Application of Metal-Organic Frameworks and Covalent Organic Frameworks as (Photo)Active Material in Hybrid Photovoltaic Technologies

Abstract

Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are two innovative classes of porous coordination polymers. MOFs are three-dimensional materials made up of secondary building blocks comprised of metal ions/clusters and organic ligands whereas COFs are 2D or 3D highly porous organic solids made up by light elements (i.e., H, B, C, N, O). Both MOFs and COFs, being highly conjugated scaffolds, are very promising as photoactive materials for applications in photocatalysis and artificial photosynthesis because of their tunable electronic properties, high surface area, remarkable light and thermal stability, easy and relative low-cost synthesis, and structural versatility. These properties make them perfectly suitable for photovoltaic application: throughout this review, we summarize recent advances in the employment of both MOFs and COFs in emerging photovoltaics, namely dye-sensitized solar cells (DSSCs) organic photovoltaic (OPV) and perovskite solar cells (PSCs). MOFs are successfully implemented in DSSCs as photoanodic material or solid-state sensitizers and in PSCs mainly as hole or electron transporting materials. An innovative paradigm, in which the porous conductive polymer acts as standing-alone sensitized photoanode, is exploited too. Conversely, COFs are mostly implemented as photoactive material or as hole transporting material in PSCs.

Process of metal–organic framework (MOF)/covalent–organic framework (COF) hybrids-based derivatives and their applications on energy transfer and storage

“…1,2 In this regard, MOFs and COFs have been vastly employed in diverse fields, such as gas separation/adsorption, cancer therapy, biosensing, catalysts, and batteries. 3–5 Although extensive efforts have been devoted to the investigation of diverse sole MOFs and COFs, they still cannot directly realize some specific needs. For instance, most monometallic MOFs often show inferior electrochemical activity, meaning that they rarely serve as electrocatalysts for energy transfer and electrode materials for energy storage.…”

Structural Characteristics and Environmental Applications of Covalent Organic Frameworks

“…In recent years, adsorption-(entrapment) and membrane (size exclusion)based purification have attracted immense research and industrial interest due to their low energy consumption as well as simple and environmentally friendly operation. Various amorphous materials such as hyper-cross-linked polymers (HCPs) [1,2], porous organic polymers (POPs) [3,4], conjugated microporous polymers (CMPs) [5][6][7], and activated carbon [8][9][10]; and crystalline materials such as metal-organic frameworks (MOFs) [11][12][13][14] and zeolites [15][16][17][18][19], have shown excellent preliminary separation performance. Covalent organic frameworks (MOFs) [11][12][13][14] and zeolites [15][16][17][18][19], have shown excellent preliminary separation performance.…”

“…Various amorphous materials such as hyper-cross-linked polymers (HCPs) [1,2], porous organic polymers (POPs) [3,4], conjugated microporous polymers (CMPs) [5][6][7], and activated carbon [8][9][10]; and crystalline materials such as metal-organic frameworks (MOFs) [11][12][13][14] and zeolites [15][16][17][18][19], have shown excellent preliminary separation performance. Covalent organic frameworks (MOFs) [11][12][13][14] and zeolites [15][16][17][18][19], have shown excellent preliminary separation performance. Covalent organic frameworks (COFs) are a class of crystalline framework material synthesized from purely organic building blocks.…”

“…Some of the important applications and various types of COFs are shown in Scheme 1 and Figure 1, respectively. Among many important aspects, COFs offer pore post-functionalization due to their organic nature, for specific desirable applications such as gas storage [23][24][25], catalysis [26,27], electronic devices [11,28], electrode material for batteries [29][30][31][32], etc. The most attractive feature of COFs is their framework structure with uniform and extended porous channels, attracting the interest of scientists in the purification/separation field.…”

A Theoretical Evaluation of the Efficiencies of Metal-Free 1,3,4-Oxadiazole Dye-Sensitized Solar Cells: Insights From Electron-Hole Separation Distance Analysis.

“…Research has recently focused on metal-organic frameworks (MOFs) as dye molecules due to their robustness, porosity, light-harvesting properties, thermal stability, and structural versatility. However, their insulating properties limit their usage [8][9][10][11][12][13][14]. In the past, Rubased complexes held the top place for the highest efficiency in DSSCs of over 11% but were overtaken first in 2014 by zinc porphyrin compounds with an efficiency of 13%, and soon afterwards in 2015, by two co-sensitized metal-free organic dyes with an efficiency of 14.30% [15].…”