The power of CeO2
precipitate was filtered, washed thrice with distilled
technology of direct precipitation water and alcohol and dried at
Results and discussion
(a)
(b)
(c)
(d)
SEM photoes of precursor
(a): Ce(NO3)3 + NH3·H2O
(b):
(NH4)2Ce(NO3)6
+
NH3·H2O
(c): Ce(NO3)3 + NH4HCO3
(d): (NH4)2Ce(NO3)6 + NH4HCO3
(d)
(c)
(b)
(a)
10
CeO2 Slurry
氧化铈抛光粉
氧化铈抛光轮
玻璃脱色剂氧化铈
大颗粒氧化铈磨料 氧化铈抛光粉/液晶显示屏
此外， CeO2还用作催化材料、高温氧敏材料、 pH传感材料、电化学池中膜反 应器材料、燃料电池的中间材料、中温固体氧化物燃料电池(SOFC)用电极材料
Synthesis of
1. Direct
CeO2
precipitCaet3+ioornCe4+
precipitant
precipitation
Stir and ageing stage
Nitrate: Ce(NO3)3 or (PNrHe4c)2iCpei(NtOa3n)t6 : ammonia or NH4HCO3
Surface active agent: PEG4P0r0o0cess: nitrate and PEG-4000
1.Simply introduce the structure and applications of CeO2
2. Synthesis of nanocrystalline CeO2 by different methods
3. Future works
Brief introduction
1. Structure of CeO2
Microwave reaction equipment
CO(NH2)2 + H2O → CO2 + 2NH3 NH3 + H2O → NH4+ + OHCO2 + H2O → CO32- + 2H+
水解生成的构晶 离子OH-、CO32-, 在微波辐照作用 下,与Ce3+、Ce4+ 等结合生成不溶 前驱物
Members: Xianhong Rui Yu Chen Litao Yan Huamin Yao Liangjun Yi
Department of Materials Science and Engineering University of Science and Technology of China Jan 3, 2008
LS of CeO2 calcined at 600℃
(a) Ce(NO3)3 + urea, without PEG4000 (b) Ce(NO3)3 + urea + PEG-4000 (c) (NH4)2Ce(NO3)6 + urea + PEG-4000
2000 1500
700℃
1000 500
Results and discussion
(c) (b)
Mean: (a)0.093um (b)0.171um (c)0.210um
(a)
10
20
30
40
50
60
70250ຫໍສະໝຸດ XRDof2
precursor calcined
at
500℃
200
150
100
50
0
10
20
30
40
50
60
70
XRD of2precursor (a)
20
30
40
50
60
70
2
XRD of precursor
(d) (c)
(c)
(a) (b)
10
20
30
40
50
60
70
2
XRD of CeO2 synthesized at 600℃
(a)
3000
2500
10
20
30
40
50
60
70
2000
(c)

XRD of CeO2 synthesized at 500℃
值得注意的是，即使从晶格上失去相当数 量的氧，形成大量氧空位之后，CeO2仍然能保持 萤石型晶体结构，这种亚稳氧化物暴露于氧化环 境时又易被氧化为CeO2，因而CeO2具有优越的储 存和释放氧功能及氧化还原反应能力，同时CeO2 也有着良好的化学稳定性和高温快速氧空位扩散 能力。
Applications of CeO2
CeO2属于萤石型氧化物。 CeO2晶胞中的Ce4+按面心立 方点阵排列，O2-占据所有 的四面体位置，每个Ce4+被 8个O2-包围，而每个O2-则与 4个Ce4+配位。
2.功能特性
CeO2的结构中有1/2立方体空隙，可称之为 敞型结构。敞型结构允许离子快速扩散。经高温 (T＞950℃)还原后，CeO2转化为具有氧空位、非 化学计量比的CeO2-X氧化物(0<x<0.5)，而在低温 下(T＜450℃) CeO2可形成一系列组成各异的化合 物。
were dissolved in distilled
Scouring and drying
wate.Then ammonia or NH4HCO3 solution was added dropwise
to calcine precursor
under vigorous stirring till the pH reached 9. The
600℃
0
10
20
30
40
50
60
70
2
XRD of CeO2 synthesized at 600℃、700℃
SEM photo of precursor(a)
1500
1000
(a)
500
0
10
20
30
40
50
60
70
2
XRD of CeO2 synthesized at 700℃
(a)
(c)
SEM photoes of CeO2 calcined at 600℃
Microwave homogeneous precipitation
Nitrate: Ce(NO3)3 or (NH4)2Ce(NO3)6 Precipitant: urea Surface active agent: PEG4000