TY - JOUR

T1 - Single Atoms of Pt-Group Metals Stabilized by N-Doped Carbon Nanofibers for Efficient Hydrogen Production from Formic Acid

AU - Bulushev, Dmitri A.

AU - Zacharska, Monika

AU - Lisitsyn, Alexander S.

AU - Podyacheva, Olga Yu

AU - Hage, Fredrik S.

AU - Ramasse, Quentin M.

AU - Bangert, Ursel

AU - Bulusheva, Lyubov G.

PY - 2016/6/3

Y1 - 2016/6/3

N2 - Formic acid is a valuable chemical derived from biomass, as it has a high hydrogen-storage capacity and appears to be an attractive source of hydrogen for various applications. Hydrogen production via formic acid decomposition is often based on using supported catalysts with Pt-group metal nanoparticles. In the present paper, we show that the decomposition of the acid proceeds more rapidly on single metal atoms (by up to 1 order of magnitude). These atoms can be obtained by rather simple means through anchoring Pt-group metals onto mesoporous N-functionalized carbon nanofibers. A thorough evaluation of the structure of the active site by aberration-corrected scanning transmission electron microscopy (ac-STEM) in high-angle annular dark field (HAADF) mode and by CO chemisorption, X-ray photoelectron spectroscopy (XPS), and quantum-chemical calculations reveals that the metal atom is coordinated by a pair of pyridinic nitrogen atoms at the edge of graphene sheets. The chelate binding provides an ionic/electron-deficient state of these atoms that prevents their aggregation and thereby leads to an excellent stability under the reaction conditions. Catalysts with single atoms have also shown very high selectivity. Evidently, the findings can be extended to hydrogen production from other chemicals and can be helpful for improving other energy-related and environmentally benign catalytic processes.

AB - Formic acid is a valuable chemical derived from biomass, as it has a high hydrogen-storage capacity and appears to be an attractive source of hydrogen for various applications. Hydrogen production via formic acid decomposition is often based on using supported catalysts with Pt-group metal nanoparticles. In the present paper, we show that the decomposition of the acid proceeds more rapidly on single metal atoms (by up to 1 order of magnitude). These atoms can be obtained by rather simple means through anchoring Pt-group metals onto mesoporous N-functionalized carbon nanofibers. A thorough evaluation of the structure of the active site by aberration-corrected scanning transmission electron microscopy (ac-STEM) in high-angle annular dark field (HAADF) mode and by CO chemisorption, X-ray photoelectron spectroscopy (XPS), and quantum-chemical calculations reveals that the metal atom is coordinated by a pair of pyridinic nitrogen atoms at the edge of graphene sheets. The chelate binding provides an ionic/electron-deficient state of these atoms that prevents their aggregation and thereby leads to an excellent stability under the reaction conditions. Catalysts with single atoms have also shown very high selectivity. Evidently, the findings can be extended to hydrogen production from other chemicals and can be helpful for improving other energy-related and environmentally benign catalytic processes.

KW - formic acid

KW - hydrogen production

KW - nitrogen-doped carbon

KW - renewable biomass

KW - single-atom catalysts

UR - http://www.scopus.com/inward/record.url?scp=84973861656&partnerID=8YFLogxK

U2 - 10.1021/acscatal.6b00476

DO - 10.1021/acscatal.6b00476

M3 - Article

AN - SCOPUS:84973861656

VL - 6

SP - 3442

EP - 3451

JO - ACS Catalysis

JF - ACS Catalysis

SN - 2155-5435

IS - 6

ER -