Tunable photochemical deposition of silver nanostructures on layered ferroelectric CuInP2S6

Abstract

Two-dimensional layered ferroelectric materials, such as CuInP2S6 (CIPS), are promising candidates for novel and high-performance photocatalysts, owing to their ultrathin layer thickness, strong interlayer coupling, and intrinsic spontaneous polarization, while how to control the photocatalytic activity in layered CIPS remains unexplored. In this work, we report for the first time, the photocatalytic activity of ferroelectric CIPS for the chemical deposition of silver nanostructures (AgNSs). The results show that the shape and spatial distribution of AgNSs on CIPS are tunable by controlling layer thickness, environmental temperature, and light wavelength. The ferroelectric polarization in CIPS plays a critical role in tunable AgNS photodeposition, as evidenced by layer thickness and temperature dependence experiments. We further reveal that AgNS photodeposition process starts from active site creation, selective nanoparticle nucleation/aggregation, to continuous film formation. Moreover, AgNS/CIPS heterostructures prepared by photodeposition exhibit excellent resistance switching behavior and good surface enhancement Raman Scattering activity. Our findings provide new insight into the photocatalytic activity of layered ferroelectrics and offer a new material platform for advanced functional device applications in smart memristors and enhanced chemical sensors.

Selective Surface Modification and Layer Thinning of MoS2 via Ultraviolet-Light Irradiation in an Ionic Solution: Implications for Multifunctional Nanoelectronic Devices

“…We also have calculated the coverage of Ag nanostructures on the surface of MoS 2 using the equation S Ag / S MoS 2 × 100%, where S Ag and S MoS 2 are the total areas of Ag nanostructures and pristine MoS 2 , respectively. The fitting curve in Figure a demonstrates a typical parabola relationship between S Ag / S MoS 2 and UV-irradiation time, similar to the photocatalytic behavior of Ag nanostructure deposition on other 2D materials …”

“…The fitting curve in Figure 2a demonstrates a typical parabola relationship between S Ag /S MoSd 2 and UV-irradiation time, similar to the photocatalytic behavior of Ag nanostructure deposition on other 2D materials. 37 To gain a better understanding of the surface modification process and its effect on the electrical properties of MoS 2 , we design a FET device in a two-terminal configuration (Figure 2b) and perform in situ electrical measurement. Figure 2c shows the optical image of a 1L MoS 2 device on a SiO 2 /Si To confirm the doping effect, we perform in situ electrical transport measurement (Figure 2f).…”

Interface-Tuning of Ferroelectricity and Quadruple-Well State in CuInP2S6via Ferroelectric Oxide

“…Layered van der Waals (vdW) ferroelectric CuInP 2 S 6 (CIPS) hosts unconventional quadruple-well energy and high ionic conductivity, , which lead to various exotic phenomena, including negative piezoelectricity, thickness-dependent in-plane polarization, giant electrostriction enabled strain tunability, strong coupling of ferroelectric polarization with ionic migration and topography variation, − and the self-rectifying memristor effect . Compared with other vdW ferroelectric semiconductors, the above room temperature Curie temperature (bulk T C ∼ 42 °C), large band gap ( E g ∼ 2.9 eV), and large out-of-plane polarization ( P ∼ 4 μC/cm 2 ) make CIPS the most promising candidate for developing flexible and transparent nanoelectronic and optoelectronic devices, such as nonvolatile memory, − negative capacitance transistors, , memristors, , rectifiers, , photocatalysis, and photovoltaics …”