Direct co-processing of CO2 and water to sustainable multicarbon energy products in novel photocatalytic reactor ​

Project Information

DESIRED

Grant agreement ID: 101083355

DOI

10.3030/101083355

EC signature date 14 October 2022

Start date 1 November 2022

End date 31 October 2026

Funded under

• Climate, Energy and Mobility

Total cost

€ 3 058 752,50

EU contribution

€ 3 058 752,50

Coordinated by

CONSORZIO INTERUNIVERSITARIO NAZIONALE PER LA REATTIVITA CHIMICA E LA CATALISI - CIRCC
Italy

Periodic Reporting for period 2 - DESIRED (Direct co-processing of CO2 and water to sustainable multicarbon energy products in novel photocatalytic reactor ​)

Reporting period: 2024-05-01 to 2025-10-31

Summary of the context and overall objectives of the project

At present, significant improvement in the photocatalysts and reactor technology is required for solar fuels’ production to become technically feasible, scalable, affordable, secure, sustainable, and efficient. DESIRED is a high-risk high-return project, focused on establishing the technological feasibility and sustainability of a novel fuel production system – the DESIRED system – for direct coprocessing of, possibly atmospheric, CO2 and water to produce multi-carbon (C2+) energy-rich products using sunlight as primary energy source. The DESIRED system will produce C2+ solar fuels (without overlooking C1 species such as methanol or methane) by direct coprocessing of CO2 and water using novel and recyclable hybrid photo-electrocatalysts, supported on frustules or zeolites, in an innovative photoreactor design applying, for the first time, oscillatory flow principles, combined with direct light irradiation. With regards to applications, DESIRED will focus on products, which would be used per se or as intermediates to produce drop-in fuels for sectors where direct shift to batteries or H2 is not a technically and cost-efficient option (e.g. aviation). Knowledge of the economic affordability, environmental benefits, and social acceptability of this approach will be investigated. DESIRED promotes an interdisciplinary approach to research and innovation undertaken by a consortium of 7 EU Partners and complemented by cross-cutting activities including modelling, process simulation, sustainability, and techno-economic assessment as well as impactful dissemination, communication, capacity-building and exploitation activities that support the exchange of knowledge across and beyond the consortium and project.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the second reporting period, the DESIRED project made substantial scientific, technical, and organisational progress, consolidating its position as a European frontrunner in solar-fuel technologies. The consortium advanced all major project objectives, delivered high-quality scientific outputs, and significantly strengthened the technological foundations required to demonstrate the DESIRED fuel production system at TRL 4.
Major achievements during RP2 include:
- Breakthroughs in Photocatalyst and Electrode Development
The project delivered multiple generations of novel Cu-oxide–based photocathodes with markedly enhanced stability, charge-transfer efficiency, and selectivity. Notably, DESIRED achieved:
• Multilayer Cu2O/Al2O₃/TiO2 architectures with 2.8-fold higher photocurrent and up to 69% methanol Faradaic efficiency in saline electrolytes, demonstrating compatibility with seawater conditions.
• The first demonstration of time-evolving multicarbon (C2–C₄) products from a Cu2O/Zn₅(OH)₈Cl2 heterostructure, supported by mechanistic DFT analysis connecting chloride chemistry to C–C coupling.
• A new family of hybrid inorganic–organic overlayers that suppresses photocorrosion and doubles the IPCE, extending operation to >20 h.
• New-concept materials that showcase unprecedented C–C coupling behaviour and establish new design rules for next-generation photocathodes.
These advances directly address Objective 1 and significantly expand the scientific basis for selective, stable, and energy-efficient CO2 photoreduction.

- Discovery of Bio-Sourced Frustules as Cu2O Facet Inducers
A particularly impactful discovery was the unexpected facet-selective behaviour of diatom-derived frustules, which act not merely as supports but as inorganic facet inducers for Cu2O nanostructures.
This work:
• Clarified the distinct role of mono-layer (PN) and bi-layer (Cw, Nsp) frustule morphologies.
• Demonstrated selective induction of {111} and {110} Cu2O facets, each associated with different CO2RR product pathways.
• Provided mechanistic insight, supported by DFT, linking Cu–Cu spacing to C–C coupling energetics.
These findings open a new research direction in catalyst design and provide DESIRED with a bio-inspired lever for tuning selectivity, reinforcing Europe’s innovation leadership.

- Design, Engineering and Realisation of the Level 2 Integrated Photoreactor
DESIRED completed the full engineering, construction and integration of the Level 2 photoreactor—a milestone system capable of oscillatory flow, dual-compartment PEC operation, and coupling to a customised solar concentrator.
Key achievements include:
• A validated radiation digital twin, enabling optimum reactor–collector co-design.
• A novel hybrid specular–diffuse reflector with >15% improved optical efficiency compared to purely specular CPC-type designs.
• A fully realised two-compartment, 450 mL Level 2 reactor, compatible with multiple electrode configurations and ready for TRL-4 validation in WP4.
This achievement directly advances Objectives 2 and 3 and lays the foundation for demonstrating DESIRED’s integrated fuel production concept under real solar conditions.

- Advances in Sustainability Assessment and Societal Dimensions
Work in WP5 progressed the Integrated Life Cycle Sustainability Assessment (ILCSA) methodology.
These contributions support Objective 4 and ensure that DESIRED technologies evolve within a sustainability-driven and socially acceptable framework.

- Impact, Dissemination and European Leadership
The consortium significantly intensified its dissemination and engagement activitiesholders and industry.
These achievements strengthen Objective 5 and demonstrate DESIRED’s growing influence within the global artificial photosynthesis and CCU communities.

- Overall Contribution to Long-Term Impact
Across RP2, DESIRED delivered strong evidence of technological feasibility, novel scientific concepts, robust sustainability grounding, and increasing visibility—demonstrating clear progress toward the long-term goal of enabling renewable, carbon-neutral solar fuels and contributing to the EU’s transition to a net-zero greenhouse-gases economy by 2050.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

During the second reporting period, the DESIRED consortium delivered strong scientific and technical progress, significantly advancing the development of selective and stable Cu-oxide–based photo(electro)catalysts and establishing reproducible, contamination-controlled experimental protocols across all laboratories. These achievements provide a solid basis for identifying the most promising materials for integration and scale-up.
Also, the engineering effort successfully culminated in the design, construction and assembly of the Level 2 PR and its integrated solar collector. This marks a major step toward TRL-4 readiness, enabling the project to transition from component-level optimisation to system-level validation.
Progress in sustainability assessment ensures that DESIRED technologies evolve within a robust environmental and societal context.
The consortium understands the project may well result in the development of a novel commercial product with a high market potential and has started preparing for the proper exploitation of the IP stemming from the project.
In terms of impact, the project activities are framed as having wide-ranging environmental and societal implications for human health and wellbeing and on the sustainable exploitation of energy resources, in addition to enhancing the competitiveness of the EU industry in a global context.