication.

Photo-assisted ion batteries utilize light to boost capacity but face cycling instability due to complex charge/ion transfer under illumination. This study identified photo-induced proton transfer (photo-induced PT) as a significant process in photo-(dis)charging of widely-used V 2 O 5 -based zinc-ion batteries, contributing to enhanced capacity under illumination but jeopardizing photo-stability. Photo-induced PT occurs at 100 ps after photo-excitation, inducing rapid proton extraction into V 2 O 5 photoelectrode. This process creates a proton-deficient microenvironment on surface, leading to repetitive cathode dissolution and anode corrosion in each cycle. Enabling the intercalated protons from photo-induced PT to be reversibly employed in charge-discharge processes via the anode-alloying strategy achieves high photo-stability for the battery. Consequently, a ~54 % capacity enhancement was achieved in a V 2 O 5 -based zinc-ion battery under illumination, with ~90 % capacity retention after 4000 cycles. This extends the photo-stability record by 10 times. This study offers promising advancements in energy storage by addressing instability issues in photo-assisted ion batteries., (© 2024 Wiley‐VCH GmbH.)

The structure and configuration of reaction centers, which dominantly govern the catalytic behaviors, often undergo dynamic transformations under reaction conditions, yet little is known about how to exploit these features to favor the catalytic functions. Here, we demonstrate a facile light activation strategy over a TiO 2 -supported Cu catalyst to regulate the dynamic restructuring of Cu active sites during low-temperature methanol steam reforming. Under illumination, the thermally deactivated Cu/TiO 2 undergoes structural restoration from inoperative Cu 2 O to the originally active metallic Cu caused by photoexcited charge carriers from TiO 2 , thereby leading to substantially enhanced activity and stability. Given the low-intensity solar irradiation, the optimized Cu/TiO 2 displays a H 2 production rate of 1724.1 μmol g -1 min -1 , outperforming most of the conventional photocatalytic and thermocatalytic processes. Taking advantages of the strong light-matter-reactant interaction, we achieve in situ manipulation of the Cu active sites, suggesting the feasibility for real-time functionalization of catalysts.

The application of 2D materials-based flexible electronics in wearable scenarios is limited due to performance degradation under strain fields. In contrast to its negative role in existing transistors or sensors, herein, we discover a positive effect of strain to the ammonia detection in 2D PtSe 2 . Linear modulation of sensitivity is achieved in flexible 2D PtSe 2 sensors via a customized probe station with an in situ strain loading apparatus. For trace ammonia absorption, a 300% enhancement in room-temperature sensitivity (31.67% ppm -1 ) and an ultralow limit of detection (50 ppb) are observed under 1/4 mm -1 curvature strain. We identify three types of strain-sensitive adsorption sites in layered PtSe 2 and pinpoint that basal-plane lattice distortion contributes to better sensing performance resulting from reduced absorption energy and larger charge transfer density. Furthermore, we demonstrate state-of-the-art 2D PtSe 2 -based wireless wearable integrated circuits, which allow real-time gas sensing data acquisition, processing, and transmission through a Bluetooth module to user terminals. The circuits exhibit a wide detection range with a maximum sensitivity value of 0.026 V·ppm -1 and a low energy consumption below 2 mW.

Photoreduction of CO 2 provides an appealing way to alleviate the energy crisis and manage the global carbon balance but is limited by the high activation energy and the rate-limiting proton transfer. We now develop a dual-site strategy for high-efficiency CO 2 conversion through polarizing CO 2 molecules at pyridine N vacancies and accelerating the intermediate protonation by protonated pyridine N adjacent to nitrogen vacancies on polymeric carbon nitride. Our photocatalysts with atomic-level engineered active sites manifest a high CO production rate of 1835 μmol g -1  h -1 , 183 times higher than the pristine bulk carbon nitride. Theoretical prediction and experimental studies confirm that such excellent performance is attributed to the synergistic effect between vacant and protonated pyridine N in decreasing the formation energy of the key *COOH intermediates and the efficient electron transfer relay facilitated by the defect-induced shallow trap state and homogeneous charge mediators., (© 2022 Wiley-VCH GmbH.)