Solar-Powered CO₂ Capture and Release Using Amine-Functionalized Plasmonic Titanium Nitride Nanoparticles

We report the first use of titanium nitride (TiN) nanoparticles functionalized with (3-aminopropyl)-triethoxysilane (APTES) for reversible CO₂ capture and release under simulated flue gas conditions via plasmonic heating. The localized photothermal effect of TiN enables low-energy desorption of CO₂, circumventing the high thermal loads typically required for sorbent regeneration. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and mass spectrometry (MS) reveal distinct carbonaceous surface species and reaction pathways modulated by material stability, energy input, and capture medium. The TiN-APTES hybrid system demonstrated excellent durability and desorption efficiency across multiple cycles, establishing a mechanistically distinct and energetically favorable platform for CO₂ cycling. These findings highlight a new direction in photothermally driven gas separations with implications for scalable, low-carbon capture technologies.