Nanoparticle formation under electron microscope.

Unlocking the Secrets of Nanomaterials: How Advanced Microscopy is Revolutionizing Material Science

Lena Kashyap in Tech & Innovation June 2025 • 4 min read.

"Explore how sub-sampling techniques in electron microscopy are enhancing our understanding of dynamic processes in liquids, paving the way for new material designs."

The synthesis of nanomaterials from solutions holds immense importance across various fields, including materials science, atmospheric studies, biological interactions, and energy storage. Observing the growth and behavior of these nanostructures in real-time is crucial, but traditional methods often fall short due to limitations in resolution and the disruptive effects of the observation techniques themselves.

Recent advancements in high-resolution scanning transmission electron microscopy (S/TEM) with in-situ liquid stages have opened new avenues for direct observation of nucleation and growth phenomena. These setups allow scientists to witness material transformations under different conditions, offering insights previously unattainable. However, the electron beam used for imaging can alter the local chemistry of the solution, leading to artifacts and hindering accurate analysis.

To bridge the gap between real-world conditions and TEM observations, researchers are focusing on minimizing electron dose and maximizing the information extracted per electron. This drive has led to the development of innovative techniques like sub-sampling and inpainting, which promise to revolutionize how we study dynamic processes in liquids.

Sub-Sampling and Inpainting: A Game-Changer in Electron Microscopy?

Nanoparticle formation under electron microscope.

Sub-sampling and inpainting techniques represent a significant leap forward in STEM imaging. Instead of capturing every pixel in an image, this approach acquires only a fraction of the data randomly. The missing information is then intelligently filled in using algorithms related to compressive sensing. This dramatically reduces the electron dose required, minimizing beam-induced alterations to the sample.

While still evolving, sub-sampled acquisitions have already demonstrated the potential to improve dose/resolution relationships in STEM images. By carefully controlling the electron beam, researchers can achieve high-quality imaging during in-situ liquid experiments, gaining unprecedented control over nucleation and growth kinetics.

Reduced Electron Dose: Minimizes alterations to the sample environment.
Improved Resolution: Allows for clearer images with less interference.
Controlled Kinetics: Enables manipulation of nanoparticle formation.
Real-Time Observation: Facilitates the study of dynamic processes.

A study using sub-sampling techniques to observe the nucleation and growth of silver nanoparticles provides a compelling example. In this experiment, the electron beam itself induced the reduction process, leading to particle precipitation. By segmenting the images, researchers identified three distinct types of nanoparticles: uniform nanoparticles (indicative of a homogeneous mechanism), large flat particles (heterogeneous mechanism), and sharp dendritic structures (high concentration/charge mechanisms).

The Future of Dynamic Material Studies

The findings from studies utilizing sub-sampling techniques underscore its potential in revolutionizing in-situ liquid experiments. By optimizing these methods, scientists can unlock unprecedented control over experimental conditions, paving the way for deeper insights into material behavior at the nanoscale. Future research will undoubtedly explore further refinements of sub-sampling and inpainting, expanding the scope of dynamic experiments and driving innovation in material design.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1017/s1431927618001708, Alternate LINK

Title: Using Sub-Sampling/Inpainting To Control The Kinetics And Observation Efficiency Of Dynamic Processes In Liquids

Subject: Instrumentation

Journal: Microscopy and Microanalysis

Publisher: Cambridge University Press (CUP)

Authors: N. D. Browning, B. L. Mehdi, A. Stevens, M. E. Gehm, L. Kovarik, N. Jiang, H. Mehta, A. Liyu, S. Reehl, B. Stanfill, L. Luzzi, K. Macphee, L. Bramer

Published: 2018-08-01

Everything You Need To Know

How do sub-sampling and inpainting techniques work in scanning transmission electron microscopy (STEM), and why are they significant?

Sub-sampling and inpainting techniques in scanning transmission electron microscopy (STEM) work by acquiring only a fraction of the data randomly instead of capturing every pixel. The missing information is then filled in using algorithms, related to compressive sensing. This significantly reduces the required electron dose, which minimizes beam-induced alterations to the sample. While the technique is still evolving, sub-sampled acquisitions have already shown the potential to improve dose/resolution relationships in STEM images, allowing researchers to achieve high-quality imaging during in-situ liquid experiments.

What role does high-resolution scanning transmission electron microscopy (S/TEM) play in nanomaterial synthesis, and what challenges does it address?

In the context of nanomaterial synthesis, high-resolution scanning transmission electron microscopy (S/TEM) with in-situ liquid stages allows for the direct observation of nucleation and growth phenomena. Researchers can witness material transformations under different conditions, offering previously unattainable insights. However, the electron beam used for imaging can alter the local chemistry of the solution, leading to artifacts. Sub-sampling and inpainting techniques help in bridging the gap between real-world conditions and TEM observations by minimizing electron dose and maximizing the information extracted per electron.

What insights have sub-sampling techniques provided into the nucleation and growth of nanoparticles, specifically silver nanoparticles?

Sub-sampling techniques have enabled researchers to observe and identify different types of nanoparticles formed during the reduction process induced by the electron beam. In one study, researchers identified uniform nanoparticles indicative of a homogeneous mechanism, large flat particles indicative of a heterogeneous mechanism, and sharp dendritic structures indicative of high concentration/charge mechanisms. This level of detailed observation helps in understanding the underlying processes and controlling the synthesis of nanomaterials.

What are the limitations of traditional transmission electron microscopy methods, and how does high-resolution scanning transmission electron microscopy (S/TEM) overcome these limitations?

Traditional transmission electron microscopy methods often suffer from limitations in resolution and disruptive effects due to the observation techniques themselves. This can lead to inaccurate analysis and hinder the understanding of dynamic processes in liquids. High-resolution scanning transmission electron microscopy (S/TEM) addresses these issues by using in-situ liquid stages and innovative techniques like sub-sampling and inpainting, which minimize electron dose and maximize information extraction. Further exploration into the technique could lead to a better understanding of dynamic processes.

What are the primary advantages of using sub-sampling techniques in electron microscopy, and how do these advantages contribute to advancing material science?

The key benefits of using sub-sampling techniques in electron microscopy include reduced electron dose, which minimizes alterations to the sample environment; improved resolution, allowing for clearer images with less interference; controlled kinetics, enabling manipulation of nanoparticle formation; and real-time observation, facilitating the study of dynamic processes. These benefits collectively contribute to a better understanding of material behavior at the nanoscale and drive innovation in material design. Future research will undoubtedly explore further refinements of sub-sampling and inpainting, expanding the scope of dynamic experiments.