Establishment of heterodinuclear replacement complexation and its application to direct determination of iron in natural water with dibromo-o-nitrophenylfluorone

The chromophore dibromo-o-nitrophenylfluorone (DBNPF) was used to complex Fe(III) and Cu(II) at pH 5.88. Fe(III) can competitively replace Cu(II) from its dinuclear complex Cu(DBNPF)Cu, and forms the Cu(DBNPF)Fe heterodinuclear complex. The Fe-DBNPF and Cu-DBNPF complexes were also characterized by the spectral correction technique. The heterodinuclear replacement complexation (HRC) is proposed and first used for the quantitative detection of iron in trace level with high sensitivity and good selectivity by the light-absorption ratio variation approach. The limit of detection of Fe is 1.0 μg L⁻¹. The method has been successfully applied to the direct determination of Fe(II, III) dissolved and bound to suspended substances in natural water.     

金属元素替换对锌-铜基金属有机骨架材料的光吸收与能带特性的影响

选择常规的锌、铜作为金属离子、对苯二甲酸（BDC）作为有机配体，通过溶剂热法和元素替换法合成出Zn-Cu基MOFs材料。通过XRD、UV-Vis DRS、SEM、FT-IR、UPS和XPS等手段表征和研究，发现Zn（BDC）的光吸收位于紫外光波段（<400 nm），而Cu（BDC）光吸收拓宽至整个可见光波段（500~1 000 nm）。Zn-Cu金属离子均匀分散的产物Zn-Cu-BDC比其它产物具有更宽的光吸收范围、强度和更窄的带隙；不同的合成途径导致Zn-Cu基MOFs材料表现出性质差异。