Periodic Reporting for period 1 - PRISM (Probing the visible- light-driven photocatalytic mechanism to improve the photocatalytic performance of carbon nanodots (CNDs))
Période du rapport: 2024-01-01 au 2025-12-31
The PRISM project vision encompasses the Global warming and energy crisis from fossil fuels demand sustainable solar-to-fuel conversion via photocatalysis for H2 production and CO2 reduction. PRISM addresses limitations of conventional UV-absorbing carbon nanodots (CNDs) by developing visible-light-active, low-cost, metal-free photocatalysts through molecular doping.
The objectives of e- PRISM are:
(1) Synthesize structurally-defined CNDs with extended visible absorption and photostability via doping strategies;
(2) Quantify HER/CO2RR performance and elucidate proton-coupled electron transfer (PCET) mechanisms using advanced spectroscopy/electrochemistry.
Pathway to impact: Rational design principles for selective solar fuel catalysts, advancing EU Green Deal clean energy goals.
Scale: Enables efficient water splitting/CO2-to-methane, replacing expensive metals for scalable green fuels.
The objectives of e- PRISM are:
(1) Synthesize structurally-defined CNDs with extended visible absorption and photostability via doping strategies;
(2) Quantify HER/CO2RR performance and elucidate proton-coupled electron transfer (PCET) mechanisms using advanced spectroscopy/electrochemistry.
Pathway to impact: Rational design principles for selective solar fuel catalysts, advancing EU Green Deal clean energy goals.
Scale: Enables efficient water splitting/CO2-to-methane, replacing expensive metals for scalable green fuels.
The main results from the work performed during the reporting period along the different WPs is:
(WP1): Microwave-synthesized molecular-doped CNDs (DAP-CNDs, PFV-CNDs, DAPh-CNDs) from L-Arg/EDA/aromatic amines. Purified via dialysis (500Da). Characterized: 1H NMR (aromatic 7-9ppm), XPS (enhanced sp2 C/graphitic N), FT-IR (C=O/C=C), UV-Vis/PL (visible bands >400nm matching molecules), TEM/AFM. WP1A partly (doping), WP1C largely (molecules-CNDs), WP1B not (couplings).
(WP2) HER: DAP-CNDs 0.8 mmol H2/1h (pH8, AM1.5 Xe). CO2RR: PFV-CNDs 0.08 µmol CH4 (pH8). MV2+ reduction visible-active. Stability superior to free molecules. TAS/EC datasets (secondment), Pourbaix/CV started, Global analysis ongoing. Structure-selectivity: phenazine HER, acridine CO2RR.
(WP1): Microwave-synthesized molecular-doped CNDs (DAP-CNDs, PFV-CNDs, DAPh-CNDs) from L-Arg/EDA/aromatic amines. Purified via dialysis (500Da). Characterized: 1H NMR (aromatic 7-9ppm), XPS (enhanced sp2 C/graphitic N), FT-IR (C=O/C=C), UV-Vis/PL (visible bands >400nm matching molecules), TEM/AFM. WP1A partly (doping), WP1C largely (molecules-CNDs), WP1B not (couplings).
(WP2) HER: DAP-CNDs 0.8 mmol H2/1h (pH8, AM1.5 Xe). CO2RR: PFV-CNDs 0.08 µmol CH4 (pH8). MV2+ reduction visible-active. Stability superior to free molecules. TAS/EC datasets (secondment), Pourbaix/CV started, Global analysis ongoing. Structure-selectivity: phenazine HER, acridine CO2RR.
PRISM advances solar fuel technology by engineering programmable carbon nanodots that efficiently use visible sunlight to convert water into hydrogen and CO2 into methane, addressing two major climate challenges at once: clean energy production and carbon recycling. Unlike conventional photocatalysts that rely mainly on UV light and degrade quickly, PRISM embeds specific organic molecules inside protective carbon nanodots, enabling stable light absorption beyond 400 nm and sustained catalytic activity. Crucially, it demonstrates for the first time a molecular “switch” effect: phenazine-functionalized nanodots selectively produce hydrogen from water, while acridine-functionalized nanodots drive CO2 reduction to methane, allowing rational design of catalysts tailored to desired fuels. With laboratory performance reaching 0.8 mmol h⁻¹ hydrogen evolution and 0.08 µmol methane production under simulated sunlight (TRL 3 proof-of-concept), PRISM establishes clear design rules for low-cost, stable, visible-light-driven photocatalysts and lays the groundwork for scale-up, patenting, and industrial translation toward practical solar fuel generation.