写文章引言部分是我的最强项。引言部分每段话都有功能和目的的,有起承转合。段落里面的几句话都是有层次的。如果能用精炼的语言把本文的背景、目的、结果、重要性有逻辑性地讲清楚,层次分明、逻辑严密、凸现写作者的某种个性,那么审稿人看了就觉得很舒服。现在我介绍最近一篇第一作者文章的引言部分。文章为:Z. Ma, H.F. Yin, S.H. Overbury, S. Dai*, Metal Phosphates as a New Class of Supports for Gold Nanocatalysts, Catalysis Letters 126 (2008) 20-30. http://dx.doi.org/10.1007/s10562-008-9627-x 关于该文的故事已经发表于《酸甜苦辣――文章背后的故事》http://zhenmafudan.ycool.com/post.2946437.html
Supported gold catalysts have many applications in ablating air pollutants, cleaning up H2 streams, and synthesizing fine chemicals [1-5]. Most gold catalysts are prepared by loading gold on oxide supports via deposition-precipitation and other methods. In addition to the size of gold nanoparticles, supports also play a key role in determining activity. It has been suggested that gold on reducible supports (e.g., TiO2, CeO2, Fe2O3) exhibits higher activity in CO oxidation than gold on non-reducible supports (e.g., Al2O3, SiO2) because the former can activate oxygen [6-8]. Nevertheless, properly prepared Au/Al2O3 [9-11] and Au/SiO2 [12-19] can also show high activities in CO oxidation.
Although certain metal salts (e.g., sulfates, phosphates) are typical solid acid catalysts [20, 21], they have rarely been used to support gold nanoparticles. Lian et al. found that Au/BaCO3 is active for CO oxidation at room temperature, but it deactivates quickly on stream [22]. Venugopal et al. and Phonthammachai et al. reported that Au/Ca10(PO4)6(OH)2 catalysts show activity in water-gas shift and CO oxidation above 100 and 50 oC, respectively [23, 24]. Au/Ca10(PO4)6(OH)2 catalyst is also useful for the wet oxidation of organic compounds in aqueous media [25]. Our group recently communicated that gold nanoparticles supported on nanosized LaPO4 (6-8 nm) are active for CO oxidation below room temperature [26]. More recently, Li and coworkers developed Au/LaVO4 nanocomposite active for CO oxidation below 50 oC [27]. However, the knowledge on the use of metal salts as supports for gold nanoparticles is still quite limited.
The previous work on Au/nano-LaPO4 [26] prompted us to raise further questions. Considering that there are numerous metal phosphates, is it possible to use metal phosphates other than LaPO4 to load gold nanoparticles? Are these metal phosphate-based catalysts active in CO oxidation, or is Au/nano-LaPO4 [26] a unique case? Are these phosphate-based gold catalysts stable on stream? In addition, considering that the homemade supports prepared using various methods under complicated conditions would lead to different particle sizes, crystal phases, morphologies, levels of residual ions from the synthesis mixture, and thus different catalytic performance, it is desirable to use commercially available supports for initial screening, while leaving the further optimization of catalysts the subject of further research.
Herein, a number of commercial metal phosphates were used as supports for loading gold via a deposition-precipitation method. The catalytic performance in CO oxidation was studied following catalyst pretreatment in O2-He at 200 or 500 oC, and relevant characterization employing ICP-OES, BET, XRD, TEM, SEM, and H2-TPR was carried out. Interestingly, gold nanoparticles can be well dispersed on many of these metal phosphate supports and show significant activities at room temperature. Since many metal phosphates are useful in acid catalysis and selective oxidation [20, 28-32], Au/metal phosphates developed here may be useful for many other reactions to be explored in the future. In addition, gold on chemically distinct supports may provide new opportunities for fundamental studies to elucidate the nature of active sites and reaction mechanisms.
最后一段话也是非常标准的写法,里面传达三个层次的意思。第一层次:本文用什么手段做了什么。这里用的是描述性的语言,而不涉及具体的、分散读者注意力的细节。第二层次:概述得到什么重要的、有趣的结果。同样也用描述性的语言。第三层意思:点明工作的意义,指出所谓applications and implications。这样的话,读者就会感到意犹未尽。我要说这些都是非常标准的写作方法,都是有理论指导的。有一本书Write Like A Chemist详细介绍了写文章每一部份的基本结构和套路,就象做广告的、说相声的人都有套路的一样。
这样的现象有的金催化文章中也见过:
M. Date et al., Angew Chem Int Ed 43 (2004) 2129.
C.Y. Mou et al., J. Catal. 237 (2006) 197.
H.G. Zhu et al., Appl. Catal. A 326 (2007) 89.
中科大黄教授在他最近文章里有详细讨论:http://dx.doi.org/10.1016/j.jcat.2008.02.012
Z. Ma, F. Zaera*, Competitive Chemisorption between Pairs of Cinchona Alkaloids and Related Compounds from Solution onto Platinum Surfaces, Journal of the American Chemical Society 128 (2006) 16414-16415. http://dx.doi.org/10.1021/ja0659323
Facile Synthesis of Ordered Mesoporous Carbons with High Thermal Stability by Self-Assembly of Resorcinol−Formaldehyde and Block Copolymers under Highly Acidic Conditions