{"id":22359,"date":"2019-05-20T10:14:05","date_gmt":"2019-05-20T02:14:05","guid":{"rendered":"https:\/\/www.kuaiqikan.com\/?p=22359"},"modified":"2019-05-20T10:14:05","modified_gmt":"2019-05-20T02:14:05","slug":"sci-lun-wen-zhong-ru-he-miao-shu-raman-de-shi-yan-jie-guo","status":"publish","type":"post","link":"https:\/\/www.kuaiqikan.com\/sci-lun-wen-zhong-ru-he-miao-shu-raman-de-shi-yan-jie-guo\/","title":{"rendered":"SCI\u8bba\u6587\u4e2d\u5982\u4f55\u63cf\u8ff0Raman\u7684\u5b9e\u9a8c\u7ed3\u679c\uff1f"},"content":{"rendered":"

\u64b0\u6587\uff1a\u738b\u6d77\u71d5 \u00a0\u6240\u5c5e\u4e13\u680f\uff1aSCI\u8bba\u6587\u5199\u4f5c\u5b9e\u9a8c\u5ba4<\/span><\/p>\n

\u524d\u8a00\uff1a<\/strong><\/p>\n

\u5df2\u7ecf\u5f88\u957f\u65f6\u95f4\u6ca1\u6709\u66f4\u65b0\u201c\u7ec6\u8bf4\u8868\u5f81\u201d\u680f\u76ee\u4e86\uff0c\u4eca\u5929\u6765\u8ddf\u5927\u5bb6\u5206\u4eab\u4e00\u4e0bRaman\u7684\u5177\u4f53\u5199\u6cd5\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u6709\u6240\u5e2e\u52a9\uff01\u6309\u7167\u60ef\u4f8b\uff0c\u84dd\u8272\u5b57\u4f53<\/strong>\u90e8\u5206\u4e3a\u6a21\u677f\u3002<\/p>\n

1.\u00a0\u00a0\u5982\u4f55\u975e\u5e38\u8be6\u7ec6\u5730\u63cf\u8ff0Raman\u7684\u5b9e\u9a8c\u7ed3\u679c\uff1f<\/strong><\/p>\n

\u4e3e\u4f8b\uff1a<\/strong>In order to obtain better confirmation on the presence of\u00a0H4<\/sub>SiMo12<\/sub>O40<\/sub>,\u00a0Raman spectroscopic investigation was also conducted,\u00a0because Raman spectroscopy is a sensitive technique to study supported metal oxide and it is complementary to\u00a0IR\u00a0investigation.\u00a0The Raman spectra of\u00a0the MoVI<\/sup>@mSiO2<\/sub>\u00a0and its derived\u00a0H4<\/sub>SiMo12<\/sub>O40<\/sub>@mSiO2\u00a0<\/sub>hollow spheres\u00a0are displayed in\u00a0Figure 8, with reference to those of\u00a0pure mesoporous silica and commercial \u03b1-MoO3<\/sub>.\u00a0For\u00a0pure mesoporous silica,\u00a0the peak at\u00a0984 cm\u22121\u00a0<\/sup>is attributed to stretching vibration of\u00a0Si\u2212OH\u00a0bond and the peak at\u00a0821 cm\u22121<\/sup>\u00a0to\u00a0Si\u2212O\u2212Si\u00a0linkages, while the two peaks at\u00a0648 and 487 cm\u22121<\/sup>\u00a0are assigned to the presence of\u00a0siloxane rings.\u00a0Indeed, apart from the\u00a0488 cm\u22121<\/sup>\u00a0peak, there are four new peaks observed for the\u00a0MoVI<\/sup>@mSiO2<\/sub>-20\u00a0sample in\u00a0Figure 8a,which are characteristic of\u00a0heptamolybdate species (Mo7<\/sub>O2<\/sub>46\u2212<\/sup>).\u00a0The peaks at\u00a0952 and 878 cm\u22121<\/sup>\u00a0are due to symmetric and asymmetric stretching of the\u00a0terminal Mo=O\u00a0bond, while the peaks at\u00a0374 and 223 cm\u22121<\/sup>\u00a0are attributable to bending vibration of\u00a0terminal Mo=O\u00a0and deformation of\u00a0Mo\u2212O\u2212Mo\u00a0respectively.\u00a0It is noted that no peaks corresponding to the\u00a0MoO3<\/sub>phase were observed, which indicates\u00a0that the present thermal infusion method is effective to prepare highly dispersed molybdenum oxide within the mesoporous silica spheres.\u00a0Afterthe hydration of MoVI<\/sup>@mSiO2<\/sub>\u00a0with water,\u00a0more Raman peaks appeared due to restructuring of\u00a0surface heptamolybdate species.\u00a0The peaks at\u00a0998\u2212999,977\u2212981, 910\u2212913, 789, 645, and 247 cm\u22121<\/sup>\u00a0can be unambiguously assigned to\u00a0silicomolybdic acid, though it is still difficult to differentiate between the \u03b1 and \u03b2 forms of this solid acid (Figure 8b,c).\u00a0In addition to those of\u00a0silicomolybdic acid,\u00a0the peaks at\u00a0818, 367 and 214\u2212217, and 155 cm\u22121<\/sup>\u00a0are also observed; these peaks could be attributed to the presence of\u00a0the \u03b1-MoO3<\/sub>\u00a0phase. Quite clearly, water could also facilitate the crystallization of surface heptamolybdate species to small \u03b1-MoO3\u00a0<\/sub>clusters, which probably took place during the drying process (100 \u00b0C).\u00a0The above observation is also consistent with\u00a0our FT-IR\u00a0findings, revealing that silicomolybdic acid is responsible for the high activity observed for the Friedel\u2212 Crafts alkylation.<\/p>\n

