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Metal nanoparticle (NP) catalysts promote a broad set of industrially relevant chemical reactions. To date, however, catalyst deactivation shortens their operational lifetime and undermines their economic rentability. Specifically, NP catalysts often promote undesired side reactions aside from ‘on-purpose’ hydrocarbon transformations, producing carbon-rich ‘coke’ wastes which poison the reactive NP surface on the short term. This necessitates intermittent O2 coke burn-off in between reaction periods to regenerate the NP surface, producing environmentally-harmful CO2. In addition, such reaction-regeneration cycling triggers NP sintering, causing long-term irreversible deactivation, and eventually leading to the catalyst death. During our previous beamtime at NCD-SWEET, we interrogated the influence of the redox gas cycling (e.g. repetitive O2-H2, O2-C3H8, O2-C3H8+H2) on NP sintering during propane dehydrogenation (PDH, C3H8 = C3H6 + H2) via operando GISAXS. While very successful in our attempt for PDH (see experimental report), herein, we aim to extend our developed and working gas cycling-GISAXS approach to a broader variety of reaction classes. The performance of the CO2 methanation reaction (CO2 + 3 H2 = CH4 + H2O) is known to depend on the NP structure, thus belonging to the class of ‘structure sensitive’ reactions, whereas PDH is considered as a structure insensitive reaction. NPs undergoing structure insensitive reactions have recently been shown to restructure more intensely during reaction than NPs during structure sensitive reactions. We aim to elucidate whether repetitive restructuring during reaction-regeneration cycling in structure insensitive reaction triggers more profound NP sintering as structure sensitive reactions. Aside from gaining foundational understanding, we will test smart gas sequence strategies to prevent rapid NP sintering, tailor-made for each reaction class (structure sensitive vs. insensitive).