旭硝子財団助成研究成果報告2022

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34本田　孝志Takashi HONDA大久保貴広窒化ホウ素を基材とする小分子活性化触媒の開発Takahiro OHKUBOセレンにおけるアモルファス－結晶化過程における溶媒の極性によるキラリティ制御の解明（2019採択）Clarification of chirality control by solvent polarity in amorphous-crystallization process of selenium(Project 2019)（2019採択）Development of boron nitride catalysts for the activation of small molecules(Project 2019)24旭硝子財団　助成研究成果報告（2022）単体セレンは非晶質，単斜晶系，三方晶系といった多形を取り，近年溶媒浸漬法で溶媒極性による作り分けが報告された．しかし，溶媒がどのように構造に作用するかは未解明のままであり，結晶化の溶媒浸漬時間依存性や極性と結晶のキラリティとの相関に関する研究もない．そこで当該結晶化過程を溶媒浸漬下in-situ中性子回折実験によって，キラリティとの相関には偏光顕微鏡を用いてそれぞれ明らかにした．極性溶媒であるアセトン浸漬下では約20分後には結晶化が始まっており，約10時間後に飽和し，生成した結晶のキラリティが左巻き/右巻きでほぼ同数であることが判明した．また特定の溶媒を用いることでキラリティ制御にも成功した．Selenium has polymorphs such as amorphous, monoclinic, and trigonal structures. Recently, it has been re-ported that the solvent soaking method can produce different crystal structures depending on the solvent po-larity. However, it is still unclear how the solvent affects the structure. There are also no studies on the de-pendence of crystallization on solvent soaking time or the correlation between polarity and structural chirality. We investigated the crystallization process by in-situ neutron diffraction experiments under solvent soaking and the correlation with the chirality by a polarized light microscopy, respectively. We observed that the crystallization started after about 20 minutes of soaking in acetone, a polar solvent, saturated after about 10 hours, and that the chirality was almost the same for left-handed and right-handed crystals. We also suc-ceeded in controlling the chirality by using a specific solvent.窒素は様々な材料を創製する際の基本となる元素であるが，空気中の窒素を容易に用いることは困難で，窒素分子と強い相互作用を示す材料の創製が望まれている．本研究では，窒素分子との強い相互作用を示す材料の候補として窒化ホウ素（BN）細孔体に着目した．BNは炭素材料と等電子の関係にあるにも関わらず，炭素を基本骨格とする活性炭よりも窒素との相互作用が強いことを示す結果を得ることができた．次世代の吸着・触媒担体としてBN細孔体が有望であることを示す研究成果を得ることができた．Although nitrogen is a fundamental element for the creation of various materials, it is difficult to apply its gas-phase molecules in the air. The production of the material showing the strong interaction with the nitro-gen molecule is desired. In this study, we have focused on porous boron nitride (BN) as a candidate for mate-rials that exhibit a strong interaction with nitrogen molecules. The result showed that the interaction of porous BN with nitrogen molecules was stronger than the activated carbon whose pore wall is isoelectronic to BN. We were able to obtain research results showing the possibilities of porous BN as adsorption and catalyst car-riers for the next generation.