Novel high surface area stainless steel wire mesh supported Ni0.7Zn0.3O solid solution prepared by room temperature sacrificial template accelerated hydrolysis. Application in the production of hydrogen from methanol

Abstract

This work describes for the first time the room-temperature synthesis of a high surface area Ni0.7Zn0.3O solid solution by sacrificial template accelerated hydrolysis. The synthesis employs a highly polar ZnO template supported on the surface of a stainless steel wire mesh (SSWM) that allows the material to be produced in a monolithic configuration. The resulting material has a large surface area of around 100 m2 g−1 and is obtained in a yield of up to 40 wt.% on the SSWM in the synthesis conditions employed in this work. Characterization of the material by TPR, XRD and XPS revealed that the solid solution is composed of an oxygen-defective bulk and a partially oxidized surface. As part of this study, the Ni0.7Zn0.3O solid solution has been tested for the first time as a catalyst, displaying high activity in both the methanol steam reforming and the methanol decomposition reactions. At temperatures below 400 °C the catalyst is not very selective in the methanol steam reforming reaction, and produces large amounts of CO. However, at more elevated temperatures the water gas shift reaction improves the hydrogen yield and the carbon selectivity towards CO2, especially over higher contact times. Despite some catalyst deactivation due to coke deposition, methanol decomposition occurs with high conversion degrees and hydrogen yields in the temperature range of 250–350 °C.