Shape-selective synthesis, magnetic properties, and catalytic activity of single crystalline β-MnO2 nanoparticles

被引:94
作者
Jana, Subhra [1 ]
Basu, Soumen [1 ]
Pande, Surojit [1 ]
Ghosh, Suffit Kumar [1 ]
Pal, Tarasankar [1 ]
机构
[1] Indian Inst Technol, Dept Chem, Kharagpur 721302, W Bengal, India
关键词
D O I
10.1021/jp074803l
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The shape-controlled synthesis of exclusively single crystalline beta-MnO2, nanospheres on one hand and nanorods on the other, has been achieved through air oxidation of MnCl2 in variable SDBS micellar templates under alkaline condition at room temperature. Raman measurement and TEM unequivocally confirm the changes in the structural aspects of the particles from sphere to rod. Field-dependent magnetization measurement indicates superparamagnetic nature of MnO2 rods and spheres having a blocking temperature of 4 and 40 K, respectively. These observations together with other physical parameters explicitly confirm the changes in the structural aspects of the particles with the changes in surfactant concentration. Thus, nanorods of high aspect ratio (similar to 25) were obtained exclusively leaving aside the embryonic spherical particles (5 +/- 2 nm) at lower surfactant concentration. This Article also focuses for the first time on the change in magnetic properties and cyclic voltammograms when we enroute nanospheres to nanorods. The catalytic activity of spherical and rod shaped particles has also been demonstrated.
引用
收藏
页码:16272 / 16277
页数:6
相关论文
共 38 条
[1]   Surface properties of sol-gel synthesized δ-MnO2 as assessed by N2 sorptometry, electron microscopy, and X-ray photoelectron spectroscopy [J].
AL-Sagheer, FA ;
Zaki, MI .
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, 2000, 173 (1-3) :193-204
[2]   MAGNETIC-PROPERTIES OF SUBMICRONIC ALPHA-FE2O3 PARTICLES OF UNIFORM SIZE DISTRIBUTION AT 300-K [J].
AMIN, N ;
ARAJS, S ;
MATIJEVIC, E .
PHYSICA STATUS SOLIDI A-APPLIED RESEARCH, 1987, 104 (01) :K65-K68
[3]   ELECTROCHROMIC REACTIONS IN MANGANESE OXIDES .1. RAMAN ANALYSIS [J].
BERNARD, MC ;
GOFF, AHL ;
THI, BV ;
DETORRESI, SC .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1993, 140 (11) :3065-3070
[4]   Semiconductor nanocrystals as fluorescent biological labels [J].
Bruchez, M ;
Moronne, M ;
Gin, P ;
Weiss, S ;
Alivisatos, AP .
SCIENCE, 1998, 281 (5385) :2013-2016
[5]   Vibrational spectroscopy of bulk and supported manganese oxides [J].
Buciuman, F ;
Patcas, F ;
Craciun, R ;
Zahn, DRT .
PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 1999, 1 (01) :185-190
[6]   Chemistry and properties of nanocrystals of different shapes [J].
Burda, C ;
Chen, XB ;
Narayanan, R ;
El-Sayed, MA .
CHEMICAL REVIEWS, 2005, 105 (04) :1025-1102
[7]  
DRAVID VP, 2005, NANOSPACE, V2, P67
[8]   Indium phosphide nanowires as building blocks for nanoscale electronic and optoelectronic devices [J].
Duan, XF ;
Huang, Y ;
Cui, Y ;
Wang, JF ;
Lieber, CM .
NATURE, 2001, 409 (6816) :66-69
[9]  
Dumestre F, 2002, ANGEW CHEM INT EDIT, V41, P4286, DOI 10.1002/1521-3773(20021115)41:22<4286::AID-ANIE4286>3.0.CO
[10]  
2-M