Plasmonic imaging of the layer-dependent electrocatalytic activity of two-dimensional catalysts

Abstract

Studying the localized electrocatalytic activity of heterogeneous electrocatalysts is crucial for understanding electrocatalytic reactions and further improving their performance. However, correlating the electrocatalytic activity with the microscopic structure of two-dimensional (2D) electrocatalysts remains a great challenge due to the lack of in situ imaging techniques and methods of tuning structures with atomic precision. Here, we present a general method of probing the layer-dependent electrocatalytic activity of 2D materials in situ using a plasmonic imaging technique. Unlike the existing methods, this approach was used to visualize the surface charge density and electrocatalytic activity of single 2D MoS2 nanosheets, enabling the correlation of layer-dependent electrocatalytic activity with the surface charge density of single MoS2 nanosheets. This work provides insights into the electrocatalytic mechanisms of 2D transition metal dichalcogenides, and our approach can serve as a promising platform for investigating electrocatalytic reactions at the heterogeneous interface, thus guiding the rational design of high-performance electrocatalysts.

Molybdenum Disulfide Flakes as Platforms for the Photoconversion of 4-Nitrothiophenol

“…In the case of the monolayer, the PICT of electrons is more efficient, which is clearly evidenced by the PL spectra, as shown in Figure c,d, with a decrease in PL intensity as compared to the bilayer case. This result is coherent with a higher mobility and higher surface charge density over MoS 2 monolayers. , In the case of a bilayer, an energy barrier impedes the charge mobility between MoS 2 layers, thus decreasing the efficiency of the charge transfer.…”

“…This result is coherent with a higher mobility and higher surface charge density over MoS 2 monolayers. 51,52 In the case of a bilayer, an energy barrier impedes the charge mobility between MoS 2 layers, thus decreasing the efficiency of the charge transfer.…”

Deep-Learning Driven, High-Precision Plasmonic Scattering Interferometry for Single-Particle Identification

“…Usually, surface plasmon resonance is highly sensitive to the surface charge density, , which can induce an image background oscillation corresponding to the external electrical potential, ,, reducing the precision of single nanoparticle characterization. Surprisingly, our method successfully classified nanoparticles without being influenced by such variations.…”

“…Unlike the previous approaches using manual analysis frame-by-frame, 20,22 our method enabled direct and automatic imaging of nanoparticle composition variations, avoiding post data processing, which significantly improved the analysis throughput. Usually, surface plasmon resonance is highly sensitive to the surface charge density, 31,32 which can induce an image background oscillation corresponding to the external electrical potential, 17,33,34 reducing the precision of single nanoparticle characterization. Surprisingly, our method successfully classified nanoparticles without being influenced by such variations.…”

In Operando Study of Charge Modulation in MoS2 Transistors by Excitonic Reflection Microscopy

“…Such biosensing capability was further confirmed in a different article by Zhu et al, using a total internal reflectance configuration where the binding kinetics of protein molecules on MoS 2 were measured. Zhao et al also imaged charge in MoS 2 using surface plasmon resonance imaging …”