Metal organic framework-based Janus nanomaterials: rational design, strategic fabrication and emerging applications

Janus nanoparticles (JNPs) with dual segments comprising chemically distinct compositions have garnered the attention of researchers in the past few years. The combination of different materials with diversified morphology, topology, and distinct physico-chemical characteristics into the single Janus nanocrystal has yielded multifarious capabilities for a myriad of emerging applications involving catalysis, gas separation, electro-catalysis, adsorption and energy storage. However, the traditional Janus entities significantly lack the need for populous active sites and high surface area. To overcome the textural hurdles and improve the functionalities of JNPs, porous MOFs were eventually introduced into Janus particles. MOFs are well endowed with varied pore apertures, structures, large surface areas and tailored characteristics, making them potentially invaluable for Janus fabrication. Depending upon the usage, MOFs can be explored to design Metal@MOF, polymetalic@MOF, MOF@MOF and MOF-derived JNPs. In this regard, we have represented a holistic summarization of the design, synthesis and emerging applications of a rising class of multi-functionalized MOF-based Janus nanomaterials. Moreover, this article will significantly aid researchers with a vision of creating dual-composition porous nanomaterials as the MOF-based Janus nanoparticles is at infancy. Janus MOFs holds a novel strategy in overcoming the shortcomings of conventional metal-organic frameworks (MOFs) as well as non-porous Janus nanoparticles by exhibiting non-centrosymmetry and multi-functionality.