At the beamline BL6N1 of Aichi Synchrotron Radiation Center (AichiSR), X-ray absorption and X-ray photoemission spectroscopies with the photon energy range of 1.75 – 6 keV can be carried out. In 2018, the former double-crystal monochromator has been replaced to a new one equipped with a cooling system for monochromator crystals. As a consequence, the stability of X-ray beam in terms of photon energy and intensity has been improved significantly. Taking this opportunity, the latest details of the experimental instruments of BL6N1 and the examples of the X-ray absorption and photoemission spectroscopy experiments available at BL6N1 will be presented in this article.

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ETEM is a dynamic observation technique based on transmission electron microscopy (TEM). In normal TEMs, specimens are set under vacuum condition because electron scattering by air molecules must be minimized. In contrast, ETEM enables to observe specimens immersed in gas or liquid environments. Therefore, ETEM can reveal nature of materials under the conditions in which they are formed or utilized, for example, catalysts in gas, battery electrodes in liquid electrolyte, and so on. This paper describes principles and features of two types of the ETEM, and also demonstrates effectiveness of this technique by introducing application results on gas reaction of gold nanoparticulate catalyst and high-resolution imaging in liquid environment.

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Secondary Ion Mass Spectrometry (SIMS) has been widely used in the semiconductor field, because it enables highly sensitive imaging of element distribution and depth analysis. The SIMS using MeV-energy heavy ion (MeV-SIMS) opened new possibilities for investigating chemical composition, structure as well as for imaging, which are very important for organic and biological materials. We have demonstrated molecular imaging of a rat brain with the MeV-SIMS technique. Furthermore, we have developed an atmospheric pressure SIMS technique that uses a MeV-energy ion probe, which has high transmission capability under atmospheric pressure conditions. To analyze a solid–liquid interface, the atmospheric pressure analysis system is essential, because liquid materials evaporate easily in vacuum. The volatile liquid (wet) samples, however, are difficult to measure using conventional SIMS. The mean free path of ions with energy in the keV range is very short under atmospheric pressure and these ions cannot penetrate the surface. In contrast, evaporation of liquid materials was suppressed in He at atmospheric pressure and samples containing liquid materials could be measured using the MeV-SIMS technique without dry sample preparation. Recently, we are developing a humidity controlled atmospheric pressure MeV-SIMS system, because water evaporation rate depends on the humidity strongly. In order to obtain imaging mass spectra of wet samples, it is needed to keep the wet surface of samples under ambient and humid condition for long time. In this paper, we show the results of continuous SIMS measurement of benzoic acid solution on a Si substrate in a wet He environment for solid-liquid interface analysis.

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