【公開日：2024.07.25】【最終更新日：2024.05.17】

課題データ / Project Data

課題番号 / Project Issue Number

23NM0149

利用課題名 / Title

ディーゼル触媒の粒子構造の解析

利用した実施機関 / Support Institute

物質・材料研究機構 / NIMS

機関外・機関内の利用 / External or Internal Use

外部利用/External Use

技術領域 / Technology Area

【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-

【重要技術領域 / Important Technology Area】（主 / Main）マテリアルの高度循環のための技術/Advanced materials recycling technologies（副 / Sub）-

キーワード / Keywords

透過型電子顕微鏡,触媒,Pt

利用者と利用形態 / User and Support Type

利用者名（課題申請者）/ User Name (Project Applicant)

マン レニー

所属名 / Affiliation

株式会社中化学日本総合研究所

共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes

ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes

利用形態 / Support Type

（主 / Main）機器利用/Equipment Utilization（副 / Sub）-

利用した主な設備 / Equipment Used in This Project

NM-503：200kV電界放出形透過電子顕微鏡（JEM-2100F1）
NM-504：200kV電界放出形透過電子顕微鏡（JEM-2100F2）
NM-505：200kV透過電子顕微鏡
NM-516：TEM試料作製装置群

報告書データ / Report

概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)

Understanding changes in catalysts on a nanoscale level is crucial in catalyst development, as minuscule changes may translate to drastic differences in catalyst performance, stability, and durability. Using TEM, we aim to learn new structural information about our catalysts, especially key components such as alumina, Pt, Pd, or other species. This will provide new insight into our processes, expand our understanding of the process, and facilitate improvements in future generations of our catalysts.

実験 / Experimental

TEM sample grids were prepared before the experiment. The samples were observed using transmission electron microscope (TEM) at 200 kV, using one of JEM-2100, JEM-2100F1, or JEM-2100F2. Electron dispersive spectroscopy (EDS) was performed on one sample. When necessary, carbon coater (JEC-560) was used to prevent sample degradation during data collection.

結果と考察 / Results and Discussion

Two samples containing a low amount of precious metal (platinum) on alumina were examined using TEM. Under TEM mode, irregular rod-like structures, presumably alumina, were observed in sample 1 (Figure 1). Locations of Pt nanoparticles were unclear due to overlaps of alumina particles, creating a darker contrast that resembles Pt particles. Switching to STEM mode then allows identification of the Pt nanoparticles from the larger alumina nanoparticles present, simply with the contrast. This was then confirmed with EDS, with element mapping of Pt confirming well-dispersed Pt nanoparticles (~5 nm) throughout the sample. Oxygen mapping indicated that these particles are likely in an oxidized state, i.e. PtO₂.

On the other hand, sample 2 (prepared in a different condition than sample 1) had few Pt nanoparticles present in the matrix of rod-like alumina particles (Figure 2). The Pt particles found were all large, in the range of 20-30 nm. Some particles measured up to 34.6 nm in one dimension, with crystalline reflections seen. As these particles were large, EDS was not needed to correctly differentiate between Pt and alumina particles. The crystallinity of the sample was confirmed when taking a closer view at high resolution, showing the d-spacing of the plane. Fast Fourier transform (FFT) then revealed a d-spacing of 0.27 nm, which agrees with the known d-spacing of PtO₂. While the samples looked similar to the naked eye, the particle sizes were drastically different and should show different catalytic activities when tested.

図・表・数式 / Figures, Tables and Equations

TEM and STEM images of sample 1.

TEM images of sample 2.

その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)

成果発表・成果利用 / Publication and Patents

論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)

口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.

特許 / Patents

特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件