Time resolved powder diffraction technique under gas atmosphere for revealing the nanopore structure

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K18310
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 80040:Quantum beam science-related
• Research Institution: Japan Synchrotron Radiation Research Institute
• Principal Investigator: Kawaguchi Shogo 公益財団法人高輝度光科学研究センター, 回折・散乱推進室, 研究員 (10749972)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: その場構造計測 / 時間分解計測 / 放射光粉末X線回折 / ガス雰囲気下

Outline of Final Research Achievements

In this study, in order to clarify change of crystal structure such as metal-organic complex and zeolite under the gas adsorption/desorption process, we developed a gas pressure control system synchronized with fast continuous powder diffraction experiment using the high energy synchrotron X-rays beam. We have performed time-resolved synchrotron powder diffraction experiment for metal-organic Framework compound using developed gas handling system. The changes of guest structure under gas adsorption/desorption were observed, and it was clarified that the desorption phase changed to the adsorption phase within a few seconds. The rate of change depends on the pressure of gas introduction. We systematically examined the relation between pressure and rate, we succeeded in estimating the rate constant during gas adsorption. Thus, by this project, a method for time-resolved powder structure measurement under gas pressure control was established.

Free Research Field

放射光X線回折

Academic Significance and Societal Importance of the Research Achievements

本課題の放射光を用いた時間分解粉末構造計測システムは、平衡状態以外の吸着/脱着プロセスの結晶構造の変化を観測することが可能となり、ガス吸着や脱着に関わるメカニズムの理解と、ガス貯蔵、ガス分離、触媒反応のための機能性材料の合成設計指針に重要な情報が得られる期待される。さらに、本計測装置は溶媒蒸気や水蒸気にも対応可能であるため環境科学技術への応用も可能であり、本装置を活用することにより様々な機能性材料における水処理や有害気体物質や温室効果ガスなどの分離・貯蔵技術の効率向上にも期待される。