Yiwei Zhou

Bio: Yiwei Zhou is an academic researcher from Tianjin University of Technology. The author has contributed to research in topics: Visible spectrum & Yield (engineering). The author has co-authored 1 publications.

Glaser coupling- and Sonogashira coupling-control over CuxO nanoparticles/carbon nanotube by switching visible-light off and on

Abstract: Utilizing CuxO nanoparticles supported on carbon nanotube as catalyst, visible-light could efficiently transform Glaser homo-coupling into Sonogashira cross-coupling. The isolated Sonogashira product yield is up to 0.58 mmol (sel. 97%) under visible-light irradiation while the Glaser product achieves 0.45 mmol (sel. 92%) in the dark for phenylacetylene and iodobenzene. We also discover that the active species under light irradiation is different from that in the dark. The visible light-driven adsorption of aromatic iodides on CuxO nanoparticles and light-excited copper(I) phenylacetylide intermediates together enables the high selectivity of Sonogashira product. The synergistic effect between Cu(II) and Cu(I) acetylide dimer complex enhances the Glaser product yield in the dark.

Thermo-photo catalysis: a whole greater than the sum of its parts.

Abstract: Thermo-photo catalysis, which is the catalysis with the participation of both thermal and photo energies, not only reduces the large energy consumption of thermal catalysis but also addresses the low efficiency of photocatalysis. As a whole greater than the sum of its parts, thermo-photo catalysis has been proven as an effective and promising technology to drive chemical reactions. In this review, we first clarify the definition (beyond photo-thermal catalysis and plasmonic catalysis), classification, and principles of thermo-photo catalysis and then reveal its superiority over individual thermal catalysis and photocatalysis. After elucidating the design principles and strategies toward highly efficient thermo-photo catalytic systems, an ample discussion on the synergetic effects of thermal and photo energies is provided from two perspectives, namely, the promotion of photocatalysis by thermal energy and the promotion of thermal catalysis by photo energy. Subsequently, state-of-the-art techniques applied to explore thermo-photo catalytic mechanisms are reviewed, followed by a summary on the broad applications of thermo-photo catalysis and its energy management toward industrialization. In the end, current challenges and potential research directions related to thermo-photo catalysis are outlined.

Plasmonic heterogeneous catalysis for organic transformations

Abstract: Plasmonic catalysis has been recognised as a promising alternative to many conventional thermal catalytic processes in organic synthesis. In addition to their high activity in fine chemical synthesis, plasmonic photocatalysts are also able to maintain control of selectivity under mild conditions by utilising visible-light as an energy source. This review provides an overview of the recent advances in organic transformations with plasmonic metal nanostructures, including selective reduction, selective oxidation, cross-coupling and addition reactions. We also summarize the photocatalysts and catalytic mechanisms involving surface plasmon resonance. Finally, control of reaction pathway and strategies for tailoring product selectivity in fine chemical synthesis are discussed. • A summary of the recent progress in plasmonic photocatalysis for organic transformation. • Reaction types, plasmonic photocatalysts and corresponding LSPR mechanisms involved are categorized. • The strategies for tailoring reaction pathway and product selectivity in organic transformation are discussed.

Cu-Ce Bimetallic Metal-Organic Framework-Derived, Oxygen Vacancy-Boosted Visible Light-Active Cu2O-CeO2/C Heterojunction: An Efficient Photocatalyst for the Sonogashira Coupling Reaction.

Abstract: The development of an economical transition metal-based catalyst for photocatalytic carbon-carbon coupling reactions is aspiring. Herein, a Cu-Ce metal-organic framework (MOF) was synthesized and carbonized to produce bimetallic Cu2O-CeO2/C, which was utilized in the Sonogashira cross-coupling reaction. The defects and oxygen vacancies in the catalyst were characterized by X-ray photoelectron spectroscopy and Raman spectroscopy, while the nature of Cu was characterized by H2-TPR analysis. The defect-induced MOF-derived Cu-Ce heterojunction created more oxygen vacancies (OV) in CeO2, revealing the high photocatalytic activity. The Cu-Ce heterojunction (Cu2O-CeO2/C) formed a Cu(I)-phenylacetylide active complex and exhibited higher catalytic activity for the visible light-induced Sonogashira cross-coupling reaction. 25%Cu2O-CeO2/C offered 93.8% phenylacetylene conversion with a 94.2% Sonogashira product selectivity by using household light-emitting diodes. No discernible activity loss was observed from the recycling of the catalyst. Based on catalytic activity, control reactions, and physicochemical and optoelectronic characterization, the structure-activity relationship was established and a reaction mechanism was proposed. Replacement of the costly Pd metal-based catalyst with a cheap Cu2O-CeO2-based catalyst for the synthesis of commercially important compounds with a sustainable visible light-induced catalytic process will be highly attractive to chemists and industrialists.

Light‐Assisted Ullmann Coupling of Phenols and Aryl Halides: The Synergetic Effect Between Plasmonic Copper Nanoparticles and Carbon Nanotubes from Various Sources

Abstract: Utilizing light and plastic wastes as resources to turn the wasted phenols and hazardous aryl halides into value added chemicals seems to be an attractive idea for alleviating the energy crisis and environmental problems. In this work, plasmonic copper nanoparticles (Cu NPs) were loaded onto carbon nanotubes (CNTs) from various sources including commercial CNTs and those derived from plastic wastes. Under visible-light irradiation, the catalyst could efficiently convert phenols and aryl halides to diaryl ethers. Similar with commercial CNTs, excellent activity is also achieved when utilizing CNTs derived from different kinds of plastic wastes as support for the system. Further investigation shows that the visible-light irradiation and light-excited plasmonic Cu NPs are necessary to inhibit the phenol degradation on CNTs and in turn promote the cross-coupling of phenol and aryl halides. Compared with metal oxides and other carbon materials, the excellent capability of CNTs to absorb light, to convert light to heat, and to adsorb both two reactants simultaneously are critical to enhance the activity of Cu NPs, achieving high yields of diaryl ethers. This study could provide a novel strategy for catalyst design and generate a more economically sustainable process.