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Flexible optoelectronics is a rapidly growing field, with a wide range of potential applications. From wearable sensors to bendable solar cells, curved displays, and curved focal plane arrays, the possibilities are endless. The criticality of flexible photodetectors for many of these applications is acknowledged, however, devices that are demonstrated thus far are limited in their spectral range. In this study, flexible photodetectors are demonstrated using a VOx nanoparticle ink, with an extremely broad operating wavelength range of 0.4 to 20 µm. This ink is synthesized using a simple and scalable wet-chemical process. These photodetectors operate at room temperature and exhibit minimal variance in performance even when bent at angles of up to 100 ° at a bend radius of 6.4 mm. In addition, rigorous strain testing of 100 bend and release cycles revealed a photoresponse with a standard deviation of only 0.55%. This combination of mechanical flexibility, wide spectral response, and ease of fabrication makes these devices highly desirable for a wide range of applications, including low-cost wearable sensors and hyperspectral imaging systems.

Bulk black phosphorous (bP) exhibits excellent infrared (IR) optoelectronic properties, but most reported bP IR photodetectors are fabricated from single exfoliated flakes with lateral sizes of < 100 µm. Here, scalable thin films of bP suitable for IR photodetector arrays are realized through a tailored solution‐deposition method. The properties of the bP film and their protective capping layers are optimized to fabricate bP IR photoconductors exhibiting specific detectivities up to 4.0 × 108 cm Hz1/2 W−1 with fast 30/60 µs rise/fall times under λ = 2.2 µm illumination. The scalability of the bP thin film fabrication is demonstrated by fabricating a linear array of 25 bP photodetectors and obtaining 25 × 25 pixel IR images at ≈203 ppi with good spatial fidelity. This research demonstrates a commercially viable method of fabricating scalable bP thin films for optoelectronic devices including room temperature‐operable IR photodetector arrays. [ABSTRACT FROM AUTHOR]

Ultrathin transparent semiconducting oxides have attracted considerable attention in multifunctional electronic and optoelectronic devices, owing to their exciting physical properties and excellent stability. However, due to their wide bandgap, absorption in the visible region is very limited. Here, we show enhanced light–matter interactions by integrating plasmonic gold nanoparticles onto ultrathin SnO2 nanosheets, leading to higher optical absorption in the visible spectra. In this work, a vacuum-free liquid metal printing technique is used to deposit large-area ∼1.9 nm thick SnO2 nanosheets, which were then decorated with gold nanoparticles by utilizing an electrostatic self-assembly technique. The enhancement of the electric field due to localized surface plasmon resonance and plasmon-induced hot electron generation at the Au–SnO2 interface is verified utilizing COMSOL simulations. Moreover, experimental observations of fabricated photodetectors based on the Au–SnO2 hybrid structure demonstrate a broadband spectral response ranging from ultraviolet to visible wavelengths. In particular, we observe an improved room temperature photoresponsivity of ∼950 mA W–1 and a 17-fold enhancement in photocurrent at a 400 nm wavelength as compared to bare SnO2. This work provides a viable route to tune the optical properties of wide bandgap 2D functional oxides, making them attractive for large-area nanoscale broadband photodetectors and optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of a magnetic sodium alginate hydrogel for efficient adsorption of heavy metal ions. The hydrogel, composed of sodium alginate, demonstrates a network structure that facilitates effective metal ion adsorption. Utilizing magnetic forces, the hydrogel can be easily separated and regenerated, exhibiting excellent recyclability. Compared to traditional adsorbents, the magnetic sodium alginate hydrogel shows significantly improved adsorption capacity, particularly for Pb2+ ions. At pH ca. 4 and an adsorption time of 120 min, the hydrogel achieves a maximum adsorption capacity of 137 mg/g for Pb2+, with an adsorption rate of 83 %. The adsorption kinetics follow a pseudo-second-order equation, while thermodynamically, the process adheres to the Freundlich adsorption model, with capacity positively correlated with temperature and concentration. The negative ΔH value indicates an exothermic and spontaneous adsorption process. In competitive adsorption experiments, the hydrogel demonstrates strong selective adsorption towards Pb2+. It also exhibits excellent reusability, maintaining 80 % adsorption capacity after 10 cycles. The magnetic sodium alginate composite material possesses favorable recyclability and convenient magnetic separation properties, offering significant potential in various applications. [ABSTRACT FROM AUTHOR]

Miniaturization and energy consumption by computational systems remain major challenges to address. Optoelectronics based synaptic and light sensing provide an exciting platform for neuromorphic processing and vision applications offering several advantages. It is highly desirable to achieve single‐element image sensors that allow reception of information and execution of in‐memory computing processes while maintaining memory for much longer durations without the need for frequent electrical or optical rehearsals. In this work, ultra‐thin (<3 nm) doped indium oxide (In2O3) layers are engineered to demonstrate a monolithic two‐terminal ultraviolet (UV) sensing and processing system with long optical state retention operating at 50 mV. This endows features of several conductance states within the persistent photocurrent window that are harnessed to show learning capabilities and significantly reduce the number of rehearsals. The atomically thin sheets are implemented as a focal plane array (FPA) for UV spectrum based proof‐of‐concept vision system capable of pattern recognition and memorization required for imaging and detection applications. This integrated light sensing and memory system is deployed to illustrate capabilities for real‐time, in‐sensor memorization, and recognition tasks. This study provides an important template to engineer miniaturized and low operating voltage neuromorphic platforms across the light spectrum based on application demand. [ABSTRACT FROM AUTHOR]

In the process of development, new media presents a completely different development mode from traditional media, namely, platform development mode. Under the effect of network effect, the new media platform can quickly gather a large number of users, and integrate the resources of all the endpoints on the platform through the platform operation, so that the information production becomes efficient and the phenomenon of collaborative production appears. The value of media platform development is mainly reflected in the construction of its bilateral economic model, and the key to the construction of the bilateral model lies in the transformation from the scale economy of the demand side to the scope economy of the supply side. This paper explores a service-oriented new media operation platform under the bilateral market economy mode, to construct a price structure for bilateral users, from the perspective of free mechanism, attention economy and supply side economies of scope. This new media operation platform can break the barriers of single information flow, build unlimited value-added services, promote the integration of information flow, capital flow and logistics platform, and thus create a service-oriented new media platform.

Photodetectors formed with layered two‐dimensional (2D) materials have shown significant potential for integration with photonic circuits, offering fast, high responsivity and low noise detection over a broad range of optical wavelengths. However, only preliminary trials of this concept have been performed on emerging photonics platforms such as lithium niobate on insulator (LNOI). In this study, a novel architecture consisting of ≈15 nm thick layered black phosphorus (bP) photoconductors draped over LNOI waveguides is demonstrated. The performance of these detectors is studied across the telecom bands at room temperature, and a high extrinsic responsivity of 148 mA W−1 is measured at λ = 1550 nm under low bias conditions (VDS = 0.3 V). The spectral response of the detectors is broad allowing the response of other photonic components, such as fiber‐to‐chip grating couplers, to be characterized in situ, without need to out‐couple the light. Finally, the speed of the bP detectors is found to be beyond our instrumentation, setting 100 ns as an upper‐limit rise/fall time, with the actual speed of the bP detector likely to be much faster. [ABSTRACT FROM AUTHOR]