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Methanol is a major fuel and chemical feedstock currently produced from syngas, a CO/CO2/H2 mixture. Herein we identify formate binding strength as a key parameter limiting the activity and stability of known catalysts for methanol synthesis in the presence of CO2. We present a molybdenum phosphide catalyst for CO and CO2 reduction to methanol, which through a weaker interaction with formate, can improve the activity and stability of methanol synthesis catalysts in a wide range of CO/CO2/H2 feeds. MoP‐ed up: MoP is a new catalyst for CO and CO2 hydrogenation to methanol. By stabilizing only the monodentate binding configuration of formate, the phosphide is able to circumvent the (scaling) relationship between the necessary ability of the catalyst to bind oxygen‐containing intermediates and catalyst deactivation resulting from high formate coverage in the presence of CO2. [ABSTRACT FROM AUTHOR]

Methanol is a major fuel and chemical feedstock currently produced from syngas, a CO/CO2/H2 mixture. Herein we identify formate binding strength as a key parameter limiting the activity and stability of known catalysts for methanol synthesis in the presence of CO2. We present a molybdenum phosphide catalyst for CO and CO2 reduction to methanol, which through a weaker interaction with formate, can improve the activity and stability of methanol synthesis catalysts in a wide range of CO/CO2/H2 feeds. MoP‐ed up: MoP is a new catalyst for CO and CO2 hydrogenation to methanol. By stabilizing only the monodentate binding configuration of formate, the phosphide is able to circumvent the (scaling) relationship between the necessary ability of the catalyst to bind oxygen‐containing intermediates and catalyst deactivation resulting from high formate coverage in the presence of CO2. [ABSTRACT FROM AUTHOR]

Molybdenum phosphide (MoP) catalyzes the hydrogenation of CO, CO2, and their mixtures to methanol, and it is investigated as a high-activity catalyst that overcomes deactivation issues (e.g., formate poisoning) faced by conventional transition metal catalysts. MoP as a new catalyst for hydrogenating CO2 to methanol is particularly appealing for the use of CO2 as chemical feedstock. Herein, we use a colloidal synthesis technique that connects the presence of MoP to the formation of methanol from CO2, regardless of the support being used. By conducting a systematic support study, we see that zirconia (ZrO2) has the striking ability to shift the selectivity towards methanol by increasing the rate of methanol conversion by two orders of magnitude compared to other supports, at a CO2 conversion of 1.4% and methanol selectivity of 55.4%. In situ X-ray Absorption Spectroscopy (XAS) and in situ X-ray Diffraction (XRD) indicate that under reaction conditions the catalyst is pure MoP in a partially crystalline phase. Results from Diffuse Reflectance Infrared Fourier Transform Spectroscopy coupled with Temperature Programmed Surface Reaction (DRIFTS-TPSR) point towards a highly reactive monodentate formate intermediate stabilized by the strong interaction of MoP and ZrO2. This study definitively shows that the presence of a MoP phase leads to methanol formation from CO2, regardless of support and that the formate intermediate on MoP governs methanol formation rate. [ABSTRACT FROM AUTHOR]

• Ni-Ga intermetallic catalysts for methanol synthesis from CO 2 were modified with Au, Cu and Co. • Au and Cu promote methanol synthesis activity. • Au-Ni-Ga demonstrates the highest activity. • Ni 3 Ga is the dominant intermetallic phase post catalysis. Ni-Ga and M-Ni-Ga (M = Au, Co, Cu) catalysts were evaluated for methanol synthesis from CO 2 at 10 bar and 200−270 °C. The following trend in turnover frequency (TOF) for CO 2 hydrogenation was observed: AuNiGa > CuNiGa > NiGa > CoNiGa, where TOF increased with decreasing catalyst affinity for CO. The presence of a third metal was found to influence both the formation of the Ni-Ga intermetallic phase as well as the number of available sites for CO chemisorption. Phase formation, catalyst composition and stability were evaluated using therm ogravimetric analysis (TGA), X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning transmission electron microscopy and energy dispersive X-ray spectroscopy (STEM-EDX). Au-Ni-Ga, which showed a nearly 4-fold improvement in TOF at 263 °C and 10 bar compared to Ni-Ga, consisted of Ni 3 Ga particles decorated with Au, as evidenced by post catalysis characterization. [ABSTRACT FROM AUTHOR]