\u53c2\u8003\u6587\u732e\uff1a<\/strong>Zeng H. et al., J. Am. Chem. Soc. 2012, 134,16235\u221216246.<\/p>\n

\u63d0\u70bc\u8bed\u8a00\u6a21\u677f\uff1a<\/strong><\/p>\n

\u4e3a\u4ec0\u4e48\u8981\u505a\u8fd9\u4e2a\u8868\u5f81\uff1aIn order to obtain better confirmationon the presence of\u00a0\u7269\u79cd\u7c7b\u578b, Raman spectroscopic investigation was also conducted.<\/p>\n

\u5f97\u5230\u54ea\u4e9b\u4fe1\u606f\uff0c\u8bf4\u660e\u4e86\u4ec0\u4e48\u95ee\u9898\uff1aFor\u00a0\u7269\u79cd\u7c7b\u578b,\u00a0the peaks at\u00a0\u5cf0\u4f4d\u7f6e\u00a0are attributable to\/are attributed to\/can be assigned to the symmetric and asymmetric stretching of\u00a0\u952e\u578b\u00a0bond\/the bending vibration of\u00a0\u952e\u578b\u00a0and deformation of\u00a0\u952e\u578b,\u00a0respectively.<\/p>\n

The peaks at\u00a0\u5cf0\u4f4d\u7f6e\u00a0are also observed, which could be attributed to\/could be assigned to the presence of \/are characteristic of \/correspondswell with\u00a0\u7269\u79cd\u7c7b\u578b.<\/p>\n

It is noted that no peaks corresponding to the\u00a0\u7269\u79cd\u7c7b\u578b\u00a0were observed, which indicates<\/p>\n

\u4ece\u8fd9\u4e9b\u4fe1\u606f\u8fd8\u53ef\u4ee5\u8fdb\u4e00\u6b65\u5f97\u5230\u4ec0\u4e48\uff1aThe above observation is also consistent with\u00a0\u5176\u4ed6\u8868\u5f81\u624b\u6bb5findings, revealing that…<\/p>\n

2. \u7531\u4e8eRaman\u5149\u8c31\u5728\u4e0d\u540c\u6587\u7ae0\u60f3\u8981\u8868\u8fbe\u7684\u89c2\u70b9\u4e0d\u540c\uff0c\u4e0d\u540c\u6587\u7ae0\u7684\u63cf\u8ff0\u7ed3\u679c\u53ef\u80fd\u7565\u6709\u4e0d\u540c\u3002\u4e0b\u9762\u603b\u7ed3\u4e00\u4e9b\u6bd4\u8f83\u5e38\u89c1\u7684\u5199\u6cd5\u4f9b\u5927\u5bb6\u53c2\u8003\u3002<\/strong><\/p>\n

