Core Facility for Multidisciplinary Structural Analysis

The GZMS operates a state-of-the-art Environmental Scanning Electron Microscope (ESEM) from Thermo Fisher Scientific, which represents the central microscopy platform of the facility. The system enables high-resolution electron microscopy under variable pressure and environmental conditions, allowing the investigation of hydrated, non-conductive, beam-sensitive, and dynamic samples without extensive sample preparation. 

The Thermo Scientific™ Quattro ESEM combines conventional high-vacuum SEM performance with true environmental imaging capabilities. This allows seamless switching between high-vacuum, low-vacuum, and ESEM modes, supporting a wide range of materials and experimental workflows. 

In particular, the system enables: 

• Imaging of biological, polymeric, and soft materials in a hydrated or near-native state 
• In situ observation of mechanical deformation, fracture, and failure processes 
• Analysis of dynamic processes such as drying, swelling, or crack propagation 
• Correlative workflows combining ESEM with mechanical testing and microstructural analysis 

Due to its versatility and robustness, the ESEM is a key instrument for interdisciplinary research at the GZMS, serving users from biology, materials science, biomimetics, engineering, and geosciences. The instrument plays a central role in externally funded research projects and method development activities and represents a unique infrastructure component within the regional and national research landscape.

For quantitative mechanical characterisation at the micro- and mesoscale, the GZMS operates an in situ tensile testing system integrated into the Environmental Scanning Electron Microscope (ESEM). This setup enables controlled mechanical loading of samples while simultaneously recording high-resolution electron microscopy data under variable pressure and environmental conditions.

The facility is equipped with a Kammrath & Weiss MZ.Ms tensile module system, specifically designed for in situ mechanical experiments inside electron microscopes. The system provides precise force and displacement control and allows uniaxial tensile, compression, and cyclic loading experiments directly within the ESEM chamber.

Key capabilities include:

• In situ tensile, compression, and fatigue experiments
• Real-time observation of deformation, crack initiation, and fracture processes
• Mechanical testing of hydrated, soft, beam-sensitive, and non-conductive materials
• Quantitative correlation of stress–strain data with microstructural evolution

The MZ.Ms system is routinely used for the investigation of biological materials (e.g. insect cuticle and collagenous tissues), polymers, fibre-reinforced composites, and architected or additively manufactured structures. In combination with ESEM imaging, this setup enables experiments that directly link mechanical performance to microstructural organisation and failure mechanisms.

As part of the core instrumentation of the GZMS, the tensile module is essential for interdisciplinary research, method development, and externally funded projects addressing structure–function relationships across biological and technical materials.

A sputter coater, an essential component in electron microscopy sample preparation, plays a pivotal role in enhancing specimen conductivity and imaging quality. By employing a process known as sputtering, wherein atoms from a target material are dislodged by bombarding it with energetic ions, the sputter coater deposits a thin conductive layer onto the sample surface. This layer serves to minimize charging effects during imaging, thereby improving resolution and contrast in scanning electron microscopy (SEM) analysis. Additionally, the sputter-coated layer can enhance sample stability and reduce beam damage, particularly for non-conductive or fragile materials. With precise control over deposition parameters, such as coating thickness and material composition, the sputter coater accommodates a wide range of sample types and SEM applications. Its versatility and effectiveness make it an indispensable tool for researchers across disciplines, facilitating detailed examination and analysis of diverse specimens, from biological tissues to nanomaterials.

At the GZMS we use a state-of-the-art Leica ACE 600 system.

A critical point dryer (CPD) is renowned for its capability to gently remove solvents from delicate specimens, preserving their structural integrity during the drying process. Unlike conventional drying methods, which can cause distortion or damage to fragile samples, the CPD utilizes a combination of controlled pressure and temperature to reach the critical point of a solvent, where liquid and gas phases coexist. At this critical point, the solvent transitions directly into a gas without undergoing phase change, effectively avoiding surface tension-induced damage commonly associated with other drying techniques. This unique feature makes the CPD particularly well-suited for preparing biological samples, such as tissues or cells, as well as porous materials like ceramics or polymers, for subsequent analysis via microscopy or other analytical techniques. Its ability to provide artifact-free drying ensures accurate representation of sample morphology and composition, making the CPD an indispensable tool in various fields including materials science, biomedical research, and nanotechnology.

At the GZMS we use a state-of-the-art Leica EM CPD300 system.

The micro-computed tomography (micro-CT) scanner is a sophisticated imaging instrument renowned for its ability to produce high-resolution, three-dimensional representations of internal structures within a wide range of materials. Similar to medical CT scanners but on a much smaller scale, micro-CT utilizes X-ray technology to capture detailed cross-sectional images of specimens with micrometer-level precision. This non-destructive imaging technique allows for the visualization of internal features and spatial relationships without the need for physical sectioning or invasive procedures. From characterizing the internal morphology of biological tissues to analyzing the internal structure of engineered materials, micro-CT provides valuable insights into the microstructural properties of diverse samples. Its versatility, coupled with advanced image analysis capabilities, makes micro-CT an indispensable tool for researchers across disciplines, including materials science, biology, geology, and archaeology, facilitating a deeper understanding of complex systems and phenomena at the microscale.

At the GZMS we use a versatile Bruker Skyscan 1275 system.