Beyond Surface-Localized Reaction Paradigm: Intramacropore-Confined Thermal-Field-Driven Photothermal Reactivity Leap

Abstract

Although photothermal reactions have gained extensive attention, their surface-localized nature─where heat concentrates on nanoscale surfaces─leads to suboptimal chemical reactivity. This study establishes an intrapore-confined thermal-field-driven reaction paradigm with unprecedented photothermal reactivity, through investigations of photothermal Congo Red (CR) pyrolysis in three-dimensional ordered macroporous carbon (OMC) versus nonmacroporous solid carbon (SC). Two model systems are constructed: (1) intrapore-confined configuration: fluorine–cerium nanodomains with ultrahigh CR adsorption capacity are anchored onto macroporous walls to achieve uniform CR distribution in OMC; (2) surface-localized pathway: CR is blended on the external surface of SC, decoupling intrapore confinement and surface localization mechanisms. The intrapore-confined system demonstrates transformative advantages: near-complete CR pyrolysis (>99.00 vs 39.89%), a 27.73-fold increase in rate constants (4.00 vs 0.14%/s), and a 30.71-fold enhancement in energy efficiency. Finite element analysis reveals an intrapore-confined thermal field within OMC due to its low thermal conductivity. Characterized by an inward-increasing temperature gradient, this field overcomes surface-localized limitations by reconstructing the temperature distribution, forming effective reaction driving forces. This work transcends conventional understanding of photothermal mechanisms and highlights macroporous architecture as a critical design principle for advanced photothermal materials.