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A facile strategy for the synthesis of acidic ionic liquid based UiO-67 type MOFs was developed in this study.Brønsted acids (H 2 SO 4 , CF 3 SO 3 H and hifpOSO 3 H (hexafluoroisopropyl sulfuric acid)) were introduced into UiO-67-bpy (bpy ¼ 2,2 0 -bipyridine-5,5 0 -dicarboxylic acid) frameworks by reacting with bipyridyl nitrogen to introduce the properties of an acidic ionic liquid into the frameworks. The prepared catalysts, denoted as UiO-67-HSO 4 , UiO-67-CF 3 SO 3 and UiO-67-hifpOSO 3 , were characterized by XRD, SEM, FT-IR, EA, TGA and N 2 adsorption-desorption studies. The relatively high surface area was still maintained and acidic active groups were uniformly dispersed in the frameworks. The catalytic performance of UiO-67-HSO 4 , UiO-67-CF 3 SO 3 and UiO-67-hifpOSO 3 was evaluated by the esterification of acetic acid with isooctyl alcohol. The prepared catalysts showed good catalytic activities in the esterification, of which UiO-67-CF 3 SO 3 gave the maximum isooctyl alcohol conversion of 98.6% under optimized conditions. The catalyst could be reused five times without a significant decrease in the conversion of isooctyl alcohol, and almost no active species were leached, indicating the excellent stability and reusability of the catalyst. Our study provides one effective way to synthesize heterogeneous acidic ionic liquid catalysts consisting of isolated, well defined acidic groups that will probably attract interest in acid catalyst chemistry.

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A series of orientation-adjustable metal–organic framework (MOF) nanorods, CoFe­(dobpdc)-I to CoFe­(dobpdc)-III (dobpdc = 4,4′-dihydroxybiphenyl-3,3′-dicarboxylate), is developed on a 3D nickel foam (NF) template. By modulating the solvent composition for synthesis, the feature of MOF nanorods on the template can be varied from disorganized to a unidirectional orientation perpendicular to the NF. Well-aligned, vertically oriented CoFe­(dobpdc)-III nanorods are hydrophilic and have more exposed active sites and interfacial charge transfer ability. Consequently, they exhibit a superior activity for oxygen evolution reaction (OER) with ultralow overpotentials of 176 and 240 mV at 10 and 300 mA cm–2 in 1.0 M KOH (aq), respectively. CoFe­(dobpdc)-III also shows a record low overpotential of 204 mV at J 10 mA cm–2 among the electrocatalysts based on CoFe MOF and an excellent overpotential at a high current density (100 mA cm–2) of 312 mV in 0.1 M KOH (aq). This is the first report of a convenient method to straighten up MOF nanorods on a template for highly efficient OER.