Advanced neutron diffraction and imaging high-throughput characterization technology based on China Spallation Neutron Source General Purpose Powder Diffractometer
Lunhua He
1Institute of Physics, Chinese Academy of Sciences, Beijing, 100190
2Spallation Neutron Source Science Center, Dongguan, 523803

EXTENDED ABSTRACT: The General Purpose Powder Diffractometer (GPPD) is one of the first three spectrometers built by China's Spallation Neutron Source (CSNS). It is mainly used to study the crystal structure and magnetic structure of substances to meet the requirements of the needs of scientific research and industrial applications in many fields such as materials science, nanoscience, condensed matter physics and chemistry. Since September 2018, GPPD has been officially opened to users. Up to now, GPPD has successfully completed more than 100 user research projects, with more than 10,000 operating hours. The users of GPPD have achieved important experimental results in many research fields, including steel, magnetic materials, energy materials, and functional materials. In just three years of commissioning and operation, more than 50 SCI research papers, including Science, Nature Communications, Advanced Materials, etc。

With the development of science, material genetic engineering has raised the need for high-throughput characterization. Targeted research and development of technological devices that match the advanced neutron source, fully tap the potential of large scientific devices in high-throughput characterization, and give play to the strong complementarity between the advanced neutron source and other light source characterization capabilities to form a more comprehensive characterization platform. This is of special significance for China to build a world-leading high-throughput experimental platform based on large scientific devices. We developed the neutron beam KB focusing technology to optimize the focus Components, realize millimeter-level beam spot, increase the neutron flux at the sample, and greatly shorten the characterization time. We have also developed a neutron imaging system and completed the first Bragg-edge neutron imaging experiment in China, enabling the diffraction platform to have imaging capabilities and achieve micron-level spatial resolution. Without changing the structure of the spectrometer, GPPD was transformed into a high-throughput characterization experimental station suitable for combined material samples, making it the first spectrometer with diffraction + imaging mode, as shown in Figure 1. This provides new methods, new technologies, and new devices for conducting small-scale sample scattering experiments based on existing neutron sources, expands the application scope of advanced neutron sources such as CSNS, and supports the development of relevant cutting-edge scientific research in China。