Synergistic hybrid electrocatalysts of platinum alloy and single-atom platinum for an efficient and durable oxygen reduction reaction

Liu, B.*; Feng, R.*; Busch, M.*; Wang, S.*; Wu, H.*; Liu, P.*; Gu, J.*; Bahadoran, A.*; Matsumura, Daiju; Tsuji, Takuya; et al.

ACS Nano, 16(9), p.14121 - 14133, 2022/09

https://doi.org/10.1021/acsnano.2c04077

Enhancement of Fe-N-C carbon catalyst activity for the oxygen reduction reaction; Effective increment of active sites by a short and repeated heating process

Yasuda, Satoshi; Uchibori, Yosuke*; Wakeshima, Makoto*; Hinatsu, Yukio*; Ogawa, Hiroaki; Yano, Masahiro; Asaoka, Hidehito

RSC Advances (Internet), 8(66), p.37600 - 37605, 2018/11

https://doi.org/10.1039/C8RA08359B

We present a quantitative study on the effect of a newly obtained thermal history on the formation of Fe-N-C catalytic sites. A short and repeated heating process is employed as the new thermal history, where short heating (1 min) followed by quenching is applied to a sample with arbitrary repetition. Through electrochemical quantitative analysis, it is found that the new process effectively increases the Fe-N-C mass-based site density (MSD) to almost twice that achieved using a conventional continuous heating process, while the turn-over frequency (TOF) is independent of the process. Elemental analysis shows that the new process effectively suppresses the thermal desorption of Fe and N atoms during the initial formation stage and consequently contributes to an increase in the Fe-N-C site density. The resultant catalytic activity (gravimetric kinetic current density (0.8 V vs. RHE)) is 1.8 times higher than that achieved with the continuous heating process.

Effect of direct contact with iron on gas evolution behavior of aluminum

Hashizume, Shuji; Matsumoto, Junko; Bamba, Tsunetaka

Genshiryoku Bakkuendo Kenkyu, 5(1), p.45 - 49, 1998/08

http://ci.nii.ac.jp/naid/40005195032

no abstracts in English

Activity enhancement of Pt nanoparticle catalysts by the ion-irradiated carbon supports; Clarification of the interfacial structures by XAFS measurements

Kimata, Tetsuya*; Kakitani, Kenta*; Yamamoto, Shunya*; Taguchi, Tomitsugu*; Matsumura, Daiju; Shimoyama, Iwao; Iwase, Akihiro*; Kobayashi, Tomohiro*; Yamaki, Tetsuya*; Terai, Takayuki*

no journal, , 

Quite recently, the Pt nanoparticles on the Ar-ion-irradiated glassy carbon (GC) substrate have been found to exhibit high oxygen reduction reaction (ORR) activity due to electronic and structural effects through the irradiation lattice defects in the support. We performed X-ray absorption fine structure (XAFS) measurements to investigate the interface between GC and the Pt nanoparticles. The extended X-ray absorption fine structure at the Pt L edge demonstrated that the Pt-Pt bond length in the Pt nanoparticles was shorter on the Ar-ion-irradiated GC substrate than on the non-irradiated one. Therefore, the electronic interaction at the interface would modify the atomic structure of the supported Pt nanoparticles, thereby improving their ORR activity. This invited talk, called the JSAP young scientist presentation award speech, reviews what our strategy of the XAFS measurements should be for the mechanistic understanding of the GC/Pt-nanoparticle interface and enhanced ORR activity.