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A zeolitic imidazolate framework-8 (ZIF-8)/reduced graphene oxide (rGO) nanocomposite was formed by using an efficient synthetic method. The morphology and structure of the ZIF-8/rGO nanocomposite were characterized by scanning electron spectroscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) mapping. The ZIF-8/rGO nanocomposites were immobilized on a carbon paste electrode (CPE) to construct a high-performance nonenzymatic electrochemical H 2 O 2 sensor. A cyclic voltammetry (CV) study showed that the ZIF-8/rGO nanocomposites displayed better electrocatalytic activity toward H 2 O 2 reduction compared to that of ZIF-8. An amperometric study indicated that the H 2 O 2 sensor displayed high performance, which offered a low detection limit (0.05 μM) (S/N = 3), a high sensitivity (4.01 μA mM -1 cm -2 ), and a wide linear range (from 1.0 to 625 μM). An electrochemical reaction mechanism was proposed for H 2 O 2 reduction on the ZIF-8/rGO/CPE. Importantly, the as-fabricated H 2 O 2 sensor exhibited good reproducibility and excellent selectivity. Furthermore, the constructed high-performance sensor was utilized to monitor the H 2 O 2 levels in real samples, and satisfactory results were obtained. These results demonstrated that the ZIF-8/rGO nanocomposite can be used as a good electrochemical sensor material in practical applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The lower critical solution temperature (LCST) phase separation behaviors of thermosensitive poly( N -isopropylacrylamide) (PNIPAM) aqueous solutions were investigated by power-compensation differential scanning calorimetry (DSC). The entropic effect and hence the change of swelling state of PNIPAM polymer coils in homogeneous concentrated aqueous solutions with varied solution composition was elucidated by the isothermal enthalpy demixing recovery behaviors in distinct concentration regions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)