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Liquid metal (LM) nanodroplets possess intriguing surface properties, thus offering promising potential in chemical synthesis, catalysis, and biomedicine. However, the reaction kinetics and product growth at the surface of LM nanodroplets are significantly influenced by the interface involved, which has not been thoroughly explored and understood. Here, we propose an interface engineering strategy, taking a spontaneous galvanic reaction between Ga0 and AuCl4- ions as a representative example, to successfully modulate the growth of heterostructures on the surface of Ga-based LM nanodroplets by establishing a dielectric interface with a controllable thickness between LM and reactive surroundings. Combining high-resolution electron energy-loss spectroscopy (EELS) analysis and theoretical simulation, it was found that the induced charge distribution at the interface dominates the spatiotemporal distribution of the reaction sites. Employing tungsten oxide (WOx) with varying thicknesses as the demonstrated dielectric interface of LM, Ga@WOx@Au with distinct core-shell-satellite or dimer-like heterostructures has been achieved and exhibited different photoresponsive capabilities for photodetection. Understanding the kinetics of product growth and the regulatory strategy of the dielectric interface provides an experimental approach to controlling the structure and properties of products in LM nanodroplet-involved chemical processes.
RESUMO
With the continuous exploration of low-dimensional nanomaterials, two dimensional metal oxides (2DMOs) has been received great interest. However, their further development is limited by the high cost in the preparation process and the unstable states caused by the polarization of surface chemical bonds. Recently, obtaining mental oxides via liquid metals have been considered a surprising method for obtaining 2DMOs. Therefore, how to scientifically choose different preparation methods to obtain 2DMOs applying in different application scenarios is an ongoing process worth discussing. This review will provide some new opportunities for the rational design of 2DMOs based on liquid metals. Firstly, the surface oxidation process and in situ electrical replacement reaction process of liquid metals are introduced in detail, which provides theoretical basis for realizing functional 2DMOs. Secondly, by simple sticking method, gas injection method and ultrasonic method, 2DMOs can be obtained from liquid metal, the characteristics of each method are introduced in detail. Then, this review provides some prospective new ideas for 2DMOs in other energy-related applications such as photodegradation, CO2 reduction and battery applications. Finally, the present challenges and future development prospects of 2DMOs applied in liquid metals are presented.
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Herein, FePS3/reduced graphene oxide heterostructure has been prepared via a typical hydrothermal process, and flexible photodetectors based on hybrids have been subsequently fabricated. The photoresponse measurement results demonstrate that the photodetector exhibits obvious photoelectric conversion behavior without applied potential, indicating that the device possesses the capability to be self-powered. In addition, the photocurrent density of the as-fabricated photodetectors reaches up to 125 nA cm-2under 90 mW cm-2illumination intensity without an external power source, which is 5.86 times higher than single FePS3-based devices. Furthermore, the maximum attenuation in photocurrent density of the as-fabricated flexible photodetectors measured at -0.3 V after different bending cycles and bending angles is 29.8% and 17.7%, respectively. These results demonstrate that the as-fabricated photodetectors have excellent flexibility and provide a simple and effective strategy for the construction of flexible photodetectors.
RESUMO
Here, a photoelectrochemical (PEC) photodetector with good flexibility and high photoresponsivity was successfully fabricated in a vertical structure, where the MXene (Ti2CTx) nanosheet and carbon black electrode were separated by adenosine triphosphate/nicotinamide adenine dinucleotide phosphate (ATP/NADPH)-incorporated solid-state electrolyte. The photocurrent and photoresponsivity can reach 1.84 µA/cm2 and 8.89 µA/W, respectively, under a light intensity of 90 mW/cm2 at a bias potential of 0.6 V, which are approximately 2.3 times those of Ti2CTx nanosheets. The addition of ATP and NADPH to the electrolyte also leads to a large decrease of the rise time from 0.76 to 0.26 s. Furthermore, the photodetector can continue to function and maintain stability under 45° bending and after 500 cycles of bending, indicating a robust device structure and great flexibility. The performance enhancement of the PEC photodetector can be attributed to the synergistic effect of electrolyte additives on Ti2CTx nanosheets, where ATP and NADPH greatly enhance the circulation and utilization of photogenerated carriers. This work suggests that the incorporation of chloroplast-inspired carrier circulation with two-dimensional nanosheets could achieve efficient light-current conversion, providing a new strategy to improve the performance of PEC-type photodetectors.
RESUMO
As a sustainable environmental governance strategy and energy conversion method, photocatalysis has considered to have great potential in this field due to its excellent optical properties and has become one of the most attractive technologies today. Among 2D materials, the emerging two-dimensional (2D) monoelemental materials mainly distributed in the -IIIA, -IVA, -VA and -VIA groups and show excellent performance in solar energy conversion due to their graphene-like 2D atomic structure and unique properties, thereby drawing increasing attention. This review briefly summarizes the preparation processes and fundamental properties of 2D single-element nanomaterials, as well as various modification strategies and adjustment mechanisms to enhance their photocatalytic properties. In particular, this article comprehensively discusses the related practical applications of 2D single-element materials in the field of photocatalysis, including photocatalytic degradation for contaminants removal, photocatalytic pathogen inactivation, photocatalytic fouling control and photocatalytic energy conversion. This review will provide some new opportunities for the rational design of other excellent photocatalysts based on 2D monoelemental materials, as well as present tremendous novel ideas for 2D monoelemental materials in other environmental conservation and energy-related applications, such as supercapacitors, electrocatalysis, solar cells, and so on.
RESUMO
Photoelectric detectors based on binary transition metal chalcogenides have attracted widespread attention in recent years. However, due to the high-temperature synthesis of binary TMD, high-density deep-level defect states may be generated, leading to poor responsiveness or a long response time. Besides, the addition of an alloy will change the DLDSs from deep to shallow energy levels caused by S vacancies. In this paper, MoS2(1-x)Se2x nanostructures were synthesized by a hydrothermal method, and a novel type of photodetector was fabricated by using the synthesized material as a light sensitive material. The MoSSe-based photodetector not only has a high photocurrent, but also exhibits a wide spectral response in the range of 405 nm to 808 nm. At the same time, it can achieve a responsivity of 1.753 mA W-1 under 660 nm laser irradiation of 1.75 mW mm-2. Therefore, this work can be considered as a method of constructing a new type of photodetector with a simple process and low cost.