Expanding accessible 3D sample size in lab-based X-ray nanotomography without compromising resolution

Abstract

State-of-the-art lab-based X-ray nanotomography enables versatile and well-accessible three-dimensional imaging of samples with spatial resolutions comparable to synchrotron setups. By its nature, the technique brings a trade-off between high spatial resolution and accessible sample volume. A so-called ‘stitching approach’ can overcome this challenge by extending the accessible three-dimensional volume without compromising spatial resolution and is demonstrated in a state-of-the-art lab-based X-ray microscope on two porous, low-Z material systems: macroporous zeolite particles and supported catalytically active metal solutions. Fourier ring and shell correlation are utilized to calculate the achievable two- and three-dimensional resolution of the X-ray microscope and the tomographic reconstructions, respectively. The excellent performance of the stitching approach is evaluated by comparing three-dimensional reconstructions of identical sample volumes obtained with and without stitching at different magnifications. The influence of illumination time, depth of field and number of projections are investigated by comparing the spatial resolution of the experiments with theoretical resolution limits.