About this Research Topic
Development of renewable energy technologies with the aim to harness and utilize abundant resources and to lower the reliance of energy and chemical industries on fossil fuels is one of the major contemporary scientific challenges. This includes electricity or solar-driven conversion of water, CO2, N2, biomass and synthetic polymer wastes into fuels and value-added chemicals. Designing new catalytic and light-harvesting materials to drive these energy-demanding reactions lies at the nexus of renewable energy research. While molecular systems are appealing due to their synthetic tunability, scope for iterative improvement and suitability for spectroscopic and mechanistic studies; the robustness and recyclability of heterogeneous materials make them attractive for application in practical devices. Modular porous nanostructures and materials, in which molecular linkers are used as building blocks, represent a versatile platform that combines the benefits of molecular systems and solid-state materials for application in the field of catalysis related to renewable energy.
Heterogenization of molecular species, including catalysts and photosensitizing dyes, within nanostructured materials is an effective strategy to improve atom-efficiency of the catalysis, stabilize the molecules during turnovers and allow recycling of the materials. Porous materials, such as metal-organic frameworks (MOFs), covalent organic frameworks (COFs), covalent triazine frameworks (CTFs), porous organic polymers (POPs), zeolites and mesoporous metal-oxides, provide ideal scaffolds for accommodating molecular catalysts and dyes due to their large internal surface area that allows high loading of molecular species while enabling accessibility to reactants. In addition to direct immobilization of the molecular species on porous support via covalent or non-covalent means, catalysts and photosensitizers can also be used as molecular linkers to construct MOFs and COFs. Notably, the latter approach offers precise control over spatial orientation of the active units, which is advantageous for tuning charge-transfer and/or energy transfer during electrocatalytic or photocatalytic applications. Metal-organic coordination cages (MOCs) can be considered as miniature version of MOFs, which contain similar building blocks but only few discrete pores and thus, higher solubility. While these porous materials represent a promising class of materials with large untapped potential towards application in artificial photosynthesis, their successful implementation in practical devices require better understanding of several factors including their charge-transfer properties, effect of pore engineering on catalysis, semiconducting behavior and diffusion of substrates/products through the pores.
The Research Topic welcomes contributions focused on the utilization of porous materials or discrete molecular cages for electrochemical or photochemical applications toward fuel and chemical synthesis. Potential topics include, but are not limited to:
• Design and synthesis of novel porous materials and discrete cages
• Design of novel semiconducting POPs towards their photocatalytic applications
• Design of novel conductive porous materials and related electrochemical studies
• Proof-of-concept functional studies on the performance in proton reduction, carbon-based fuel production, water oxidation, chemical energy conversion
• Catalyst incorporation either as building block or guest
• Experimental and theoretical studies on mechanistic aspects of novel porous materials and discrete cages
• Host-guest energy- and electron transfer studies
Keywords: Renewable energy, Porous polymers, Metal-organic frameworks, Covalent organic frameworks, design and synthesis
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.