Synergistic polarity interaction and structural reconstruction in Bi2MoO6/C3N4 heterojunction for enhancing piezo-photocatalytic nitrogen oxidation to nitric acid

Abstract

Constructing heterojunctions has emerged as a widely embraced strategy for augmenting piezo-photocatalytic activities. However, the synergistic pressure response, the construction of charge transfer, polar direction sites and active site are often left in the basket. Here, the carboxylated C3N4 and Bi2MoO6 S-scheme heterostructure was elaborately designed for piezo-photocatalytic nitrogen oxidation towards nitric acid. Extensive research evidence proves that Bi-COOH interaction between Bi2MoO6 and g-C3N4 leads to the occurrence of polarity interaction and structural reconstruction. Those initiatives facilitate the efficient distribution of charges and acts as a pathway for carrier migration, thereby promoting charge transfer and the large intrinsic dipole moment. Furthermore, the combination of polarity interaction and structural reconstruction strengthens N2 polarization and electron transfer, facilitating the breaking of NN bonds and reducing activation energy. Consequently, the optimal BCO-3 catalyst revealed outstanding nitric acid production rates of 5930 μg g−1 h−1 under the stimulation of ultrasonic and light illumination, which is 3.66 times higher than that of C3N4-Bi2MoO6 heterostructure and superiors to various piezo-photocatalysts. Our research endeavors present promising prospects for the design of advanced catalysts and contribute to a profound comprehension of molecular activation processes in heterojunction.