Lotus seedpods-inspired, highly efficient and durable Ce-doped modified manganese-based catalysts for enhanced formaldehyde removal at room temperature

Formaldehyde (HCHO) release is a long process due to indoor decoration and furniture, which poses a serious threat to human health. Yet it is still a great challenge to remove formaldehyde efficiently at room temperature for a long time. Herein, inspired by porous lotus seedpods, cerium-doped manganese-based catalysts supported on diatomaceous earth (MnXCeY-DM) with high efficiency for formaldehyde removal were successfully prepared by co-precipitation and coordination complexation processes. The results showed that the transition metal oxides on the surfaces of both catalysts before and after doping with Ce were not highly crystalline and well-dispersed. The introduction of Ce reduced the agglomeration of the excessive metal oxides on the surfaces. Noteworthy, Ce doping can bring larger porosity, specific surface area, and more nano effects, which can accelerate the oxidative breakdown of formaldehyde. The absorption and reaction efficiency of the Mn20Ce5-DM catalyst reached 100% for 12 h at an HCHO concentration of 2 mg/m 3 at room temperature, which was 4.67% higher than that of the Ce-undoped catalyst. The final removal efficiency of Mn20Ce5-DM reached 78.05% even after five cycles. At room temperature, diatomaceous earth (DM) has a strong adsorption function, and the addition of Ce element promotes the oxidation process of HCHO, which strengthens the synergistic effect of the decomposition of HCHO. This research provides an excellent strategy to improve the HCHO degradation efficiency and persistence of manganese-based catalysts at room temperature.