Large-scale Preparation of Black CeO_x with Stable Oxygen Vacancies

Oxygen vacancy in ceria is a crucial regulation factor for modifying materials. The reduced oxygen vacancy will undergo rapid recombination and deactivation due to the imbalance perturbation of active oxygen species, thereby restricting their larger-scale application. In this work, we proposed a strategy to stabilize oxygen vacancy in four black CeO_x(Si) (0<x<2) by quartz sand doping reduction. The formation of a Ce-O_v-Si (O_v denoted as oxygen vacancy) interface, instrumental in constructing stable oxygen vacancies, is facilitated by rich hydroxyl groups. Characterizations of CeO_x(Si) reveal that the heterogeneous hydrogen at the Ce-O-Si interface encourages the lattice distortion in ceria to obtain stable oxygen vacancies. Guided by the reusable feature, quartz sand doping reduction is a facile and feasible strategy to stabilize the oxygen vacancy of black CeO_x for advanced materials on a large scale.