Concept and Methodology
METAMORPH will deliver an integrated approach for CO2 capture and conversion to methanol and other valuable chemicals using hybrid nanostructured membranes. The key innovation of METAMORPH is the combination of CO2 adsorbers and photocatalytic nanoparticles in one system, designed to reduce the CO2 diffusion-to-catalyst path. This is expected to have a synergistic effect (provide CO2 to catalysts and consume adsorbed CO2 allowing further adsorption and catalysis) and lead to a significant increase in the photoconversion efficiency. Moreover, the hybrid particles will, in addition, be combined with the nanofibrous membranes further increasing the surface area and providing the mechanical stability that will be integrated into optimized photoreactors for carbon-neutral synthesis of valuable organic molecules. METAMORPH is based on the integration of the following components:
- CCS material based on carbonized PANi with CO2 sorption capacity.
- Novel, safe and cheap photocatalysts based on quantum dots combined with inorganic NPs (i.e. TiO2).
- Hybrid carbonized PANi/photocatalytic particles with combined CO2 sorption and photocatalytic efficacy.
- Novel nanostructured and bendable electrospun membranes.
- Special photoreactors designed to increase the efficacy of light-harvesting.
The project goals will be achieved by completing the following tasks (see Figure 1):
Figure 1: Summary of the METAMORPH’s work packages and timeline.
WP1 – Photocatalytic nanoparticles (SINTEF)
One of the major challenges in the development of cost-effective and efficient solar fuel generation is the scarcity of highly active, cheap, and abundant photocatalysts. The project will focus on synthesis strategies of modified TiO2 (cheap, abundant, stable) nanoparticles and utilization of co-catalysts based on earth abundant elements (ex. Co, Cu or Ni-based) as well as carbon based nanomaterials (graphene quantum dots, C3N4).
WP2 – Hybrid polyaniline nanoparticles (UCT, SINTEF)
To increase the efficiency of the CO2 conversion the project aims to incorporate photocatalyst nanoparticles into hybrid materials, i.e. conductive polymers and carbon-based materials. In the case of conductive polymers, we will use our methodology to prepare composite porous materials  and photocatalytic nanoparticles will be coated by the layer of conductive polymer made out of polyaniline, polypyrrole or polythiophene [1, 4]. This procedure will be initially optimized for TiO2 particles , but when available other photocatalytic particles developed in WP1 will be considered as well.
WP3 – Preparation of nanofiber membranes with CO2 capture/photocatalytic nanoparticles for carbon capture and utilization (CCU) (INCU, UJEP, SINTEF)
The nanoparticles developed in WP1 and WP2 will be embedded into nanofibers using a high-throughput electrospinning system (see Figure 2). The project will primarily focus on polyacrylonitrile, polyvinyl difluoride, polyethylene terephthalate, polyurethanes, polyvinyl alcohol (crosslinked)-based non-degradable fibres.
Figure 2: Multiple layers of nanostructures of METAMORPH membranes: the nanosized electrospun fibres will be loaded with adsorptive/catalytic nanoparticles. The nanoparticles will be composed of the porous carbonized PANi loaded with novel photocatalyst made of a combination of materials.
WP4 – Polymer nanofibers modified with carbonized PANi and zeolite nanoparticles for selective CO2 capture and storage (CCS) (UCT, UJEP, INCU)
The carbonized PANi nanoparticles developed at UCT will be loaded into nanofibers (INCU) either by blend needleless electrospinning, sonocoating (modified dip coating) or spray coating.
WP5 – Systems for carbon capture and utilization CCU (SINTEF, UCT)
The design of the photoreactor will be dependent on the form of the prepared photocatalytic materials. The photoreactors will be developed in two settings:
- Single-step CO2 capture/photocatalytic conversion will be based on CO2 enrichment via a permeable foil designed for the terrestrial application.
- Two-step system with separated CO2 capture and photocatalytic conversion where CO2 sorption and CO2 photoconversion will be split in two separate processes.
WP6 – Up-scaling: METAMORPH membrane production (INCU, SINTEF)
Based on functional studies, the production of the hybrid CO2 absorption and photocatalytic membranes will be up-scaled. A new pilot production line will be constructed and tested at InoCure.
WP7 – Up-scaling: photoreactor development (UCT, SINTEF) – M12-M40
The produced membranes will be integrated into newly designed photoreactors developed at SINTEF and UCT.
WP8: Functional studies in a real environment – terrestrial application (SINTEF)
The aim of this work package is to compare the proposed system with the conventional technologies with respect to environmental and economic criteria, using Life Cycle Assessment (LCA) and Life Cycle Cost analysis (LCCA), respectively.