TY - JOUR
T1 - Effect of hydrothermal treatment temperature on the catalytic performance of single-crystalline La0.5Sr0.5MnO3-δ microcubes for the combustion of toluene
AU - Deng, Jiguang
AU - Zhang, Yue
AU - Dai, Hongxing
AU - Zhang, Lei
AU - He, Hong
AU - AU, Chak Tong
N1 - Funding Information:
This work was supported by the NSF of Beijing Municipality (Key Class B project of grant No. KZ200610005004), the SRF for ROCS (State Education Ministry of China), and the PHR (IHLB) of Beijing Municipality. CTA thanks the RGC, Hong Kong Special Administration Region for financial support (Grant no. HKBU 200106).
PY - 2008/12/15
Y1 - 2008/12/15
N2 - Perovskite-type oxide La0.5Sr0.5MnO3-δ catalysts were fabricated hydrothermally at 220, 240, 250 or 270 °C for 50 h (denoted as LSMO-220, LSMO-240, LSMO-250, and LSMO-270, respectively). We characterized the materials by a number of analytical techniques. It was found that the La0.5Sr0.5MnO3-δ samples are single-crystalline cubic perovskite-type oxides in the form of microcubes. The as-fabricated samples displayed various surface and bulk compositions that can be related to the discrepancy in treatment temperature. The surface Mn/(La + Sr + Mn) ratio and the initial H2 consumption rate at low-temperatures increase according to the sequence of LSMO-240 < LSMO-270 < LSMO-220 < LSMO-250. We observed that the surface Mn4+/Mn3+ ratio and catalytic performance of the materials follow a similar order. The temperature for 100% toluene conversion over LSMO-250 was 280 °C. The excellent performance of the materials can be related to (i) Mn surface enrichment, (ii) high Mn4+/Mn3+ ratio, (iii) oxygen nonstoichiometry, and (iv) single-crystalline structure of the catalysts.
AB - Perovskite-type oxide La0.5Sr0.5MnO3-δ catalysts were fabricated hydrothermally at 220, 240, 250 or 270 °C for 50 h (denoted as LSMO-220, LSMO-240, LSMO-250, and LSMO-270, respectively). We characterized the materials by a number of analytical techniques. It was found that the La0.5Sr0.5MnO3-δ samples are single-crystalline cubic perovskite-type oxides in the form of microcubes. The as-fabricated samples displayed various surface and bulk compositions that can be related to the discrepancy in treatment temperature. The surface Mn/(La + Sr + Mn) ratio and the initial H2 consumption rate at low-temperatures increase according to the sequence of LSMO-240 < LSMO-270 < LSMO-220 < LSMO-250. We observed that the surface Mn4+/Mn3+ ratio and catalytic performance of the materials follow a similar order. The temperature for 100% toluene conversion over LSMO-250 was 280 °C. The excellent performance of the materials can be related to (i) Mn surface enrichment, (ii) high Mn4+/Mn3+ ratio, (iii) oxygen nonstoichiometry, and (iv) single-crystalline structure of the catalysts.
KW - Hydrothermal synthesis
KW - Microcube
KW - Single-crystalline perovskite-type oxide
KW - Toluene oxidation
KW - Volatile organic compounds
UR - http://www.scopus.com/inward/record.url?scp=54849432728&partnerID=8YFLogxK
U2 - 10.1016/j.cattod.2008.08.010
DO - 10.1016/j.cattod.2008.08.010
M3 - Article
AN - SCOPUS:54849432728
SN - 0920-5861
VL - 139
SP - 82
EP - 87
JO - Catalysis Today
JF - Catalysis Today
IS - 1-2
ER -