S. Wannaparhun et al /Applied Surface Science 185(2002)183-196 187 Table 1 analysis of the as-received mullite, Nextel-720 fiber, alumina matrix, and composite Material SU/Al Spectrum Peak fitted data BE(ev) FWHM (e Percentage of area Phase [51] mullite Aluminosilicate Si(2p) 1028 Aluminosilicate Aluminosilicate Nextel-720 fiber 0.3208 73.5 Aluminum oxide Si(2p) 101.8 117 Aluminum oxide 31.1 88.3 Aluminosilicate Alumina matrix 0.0302 A(2p) 937 Aluminum oxide 1.66 Aluminosilicate S 1017 142 00 Aluminosilicate 530.3 2.0 Aluminum oxide 317 10.9 Aluminosilicate omposite A(2p) 73.6 88.2 118 S 101.5 530.1 2.05 71.9 5312 3.1.1.2. XPS Si(2p). Fig 5a indicates a left shoulder of the deconvoluted peak(101.7 eV, Table 1)and the of Al(2s)peak around 115 eV. The first and the second literature(102.6eV [51) can be explained based on satellite of Al(2s)are located at 110 and 95-105 e V, the IC effect [50] mentioned earlier. At very low Si/Al respectively. In Fig 6a, the deconvoluted Si(2p)peak ratio, the Si(2p)peak should be located at a low BE was found embedding in the range of the Al(2s)'s position. In this case, the Si/Al ratio was very low such second satellite. The discrepancy between the position that the Si(2p)peak could not be observed in the Mullite 115 Fig.5. XPS Si(2p,) spectrum of the as-received: (a)alumina matrix:(b)mullite(* denotes first satellite of Al(2s)3.1.1.2. XPS Si(2p3 ). Fig. 5a indicates a left shoulder of Al(2s) peak around 115 eV. The first and the second satellite of Al(2s) are located at 110 and 95–105 eV, respectively. In Fig. 6a, the deconvoluted Si(2p3 ) peak was found embedding in the range of the Al(2s)’s second satellite. The discrepancy between the position of the deconvoluted peak (101.7 eV, Table 1) and the literature (102.6 eV [51]) can be explained based on the IC effect [50] mentioned earlier. At very low Si/Al ratio, the Si(2p3 ) peak should be located at a low BE position. In this case, the Si/Al ratio was very low such that the Si(2p3 ) peak could not be observed in the Table 1 XPS analysis of the as-received mullite, Nextel-720 fiber, alumina matrix, and composite Material Si/Al Spectrum Peak fitted data BE (eV) FWHM (eV) Percentage of area Phase [51] Mullite 0.5158 Al(2p) 74.9 1.91 100 Aluminosilicate Si(2p3 ) 102.8 1.96 100 Aluminosilicate O(1s) 531.7 2.58 100 Aluminosilicate Nextel-720 fiber 0.3208 Al(2p) 73.5 2.09 15 Aluminum oxide 74.2 2.09 85 Aluminosilicate Si(2p3 ) 101.8 1.84 100 Aluminosilicate O(1s) 530.8 2.54 11.7 Aluminum oxide 531.1 2.54 88.3 Aluminosilicate Alumina matrix 0.0302 Al(2p) 73.6 1.66 93.7 Aluminum oxide 74.6 1.66 6.3 Aluminosilicate Si(2p3 ) 101.7 1.42 100 Aluminosilicate O(1s) 530.3 2.07 89.1 Aluminum oxide 531.7 2.07 10.9 Aluminosilicate Composite 0.0622 Al(2p) 73.6 1.64 88.2 Aluminum oxide 74.2 1.64 11.8 Aluminosilicate Si(2p3 ) 101.5 1.98 100 Aluminosilicate O(1s) 530.1 2.05 71.9 Aluminum oxide 531.2 2.05 28.13 Aluminosilicate Fig. 5. XPS Si(2p3 ) spectrum of the as-received: (a) alumina matrix; (b) mullite ( denotes first satellite of Al(2s)). S. Wannaparhun et al. / Applied Surface Science 185 (2002) 183–196 187