Improvement of photocatalytic ammonia production of cobalt ferrite nanoparticles utilizing microporous ZSM-5 type ferrisilicate zeolite

The development of decarbonized synthesis approaches is a critical step in the fabrication of ammonia, an indispensable chemical and a potential carbon-neutral energy carrier. In this regard, the photocatalytic production technology has gained ample attention as a sustainable alternative to energy-intensive and environmentally detrimental Haber-Bosch process. Here, we present cobalt ferrite nanoparticles supported on microporous ZSM-5 type ferrisilicate zeolite as a desirable novel photocatalyst for the ammonia generation. The zeolite introduced as a microporous support increasing the catalytically active sites. A straightforward one-pot sol-gel method was used to synthesize cobalt ferrite (CoFe₂O₄) and CoFe₂O₄/ferrisilicate (CF/FS) nanocomposites with various weight percentages (10, 25 and 50%) of CoFe₂O₄. The photocatalytic performances of the samples in the production of ammonia were investigated under visible light irradiation. The highest rate of NH₄⁺ production (484.74 µmol L^-1 h^-1) was achieved using the CF50%/FS photocatalyst. The distribution of < 50 nm-sized CoFe₂O₄ nanoparticles on the surface of the zeolite, as demonstrated by TEM images, and extensive BET surface areas are presented as convincing evidences for the improved photocatalytic activity paticularly in CF50%/FS photocatalyst.