A.\u00a0\u6307\u6d3e\u578b<\/strong><\/p>\n

Evidently, this spectrum has all the characteristics of\u00a0an amorphous tungsten oxide (a-WO3<\/sub>),namely all bands are broad and their relative band intensities are characteristic of\u00a0a<\/em>-WO3<\/sub>.The band at\u00a0around 960 cm-1<\/sup>\u00a0again\u00a0can be assigned to\u00a0the terminal W=O\u00a0stretching mode, possibly on the surface of the cluster and in microvoid structures in the film.\u00a0The broad band centered at\u00a0760 cm-1<\/sup>\u00a0most probably can be deconvoluted into several Raman peaks, including the strongest peaks\u00a0at\u00a0715 and 807 cm-1\u00a0<\/sup>of\u00a0a monoclinic WO3.<\/p>\n

\u53c2\u8003\u6587\u732e\uff1a<\/strong>Augustynski J.,\u00a0J. Am. Chem. Soc.,\u00a0<\/em>2001,\u00a0123,\u00a0<\/em>10639-10649.<\/p>\n

B. \u00a0Raman\u4f5c\u4e3a\u4f50\u8bc1\u624b\u6bb5<\/strong><\/p>\n

Raman\u4f5c\u4e3a\u4f50\u8bc1\u624b\u6bb5\uff0c\u901a\u5e38\u5173\u6ce8\u5cf0\u7684\u6709\u65e0,\u5cf0\u5f3a\u5ea6\u548c\u5cf0\u4f4d\u7f6e\u7684\u53d8\u5316\u3002<\/p>\n

1) \u5cf0\u7684\u6709\u65e0,\u5cf0\u5f3a\u5ea6\u7684\u53d8\u5316<\/p>\n

UV Raman spectra of these samples indicate that\u00a0the mixed phases of\u00a0anatase and rutile coexist\u00a0in the surface region.\u00a0Namely, when the TiO2\u00a0<\/sub>sample is calcined at 700\u2013 750\u00a0o<\/sup>C,\u00a0the phase junctions between\u00a0anatase and rutile\u00a0are derived on the surface of\u00a0the rutile TiO2<\/sub>,\u00a0as characterized by\u00a0UV Raman spectroscopy\u00a0combined with\u00a0XRD and visible Raman spectroscopy.<\/p>\n

\u53c2\u8003\u6587\u732e:<\/strong>\u00a0Li C., Angew. Chem. Int. Ed. 2008, 47, 1766\u20131769.<\/p>\n

Raman spectroscopy has proven to be a powerful, local structural probe for\u00a0MnO2<\/sub>.\u03b4-phase MnO2\u00a0<\/sub>has strong Raman-active\u00a0(Mn-O)\u00a0stretching transitions at\u00a0646 and 575 cm-1<\/sup>.\u00a0A somewhat weaker transition at\u00a0510 cm-1\u00a0<\/sup>is also prominent but less intense in\u00a0most \u03b4-phase MnO2<\/sub>\u00a0samples.\u00a0All three of these characteristic Raman peaks are observed for\u00a0MnO2<\/sub>\u00a0films prepared using the multipulse procedure (Figure 5b),\u00a0whereas\u00a0a mp-MnO2\u00a0<\/sub>nanowire prepared by multipulse deposition on quartz\u00a0exhibits two of these at\u00a0656 and 568 cm-1<\/sup>.Peaks at lower energies, including the\u00a0510 cm-1\u00a0<\/sup>mode, cannot be observed\u00a0because this spectral region is obscured by transitions of the quartz surface.\u00a0Collectively the data of\u00a0Figure 5suggests that the\u00a0mp-MnO2<\/sub>\u00a0nanowires\u00a0have some\u00a0birnessite\u00a0character\u00a0despite being X-ray amorphous.<\/p>\n

