A Novel Cu_xO Nanoparticles@ZIF-8 Composite Derived from Core–Shell Metal–Organic Frameworks for Highly Selective Electrochemical Sensing of Hydrogen Peroxide

Abstract

A novel core-shell heterostructure of CuxO nanoparticles@zeolitic imidazolate framework (CuxO NPs@ZIF-8) was successfully prepared through facile pyrolysis of a nanocrystalline copper-based metal-organic framework [nHKUST-1, i.e., Cu3(BTC)2 (BTC = 1,3,5-benzene-tricarboxylate)]@ZIF-8, based on the different thermal stability of the two metal-organic frameworks (MOFs). The small CuxO NPs derived from nHKUST-1 were uniformly dispersed inside the host material and provided active sites, while ZIF-8 kept the original structure as the molecular sieving shell. Owing to the proper pore shape and pore size of ZIF-8, H2O2 could diffuse through the shell, but bigger molecules could not pass. Thus, the composite material exhibited high selectivity when it was used to construct a H2O2 sensor. In addition, the sensor showed an extended linear detection range (from 1.5 to 21442 μM), low detection limit (0.15 μM), and high sensitivity, due to the good electrocatalysis of CuxO NPs and the synergistic effect of the core-shell structure.

Strategies for Improving the Functionality of Zeolitic Imidazolate Frameworks: Tailoring Nanoarchitectures for Functional Applications

“…or bimetallic alloys composed of two different metal NPs such as AuAg, PtPd, AgPd, etc. These metal NPs@ZIF composites have been employed in catalysis for various organic reactions such as hydrogenation, dehydrogenation, hydroformylation, oxidative degradation, oxidation as well as in electrochemical sensing, gas storage and so on.…”

Metal–Organic Frameworks and Their Composites: Synthesis and Electrochemical Applications

“…Among these composites, MOFs used as electrochemically active materials are still staying in the primary stage on account of their limited conductivity, large steric hindrance, and unmatched electrolyte. Here, we relate to metal including Fe, Co, Zn, Ag, Au, Pt, and Si; metal oxide including ZnO, Fe 3 O 4 , SnO 2 , MnO 2 , and CuO; metal salts including MoS x , Ni 2 (CO 3 )(OH) 2 , and the host MOF frameworks including MIL‐53(Fe), ZIF‐8, MIL‐100(Cr), UiO‐66, as well as a few new MOF structures . As ordered porous materials, MOFs are fit for the uniform distribution of guests, which is very important, especially for nanometal catalysts.…”

“…Meanwhile, this composite shows a good cycling stability over 500 cycles. A novel Cu x O nanoparticle@zeolitic imidazolate framework (Cu x O NP@ZIF‐8) was also fabricated with ZIF‐8 as host ( Figure ) . Their synthesis is interesting that this composite Cu x O NP@ZIF‐8 is from the facile pyrolysis of HKUST‐1@ZIF‐8 nanocrystal based on the different thermal stability of the two MOFs, where HKUST‐1 is converted into Cu x O NPs, uniformly dispersing inside the host materials of ZIF‐8, because ZIF‐8 can remain its original structure under the same pyrolysis temperature.…”

“…Schematic diagram of the construction of Cu x O NP@ZIF‐8. Reproduced with permission . Copyright 2016, American Chemical Society.…”

“…The functional surface area and high porosities of MOFs play crucial role in many functional properties including proton conduction, supercapacitors, and Li‐based batteries. Furthermore, the development of MOF composites by introducing new electrochemical materials into pristine MOFs enhances the MOF conductivity and boosts the electrochemical applications of MOFs. The implantation of functional materials into the MOF pores further broadens the applications of MOFs and improves the cycling performance.…”