Preparation of Sn-doped 2–3 nm Ni nanoparticles supported on SiO2 via surface organometallic chemistry for low temperature dry reforming catalyst: The effect of tin doping on activity, selectivity and stability

• Preparation of 2.2 ± 0.4 nm nickel nanoparticles supported on SiO2.
• Nickel was doped via SOMC with tin leading to 2–3 nm NiSnx particles (0 < x ≤ 0.32).
• Catalyst tested in CO2 reforming of CH4 at 773 K in kinetic conditions.
• Sn did not influence the catalysts selectivity, deactivation rate, coke formation.
• Tin doping results in a 3–4-fold decrease of surface Ni intrinsic activity.

Silica supported nickel nanoparticles of 2.2 ± 0.4 nm diameter were selectively doped with tin by surface organometallic chemistry while keeping the particle size nearly constant. The catalysts with various tin contents were doped and characterized by TEM, XRD and H2 chemisorption. In contrast to what is found at high temperature (≥973 K), dry reforming tests performed at 773 K and successive TPO and TEM analysis showed that tin neither influences the catalyst deactivation rate nor prevents coke formation, present in the form of encapsulating carbon. The nickel dopant does not influence either the selectivity, ruled by reverse water gas shift Thermodynamics, but was shown to have a 3–4-fold decrease of intrinsic activity of the available surface nickel, thus indicating that Sn has a negative effect on adjacent Ni atoms.

Figure optionsDownload high-quality image (141 K)Download as PowerPoint slide