\u53c2\u8003\u6587\u732e\uff1a<\/strong>Penner Reginald M. et al., ACS nano, 2011, 5,8275\u20138287.<\/p>\n

2)\u00a0\u5cf0\u5f3a\u5ea6\u548c\u4f4d\u7f6e\u7684\u53d8\u5316<\/strong><\/p>\n

The agglomeration of graphene sheets is also confirmed with Raman spectroscopy as shown in\u00a0Fig. 4.\u00a0The D band of our sample is relatively intense compared to the G band, which is in agreement with\u00a0previous results for graphene samples obtained from exfoliated GO. It was shown that alongthe graphite\u2192GOreduced<\/sub>\u2192GO path the Raman spectra undergo significant changes. Specifically,\u00a0the\u00a0G band\u00a0broadened significantly and displayed a shift to higher frequencies (blue-shift),and the\u00a0D band\u00a0grew in intensity.\u00a0The Raman spectrum of our sample contains\u00a0a G band at 1584 cm-1<\/sup>, a D band at 1352 cm-1<\/sup>\u00a0and the second-order features, at 2690 and 2910 cm-1<\/sup>.The\u00a0G band\u00a0position\u00a0(1584cm-1<\/sup>)\u00a0of\u00a0our reduced graphene oxide powder sample\u00a0is in good agreement with the literature, but the position is\u00a03 cm-1<\/sup>\u00a0higher than that of\u00a0the initial graphite (1581 cm-1<\/sup>).This shift was also observed when going from\u00a0a graphite crystal to a single graphene sheet,\u00a0in which the G band\u00a0shifts to a value\u00a03\u2013 6 cm-1\u00a0<\/sup>higher than for\u00a0bulk graphite.\u00a0The\u00a0D\u00a0band around\u00a01350 cm-1<\/sup>\u00a0arises from\u00a0disorder, and is very weakin a single graphene sheet\u00a0but increases in intensity with\u00a0the number of layers.\u00a0Thus, the shift of the\u00a0G\u00a0band and relatively intense\u00a0D\u00a0band indicate\u00a0small stacks of quite disordered graphene sheets.<\/p>\n

\u53c2\u8003\u6587\u732e\uff1a\u00a0Srinivas G., Carbon, 2010, 4 8, 630-635.<\/p>\n","protected":false},"excerpt":{"rendered":"

\u64b0\u6587\uff1a\u738b\u6d77\u71d5 \u00a0\u6240\u5c5e\u4e13\u680f\uff1aSCI\u8bba\u6587\u5199\u4f5c\u5b9e\u9a8c\u5ba4 \u524d\u8a00\uff1a \u5df2\u7ecf\u5f88\u957f\u65f6\u95f4\u6ca1\u6709\u66f4\u65b0\u201c\u7ec6\u8bf4\u8868\u5f81\u201d\u680f\u76ee\u4e86\uff0c\u4eca\u5929\u6765\u8ddf\u5927\u5bb6\u5206\u4eab\u4e00\u4e0bRaman\u7684\u5177\u4f53\u5199\u6cd5\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u6709\u6240\u5e2e\u52a9\uff01\u6309\u7167\u60ef\u4f8b\uff0c\u84dd\u8272\u5b57\u4f53\u90e8\u5206\u4e3a\u6a21\u677f\u3002 1.\u00a0\u00a0\u5982\u4f55\u975e\u5e38\u8be6\u7ec6\u5730\u63cf\u8ff0Ra … <\/p>\n

\u7ee7\u7eed\u9605\u8bfb\u201cSCI\u8bba\u6587\u4e2d\u5982\u4f55\u63cf\u8ff0Raman\u7684\u5b9e\u9a8c\u7ed3\u679c\uff1f\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":22360,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[9],"tags":[],"_links":{"self":[{"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/posts\/22359"}],"collection":[{"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/comments?post=22359"}],"version-history":[{"count":1,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/posts\/22359\/revisions"}],"predecessor-version":[{"id":22361,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/posts\/22359\/revisions\/22361"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/media\/22360"}],"wp:attachment":[{"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/media?parent=22359"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/categories?post=22359"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kuaiqikan.com\/wp-json\/wp\/v2\/tags?post=22359"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}