Zinc Blende CoO as an Efficient CO Nondissociative Adsorption Site for Direct Synthesis of Higher Alcohols from Syngas

Monometallic Co0–Coδ+ catalysts have shown considerable potential in higher alcohol synthesis (HAS) direct from syngas, however, the alcohol selectivity and catalyst stability still need to be promoted. Here, we prepared a series of cobalt silicate hydroxide-derived catalysts and surprisingly obtained tetrahedrally coordinated zinc blende CoO (Z-CoO) during reduction and reaction. The nanoscale close interacted Co0-Z-CoO achieved an ROH selectivity of 64.4%, a higher alcohol (HA) selectivity of 43.6%, and a space time yield (STY) toward HA of 42.0 mmol·gCo–1·h–1, which outperformed most of the reported Co-based HAS catalysts. In addition, as a contrast, the commonly obtained rocksalt CoO (R-CoO) with octahedral structure was prepared. It is proved that Z-CoO serves as the CO nondissociative adsorption site, which exhibits a much stronger adsorption capability compared to R-CoO and Co2C, greatly facilitating the alcohol formation. Moreover, unlike the R-CoO, there were barely no phase transition of Z-CoO during HAS reaction, contributing to the catalyst stability over 550 h reaction. This work offers a facile preparation method and insights of zinc blende CoO as promising high-performance active sites for HAS.