High pyrocatalytic properties of pyroelectric BaTiO₃ nanofibers loaded by noble metal under room-temperature thermal cycling

In this work, an unambiguous pyroelectrically-induced pyrocatalysis in hydrothermally-synthesized BaTiO₃ (BTO) nanofibers with or without noble metal loading (BTO@Ag and BTO@Pd) is found and its application for the decomposition of Rhodamine B dye under thermal cycling near room-temperature is also developed. The pyrocatalytic decomposition ratios of BTO, BTO@Ag and BTO@Pd are ~ 48%, ~ 92% and ~ 95%, respectively, under 72 cold-hot (30–52 °C) thermal cycles. In the pyrocatalytic process, the detected main active species are holes, hydroxyl radicals and superoxide radicals. The enhanced pyrocatalysis is attributed to noble metals that trap the transferred electrons from the BTO surface, promoting charge separation. No obvious loss of pyrocatalytic activity is observed after 5 cycles, indicating good stability of BTO@Ag and BTO@Pd nanofibers. The enhanced pyrocatalytic performance makes BTO@Ag and BTO@Pd nanofibers potential in purifying dye waste pollution through utilizing cold-hot fluctuation thermal energy.