(Invited) Programmed Assembly of Designer Solids from Molecular Building Blocks: A Route Towards Digitalization of Materials Research?

Abstract

Realizing multifunctional “Designer Solids” by programmed assembly of building units taken form libraries is a very appealing objective in connection with Materials Research entering the Information Era. Metal-organic frameworks (MOFs) have attracted a huge interest in this context, owing to their enormous wealth of different compounds – the number of characterized elements of this rapidly growing class of materials has just exceeded 100.000. Here, we will focus on a subset of MOF-based functional materials, including electrochemical, photoelectrochemical, photovoltaic and optical devices. In addition to 3D structures, also 2D interfaces in MOF heterostructures are of interest, e.g. with regard to photon-upconversion. Since the fabrication of reliable and reproducible contacts to MOF-materials represent a major challenge, we have developed a layer-by-layer (lbl) deposition method to produce well-defined, highly oriented and monolithic MOF thin films on a number of different substrates. The resulting films are referred to as SURMOFs [1,2]. The fabrication of hetero-multilayers (see Fig. 1) is rather straightforward with this lbl method. In this talk, we will describe the principles of SURMOF fabrication as well as the results of systematic investigations of electrical and photophysical properties exhibited by empty MOFs and after loading their pores with functional guests. As a final point, we will discuss further applications realized by loading MOFs with nanoparticles or quantum dots. We will close with a more general discussion on the potential of programming functionalities into MOFs using in-silico screening methods.[3]