Design Of Catalytic Sites Research Articles

Constructing Asymmetric Cu Catalytic Sites for CO2 Electroreduction with Higher Selectivity to C2 Products.

The design of catalytic sites with tunable properties is considered a promising approach to advance the reduction of CO2 into valuable fuels and chemicals, as well as to achieve carbon neutrality. However, significant challenges remain in precisely constructing catalytic sites to adjust target reduction products. In this study, catalysts were derived from metal-organic frameworks (MOFs) with different coordination environments during the electrochemical CO2 reduction reaction (eCO2RR), referred to as Cu-N2O2 and Cu-N2O3, respectively. Higher selectivity towards the production of C2 products was exhibited by the Cu-N2O2-derived catalysts, characterized by asymmetric catalytic centers of Cu0 and Cu+, compared to the Cu-N2O3-derived catalysts, which contained only symmetric catalytic centers of Cu0 sites. This enhanced selectivity is attributed to the synergistic interaction between the Cu0 and Cu+ sites, facilitating the multi-electron transfer process and improving the activation of CO2. This study explores how the coordination environment affects the catalytic performance of catalysts derived from MOFs, providing valuable insights for the development of more effective catalysts aimed at CO2 reduction.

Photooxidase-Mimicking Nanovesicles with Superior Photocatalytic Activity and Stability Based on Amphiphilic Amino Acid and Phthalocyanine Co-Assembly.

Enzyme mimics have broad applications in catalysis and can assist elucidation of the catalytic mechanism of natural enzymes. However, challenges arise from the design of catalytic sites, the selection of host molecules, and their integration into active three-dimensional structures. Herein, we describe the development of a photooxidase mimic by synergetic molecular self-assembly. 9-Fluorenylmethyloxycarbonyl-l-histidine undergoes efficient co-assembly with phthalocyanine into nanovesicles with tunable particle size and membrane thickness. The obtained nanovesicles can be used as catalysts for reactive-oxygen-mediated photosensitive oxidation with improved efficiency and stability. This work highlights the co-assembly of simple building blocks into a supramolecular photocatalyst, which might give insight into possible evolutionary paths of photocatalytic membrane systems, and might allow facile transfer into photosensitive nanoreactors or artificial organelles.

Photooxidase‐Mimicking Nanovesicles with Superior Photocatalytic Activity and Stability Based on Amphiphilic Amino Acid and Phthalocyanine Co‐Assembly

AbstractEnzyme mimics have broad applications in catalysis and can assist elucidation of the catalytic mechanism of natural enzymes. However, challenges arise from the design of catalytic sites, the selection of host molecules, and their integration into active three‐dimensional structures. Herein, we describe the development of a photooxidase mimic by synergetic molecular self‐assembly. 9‐Fluorenylmethyloxycarbonyl‐l‐histidine undergoes efficient co‐assembly with phthalocyanine into nanovesicles with tunable particle size and membrane thickness. The obtained nanovesicles can be used as catalysts for reactive‐oxygen‐mediated photosensitive oxidation with improved efficiency and stability. This work highlights the co‐assembly of simple building blocks into a supramolecular photocatalyst, which might give insight into possible evolutionary paths of photocatalytic membrane systems, and might allow facile transfer into photosensitive nanoreactors or artificial organelles.

Heterogeneous Single-Atom Catalyst for Visible-Light-Driven High-Turnover CO2 Reduction: The Role of Electron Transfer.

Visible-light-driven conversion of CO2 into chemical fuels is an intriguing approach to address the energy and environmental challenges. In principle, light harvesting and catalytic reactions can be both optimized by combining the merits of homogeneous and heterogeneous photocatalysts; however, the efficiency of charge transfer between light absorbers and catalytic sites is often too low to limit the overall photocatalytic performance. In this communication, it is reported that the single-atom Co sites coordinated on the partially oxidized graphene nanosheets can serve as a highly active and durable heterogeneous catalyst for CO2 conversion, wherein the graphene bridges homogeneous light absorbers with single-atom catalytic sites for the efficient transfer of photoexcited electrons. As a result, the turnover number for CO production reaches a high value of 678 with an unprecedented turnover frequency of 3.77 min-1 , superior to those obtained with the state-of-the-art heterogeneous photocatalysts. This work provides fresh insights into the design of catalytic sites toward photocatalytic CO2 conversion from the angle of single-atom catalysis and highlights the role of charge kinetics in bridging the gap between heterogeneous and homogeneous photocatalysts.

Design of catalytic sites at oxide surfaces by metal-complex attaching and molecular imprinting techniques

This paper attempts to summarize our recent studies on the chemical design and characterization of catalytic sites at oxide surfaces such as Nb monomer, dimer and monolayer on SiO 2, Rh dimers on SiO 2, TiO 2, Al 2O 3, and MgO, and Au nanoparticles on TiO 2(1 1 0), prepared by using suitable metal-complex precursors in a molecular scale. The paper also reports performances of new molecular imprinting catalysts, SiO 2 overlayers/α-Al 2O 3 and Rh–SiO 2 overlayers/SiO 2, designed by surface molecular imprinting techniques.