Enhancing Thermocatalytic Activities via Up-shift of the d-Band Center of Exsolved Co-Ni-Fe Ternary Alloy Nanoparticles for Dry Reforming of Methane.

Dry reforming of methane (DRM) is a feasible solution to cope with the reduction of greenhouse gas under the Paris Convention's obligations, given that it adds value by converting trivial gases of CO2 and CH4 simultaneously into useful syngas. However, conventional Ni catalyst undergoes deactivation due to carbon coking and particle agglomeration. Here we demonstrate for the first time a highly efficient and durable DRM catalyst of exsolved Co-Ni-Fe ternary alloy nanoparticles on the layered perovskite PrBaMn1.7Co0.1Ni0.2O5+d produced by topotactic exsolution. This readily allows the generation of a larger number of exsolved nanoparticles, enhancing catalytic activity above those of Ni monometallic and Co-Ni bimetallic particles. The enhancement is achieved by the optimal up-shift of the d-band center of Co-Ni-Fe than those of Co-Ni and Ni meaning easier charge donation to the adsorbate. Furthermore, the exsolved catalyst shows exceptional stability with the continuous DRM operation for about 350 hours.