The reverse water gas shift (rWGS) reaction has great potential to contribute to the current efforts for a transition towards a sustainable energy future. It has the potential to drastically reduce the global CO2 output as it can utilize CO2 as an abundant and renewable carbon source. Additionally, rWGS is among the catalytic reactions with the highest readiness level for technological implementation.
In industrial processes rWGS is operated at high reaction temperatures (700 – 900 °C) as then the efficiency is maximized. These harsh conditions are extremely demanding in terms of used catalyst materials, strongly limiting the number of suitable candidates. Typical materials are Ni/ZrO2 based, but they suffer deactivation due to sintering (agglomeration of Ni). Hence great efforts are made for development of novel catalysts for rWGS.
To achieve excellent rWGS performance, catalytically active nanoparticles that are evenly distributed on an active support are crucial. An extremely versatile material class that exhibits the desired properties are perovskite-type oxides. They allow for a materials design approach and can easily be doped with highly active elements (e.g. Ni or Co). Upon controlled reduction or during reaction, these dopants leave the perovskite lattice and diffuse through the material to form metal nanoparticles on the surface where they can greatly enhance the rWGS reactivity. Additionally, the perovskite itself is highly active for CO2 activation (by providing oxygen vacancies for efficient CO2 adsorption) and is stable at high reaction temperatures. This makes them ideal rWGS catalysts.
In first lab-measurements we have demonstrated that our perovskite catalysts can outperform standard industrial catalyst. The next step towards industrial applicability is the development of our material on an industrial scale. For this the synthesis route has to be modified and scaled up, followed by catalytic performance tests in an industrial test reactor.
