e-journal

One-step synthesis of nanostructured Pd-doped mixed oxides MOx-CeO2 (M = Mn, Fe, Co, Ni, Cu) for efficient CO and C3H8 total oxidation

---

Abstract.
A series of nanostructured Pd-doped mixed oxides MOx-CeO2 (M = Mn, Fe, Co, Ni, Cu), with uniform
mesoporous structure and large surface area exceeding 115 m2 g-1, were synthesized in one step by a
surfactant-assisted co-precipitation. Their catalytic performance was investigated using total oxidation
of CO and C3H8 as the model reactions. The results show that, a synergism exists between even trace
amounts of exposed Pd and 3d-transition metal oxides for CO oxidation, whereas such an effect is absent
for C3H8 oxidation. In situ diffuse reflectance infrared spectroscopy (DRIFTS) study reveals that the
synergistic essential for CO oxidation should be the interaction-assisted generation of active oxygen
species between Pd and MOx, which react readily with CO, forming bidentate carbonate (1587 and
1285 cm1) as intermediates. Moreover, structural characterization results indicate that a solid solution
is formed between CeO2 and Mn2O3 or Fe2O3, resulting in the very strong interaction between Pd and
MOx, as well as the greatly improved CO oxidation. The light-off temperatures for Pd-doped Mn and Fecontaining catalysts, as compared with the Pd-free catalysts, are decreased by more than 70 and 100 oC,
respectively. In particular, a CO conversion as high as 80% can be achieved even at room temperature on
Pd-doped Mn-containing catalyst. While for C3H8 oxidation, the C–H bond activation, but not the oxygen
activation, plays a crucial role. The C–H bond activation ability of the catalysts is largely determined by
the d-electron configurations of the M cations. A ‘double-peak’ phenomenon can be derived with the
increase of d-electron number.

Keywords: Palladium, Ceria, CO oxidation, Propane oxidation, Synergism, Mechanism

---

Ketersediaan

Tidak ada salinan data

Informasi Detail

Judul Seri

Applied Catalysis B: Environmental

No. Panggil

-

Penerbit

London : Elsevier B.V.., 2009

Deskripsi Fisik

Applied Catalysis B: Environmental 87 (2009) 92–103

Bahasa

English

ISBN/ISSN

-

Klasifikasi

-

Tipe Isi

-

Tipe Media

-

Tipe Pembawa

-

Edisi

-

Subjek

KIMIA

Info Detail Spesifik

-

Pernyataan Tanggungjawab

agus

Versi lain/terkait

Lampiran Berkas

Komentar

---

Anda harus masuk sebelum memberikan komentar