title: Compact film fabrication of porous coordination polymer Co3[Co(CN)6]2 and its reversible vapochromic behavior.
abstract: Films of Prussian blue analogue (PBA) Co3[Co(CN)6]2 were fabricated on porous α-alumina, ITO glass, silicon wafer and non-woven fabric substrates via a facile self-assembly method, and were characterized using infrared spectroscopy, X-ray powder diffraction and scanning electron microscope techniques. The films composed of truncated cube-shaped PBA particles are highly oriented with a preferred (100) plane on the glossy and smooth surfaces of ITO glass and silicon wafer, but crystallographically isotropic on the rough surface of porous α-alumina and non-woven fabric substrates. Compact films were achieved on porous α-alumina and surface-functionalized ITO glass. Reversible solvatochromism/vapochromism was discovered and investigated for the powdered and thin-film PBA samples. Such peculiar solvatochromism/vapochromism is related to the process of the adsorbed solvent molecules replacing the coordinated water molecules in octahedral Co(2+)-(N)4(H2O)2. The change of the Co(2+) ion's coordination atmosphere leads to the variation of crystal field strength, as a result, the d-d transitions within the Co(2+) ions are altered to give rise to a color change.
authors.affiliation: State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China. xmren@njtech.edu.cn wqjin@njtech.edu.cn and College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
authors.forename: Hua-Yu
authors.initials: HY
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China. xmren@njtech.edu.cn wqjin@njtech.edu.cn.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China. xmren@njtech.edu.cn wqjin@njtech.edu.cn and College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
authors.forename: Cui-Ping
authors.initials: CP
authors.lastname: Li
authors.affiliation: State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China. xmren@njtech.edu.cn wqjin@njtech.edu.cn and College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China. xmren@njtech.edu.cn wqjin@njtech.edu.cn and College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
authors.forename: Chen
authors.initials: C
authors.lastname: Xue
authors.affiliation: State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China. xmren@njtech.edu.cn wqjin@njtech.edu.cn.
authors.forename: Wanqin
authors.initials: W
authors.lastname: Jin