Materials Chemistry and Physics 125 (2011) 838–845 Contents lists available at ScienceDirect Materials Chemistry and Physics journal homepage: www.elsevier.com/locate/matchemphys A comparative study on reactions of n-alkylamines with tungstic acids with various W–O octahedral layers: Novel evidence for the “dissolution–reorganization” mechanism Deliang Chen a,b,c,∗ , Tao Li a , Li Yin a , Xianxiang Hou a , Xiujun Yu a , Yang Zhang a , Bingbing Fan a , Hailong Wang a , Xinjian Li b , Rui Zhang a,d , Tiecui Hou a , Hongxia Lu a , Hongliang Xu a , Jing Sun c , Lian Gao c a School of Materials Science and Engineering, Zhengzhou University, 100 Science Road, Zhengzhou 450001, PR China b School of Physics and Engineering, Zhengzhou University, 100 Science Road, Zhengzhou 450001, PR China c The State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050, PR China d Laboratory of Aeronautical Composites, Zhengzhou Institute of Aeronautical Industry Management, University Centre, Zhengdong New District, Zhengzhou 450046, PR China article info Article history: Received 25 June 2010 Received in revised form 27 August 2010 Accepted 18 September 2010 Keywords: Inorganic–organic layered hybrid Tungstic acids Multilayers Crystal growth abstract The aim of this paper was to provide a convincing experimental research to demonstrate a dissolution–reorganization mechanism for the formation of tungstate-based inorganic–organic hybrid nanobelts by comparatively investigating the reaction behaviors of H 2 WO 4 and H 2 W 2 O 7 ·xH 2 O with n-alkylamines (C m H 2m+1 NH 2 , m = 4–10). The formation of tungstate-based hybrid nanobelts derived from the reactions between n-alkylamines and H 2 WO 4 with single-octahedral W–O layers was investigated with a detailed comparison with those between n-alkylamines and H 2 W 2 O 7 ·xH 2 O with double-octahedral W–O layers. H 2 WO 4 and H 2 W 2 O 7 ·xH 2 O reacted with n-alkylamines, respectively, in reverse-microemulsion-like media. The obtained products were characterized by XRD, FT-IR, TG–DTA and SEM. The results indicated that the products derived from H 2 WO 4 and those from H 2 W 2 O 7 ·xH 2 O were similar in compositions, microstructures and morphologies. The structural analysis indicated the prod- ucts were tungstate-based inorganic–organic hybrid one-dimensional belts with highly ordered lamellar structures by alternately stacking organic n-alkylammonium bilayers and inorganic single-octahedral W–O layers. The n-alkyl chains in the above hybrid nanobelts from H 2 WO 4 and H 2 W 2 O 7 ·xH 2 O took on a bilayer arrangement with tilt angles of 65 ◦ and 74 ◦ , respectively. The similarities in the microstruc- tures of the products from H 2 W 2 O 7 ·xH 2 O and H 2 WO 4 demonstrated that the double-octahedral W–O layers of H 2 W 2 O 7 ·xH 2 O were decomposed during the reactions. The changes of inorganic W–O layers and the morphologic changes of the tungstic-acid precursors before and after the reactions corroborated the dissolution–reorganization mechanism. © 2010 Elsevier B.V. All rights reserved. 1. Introduction Intercalation chemistry is one of the Chimie Douce approaches to construct inorganic–organic hybrid compounds by inserting organic guest species into a layered inorganic compound [1–5]. The resultant hybrid compounds usually integrate the advantages both of the organic guest species and of the inorganic frameworks [6,7]. There have been a great number of reports on how to construct novel materials and structures via intercalation chemistry, and the ∗ Corresponding author at: School of Materials Science and Engineering, Zhengzhou University, 100 Science Road, Zhengzhou 450001, PR China. Tel.: +86 371 63818662; fax: +86 371 63818662. E-mail addresses: dlchen@zzu.edu.cn, dlchennano@hotmail.com (D. Chen). as-obtained intercalation compounds have wide applications in catalysis, environmental purification, optics and chemical sensors [8–17]. In addition, inorganic–organic hybrids are suitable precur- sors to produce nanostructures with controllable morphologies and microstructures [18,19]. Tungsten oxide hydrates include H 2 WO 4 (or H 2 WO 4 ·H 2 O) with single-octahedral W–O layers and H 2 W 2 O 7 ·xH 2 O with double- octahedral W–O layers, both of which can be used as the host compounds for synthesis of inorganic–organic hybrid materials [16,20–23].H 2 WO 4 (or H 2 WO 4 ·H 2 O) can be easily purchased. John- son et al. [20] reported a layered inorganic–organic hybrid of WO 3 C 5 H 5 N derived by heating H 2 WO 4 with excess pyridine in the presence of molecular sieves at 423 K. H 2 W 2 O 7 ·xH 2 O can be synthesized by selectively leaching Bi 2 O 2 layers from the cation- deficient Aurivillius phase of Bi 2 W 2 O 9 [24,25]. There are many 0254-0584/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.matchemphys.2010.09.039