“…129 The metal nanoparticles, however, exhibit thermal instability and are prone to migration and coalescence during the catalytic process due to their high surface energy. Encapsulating metal nanoparticles in nano-shells or nano-pores, such as organometallic frameworks (MOFs), [130][131][132][133] covalent organic frameworks (COFs), 134 organic molecular cages, 75,[135][136][137] and amorphous porous organic polymers (POPs), [138][139][140] is expected to prevent the migration and coalescence of NPs, thereby improving their catalytic stability. 141 POC is a potential candidate for synthesizing and stabilizing NPs due to its unique spatial constraint effect.…”