Transforming Carbon Capture Technology: Peak-Absorption Targeted Photothermal Approach for Energy-Efficient CO₂ Desorption

MOTIVATION

Carbon capture technology faces significant challenges, particularly the high energy required to release CO₂ from sorbents using traditional heating methods. Our innovative approach employs narrowband light precisely tuned to match the absorption peak of photothermal sorbents, enabling rapid heating above 100 °C within seconds—without causing degradation. This Peak Absorption Targeted Photothermal Desorption method can reduce energy consumption by up to 90% compared to conventional techniques, allowing for faster and more sustainable CO₂ release. This breakthrough aligns with the European Green Deal’s goal of carbon neutrality by 2050, offering a promising route to cleaner, more cost-effective carbon capture solutions.

HELICOSS AIM and OBJECTIVES

To reach the project’s ambitious goal, i.e., establishing Peak Absorption Targeted PT desorption and gaining new knowledge investigating PT-process affecting factors, the following scientific objectives have been formulated:

To develop cheap, environmentally sustainable, robust and highly porous (≥ 1000 m²/g for carbonaceous-based and ≥ 800 m²/g for inorganic-based) PT-active monolithic sorbent with moderate to high sorbent capacity (> 1.5 mmol CO₂/g_sorbent at RT).
To reveal the optimal structure of the sorbent with maximal content of PT-active materials exposed to light, achieving maximised light-to-heat-conversion efficiency.
To investigate the heat propagation through PT-active monolithic sorbents.
To thoroughly characterise materials' optical properties to determine their λ_max
To exploit PT-triggered CO₂ desorption by targeting the materials λ_maxto attain peak photothermal conversion and achieving maximum regeneration efficiency (≥ 95 %) over 100 cycles.

METHODOLOGY

Work Package 1: Fabrication and characterisation of photothermally active monolithic sorbents:

Preparation of starting nanopowders: Non-toxic and low-cost sorbents, displaying high CO₂ uptake capacity will be employed. These include activated carbon (AC), porous silica (SiL), silicon carbide (SiC) and silicon nitride (SiN)
Preparation of PT-active monoliths: Low-dimensional PT-active monolithic sorbents, ≤ 2 x 2x 2 cm, will be prepared. Composite monoliths will be prepared from a sorbent-PT nanoparticles mixture using freeze casting (FC), Pickering emulsion templating (PiET), sol-gel (SG) method, by subsequent incorporation, dip-coating, co-precipitation and sputtering of PT-nanoparticles on the surface of pure sorbent monoliths

Work Package 2: Modelling of the photothermally active monolith sorbent’s structure, heat propagation and desorption kinetics:

theoretical modelling based on experimental data gained from WP1 and WP3 will be used to reveal the ideal dispersion of PT nanoparticles in the monolithic sorbent. The study will also include the effect of PT nanoparticle dispersion on heat propagation through the monolith
different models such as Langmuir, Brunauer, Emmet, and Teller (BET), and Jura and Harkins will be used to investigate desorption kinetic under PT conditions

Work Package 3: Peak Adsorption Targeted photothermally triggered CO₂ desorption: