Enhanced photo-assisted thermal catalytic performance of Ni-doped Co3O4/stilbite composite fiber felt for formaldehyde purification

Herein, in-situ self-assembly of ZIF-67 derivative on the surface of stilbite and the doping of Ni ions into the Co 3 O 4 lattice were simultaneously achieved through a one-step calcination method. The obtained Ni-doped Co 3 O 4 /stilbite (Ni-Co-AS) exhibited efficient photo-assisted thermal catalytic purification of formaldehyde (HCHO). The results showed that after being regulated by Ni-doped, the Ni-Co-AS composite could achieve efficient photo-assisted thermal catalytic degradation of HCHO driven solely by light. The HCHO removal rate and mineralization rate could reach 93.04 % and 88.60 % within 3 h, respectively. In addition, in order to further improve the photothermal conversion performance of Ni-Co-AS, the composite fiber felt (Ni-Co-AS/F) was prepared from Ni-Co-AS. The conditional experiments show that thermal catalysis is the main mechanism in the photothermal catalytic degradation of formaldehyde by Ni-Co-AS/F. Compared to the pure thermal catalysis (180℃), the presence of light helps to reduce the reaction temperature (120℃) and plays a role in co-catalysis. Ni-Co-AS/F could achieve a higher mineralization rate than that of Ni-Co-AS composite (91.66 %) within 3 h due to the better dispersion and quantum transmission efficiency. In dynamic and long-term degradation experiments, the Ni-Co-AS/F exhibited excellent catalytic performance under the appropriate temperature (35 ± 0.5℃) and humidity (45 ± 3 %) required for the HCHO degradation. This work could effectively provide an efficient and sustainable catalytic material for air pollution control.