Hydrophobic Fe‐Based Catalyst Derived from Prussian Blue for Enhanced Photothermal Conversion of Syngas to Light Olefins

Abstract

Although there are many promising works in the field of Fischer–Tropsch synthesis (FTS), it is still a huge challenge to achieve the rational design of FTS catalysts for excellent selectivity toward light olefins with a high olefins/paraffins ratio (o/p ratio). Herein, a hydrophobic core–shell Fe‐based FTS catalyst is developed by calcination and hydrophobic modification of polyvinylpyrrolidone (PVP)‐decorated Prussian blue (PB, Fe4[Fe(CN)6]3) precursor. The hydrophobic modification is achieved by using trimethylchlorosilane (TMCS) as the hydrophobic agent. Under light irradiation and near ambient pressure (0.18 MPa), compared with the catalyst without the hydrophobic surface to mainly convert CO to valueless CO2, the optimal catalyst delivers excellent selectivity of 48.0% for value‐added light olefins (C2–4 = ) with a high o/p ratio of 10.1 but low selectivity for CO2 at a CO conversion of 22.6%. The excellent FTS performance can be attributed to that the hydrophobic surface of the catalyst regulates the chemical reaction pathway, which promotes the CO hydrogenation but suppresses the conversion of CO to CO2. The study demonstrates that a rationally designed functional surface of a catalyst can govern the reaction pathway along value‐added solar‐to‐chemicals conversion.

Shedding Light on Solar Olefin Synthesis: Advances and Perspectives

“…Notably, this system exhibited outstanding CO hydrogenation performance, yielding an olefin (C 2–4= ) selectivity of 36.0% and an olefin/paraffin ratio of 6.1 at a CO conversion rate of 15.4%. This outcome suggests that the conversion of CO to light olefins and other products follows a photothermal pathway, a phenomenon also observed in catalysts such as CoAl-LDH-developed catalyst, Ni/MnO, titania-supported Ni 2 P/Ni, ruthenium–cobalt single atom alloy catalyst, and the hydrophobic core–shell Fe/Fe 3 C-c, and Fe 5 C 2 . The corresponding activity has been summarized in Table .…”

Recent Advances Hydrogenation of Carbon Dioxide to Light Olefins over Iron-Based Catalysts via the Fischer–Tropsch Synthesis

“…Modification of iron-based catalysts with hydrophobic substances to accelerate the diffusion of H 2 O generated on the catalyst surface is a promising strategy. Shi et al 141 designed an iron-based catalyst with trimethylchlorosilane (TMCS) as the hydrophobic agent and polyvinylpyrrolidone (PVP)-modified Prussian blue (PB, Fe 4 [Fe(CN) 6 ] 3 ) as precursor. The chemical reaction pathways were modulated by the hydrophobic surface of the catalysts, and a 48% selectivity for low-carbon olefins was achieved.…”

Stabilized ε-Fe2C catalyst with Mn tuning to suppress C1 byproduct selectivity for high-temperature olefin synthesis

“…However, issues such as high CH 4 or CO 2 selectivity and limited olefin selectivity often compromise the carbon efficiency and economic viability of these catalysts. Therefore, there is a growing demand to develop efficient catalysts that can achieve high olefin selectivity while minimizing C1 byproduct formation 8 , 9 .…”