Liquid-phase epitaxial layer by layer brushing fabrication of metal-organic frameworks films

Development of metal-organic framework (MOF) films is of great importance to expand their applications. Herein, we report a facile and universal method of liquid-phase epitaxial (LPE) layer by layer (LBL) brushing approach for fabricating MOF films on various substrates in a high-throughput fashion. This MOF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent consumption. Moreover, this LBL brushing approach has been implemented successfully to assemble various MOF films, including HKUST-1, zeolitic imidazolate framework-8 (ZIF-8), Cu(bdc), and Cu₂(L)₂P (L = bdc, ndc, and cam; P = dabco and bipy). Afterwards, the classic MOF HKUST-1 and ZIF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds (VOCs) selective sensing and water purification applications. This study demonstrates that this LBL brushing preparation method can be employed to synthesize various MOF films with a variety of characteristics to realize their sensing and separation applications.