Visible-Light Photocatalytic Co2 Reduction Using Metal-Organic Framework Derived Ni(Oh)(2) Nanocages: A Synergy From Multiple Light Reflection, Static Charge Transfer, And Oxygen Vacancies

The development of redox-targeting co-catalysts is one of the important tasks in realizing hybrid photocatalytic systems for CO2 reduction reaction (CO2 RR), which has been sought after as a promising way to mitigate the energy and environmental crisis. In this study, hollow nickel hydroxide nanocages are successfully fabricated via an ion-assisted etching protocol using ZIF-8 as the structural template, and they are used as cocatalysts along with a molecular photosensitizer and sacrificial electron donor for reducing visible-light CO2. A remarkable CO evolution rate of 1.44 x 10(5) mu mol.g(co-cat)(-1).h(-1), a CO selectivity of 96.1%, and a quantum efficiency of 2.50% are achieved using the optimal cavernous structure with thin walls, attributing to the significantly improved light harvest owing to multiple light reflection and scattering, static electron transfer, abundant surface oxygen vacancies, as well as coherent energy flow among well-aligned band levels. This study highlights the design and development of hollow entities toward CO2 RR and provides insights into the structure-mediated photocatalytic response.