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Perovskite-based catalysts for CO2 photoreduction reaction
No full textPerovskite-based catalysts for CO2 photoreduction reaction
I. Martin1*, G. Forghieri2, E. Ghedini2, I. Rossetti3, M. Signoretto2
1Functional Nanosystems, Italian Institute of Technology, Via Morego 30, 16163 Genoa, Italy
2Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice and INSTM RU of Venice, Via Torino 155, 30172 Venice, Italy
3Chemical Plants and Industrial Chemistry Group, Chemistry Department, University of Milan, CNR-SCITEC ans INSTM RU of Milan, Via C. Golgi 19, 20133 Milan, Italy
*Corresponding Author’s E-mail address: [email protected]
Introduction. The worrying rise in greenhouse gas emissions has led to the necessity of limiting the consumption of fossil sources on one hand, and on the other to develop new technologies for capturing, storing and utilising these gases [1]. In this perspective, CO2 photoreduction, paired with water splitting, presents a great potential for the synthesis of fuels and other building block molecules of high value, e.g. methane (CH4), carbon monoxide (CO) and other C1-based products [2]. To develop an effective and selective photocatalytic system, the perovskite barium titanate (BaTiO3) was chosen as a new promising photoactive material with respect to other common photocatalysts, e.g. titanium dioxide (TiO2) and zinc oxide (ZnO). Copper (II) oxide was introduced as a co-catalysts to hinder charge recombination [3], enhacing the activity and selectivity of the perovskite.
Experimental/methodology. BaTiO3 was synthesized by hydrothermal method, modified from literature [4], and was compared with commercial TiO2 (Degussa P25, Evonik) and a lab-synthesized ZnO (synthesized by precipitation [5]). CuO was synthesized by hydrothermal method [6] and introduced as a co-catalyst by impregnation (2.5 wt%) on BaTiO3, TiO2 and ZnO. The photocatalysts were tested in a gas and liquid phase.
Results and discussion. Experiments performed in gas phase resulted in the production of methane and hydrogen, in accordance with the proposed reaction mechanism [7]. Pristine BaTiO3 was less active with respect to TiO2 (79 vs 104 μmol gcat-1 h-1 of CH4, respectively), but the presence of CuO both improved both its activty and resulted in a minor H2 production with respect to CuO/TiO2 (221 vs 169 μmol gcat-1 h-1 of CH4 and 239 vs 414 μmol gcat-1 h-1 of H2, repectively). Experiments performed in liquid phase under neutral pH resulted in the production of formic acid and methanol [7], whereas under basic pH only HCOOH was detected. The basic enviroment also provided a ten-fold total productivity in C-based molecules with respect to pH 7. Under these reaction conditions, the materials showed similar activity and the introduction of CuO did not lead to significant improvements. Thus it is possible to argue that CO2 photoreduction performed in liquid phase is driven by reaction conditions, whilst in gas phase the choice of the appropriate photocatalyst can redirect the activity and selectivity of the reaction.
References
[1] Riahi, K. et al. IPCC, 2022: Mitigation of Climate Change, Contribution of Working Group III to the Sixth Assessment Report of Intergovernmental Panel on Climate Change, Cambridge, UK and New York, NY, USA 2022.
[2] Gür, T.M. Progress in Energy and Combustion Science 2022, 89, 1009657.
[3] Nogueira, A.E. Catalyis Communications 2020, 137, 105929.
[4] Kwak, B.S. and Kang, M. Journal of Nanoscience and Nanotechnology 2017, 17, 7351-7357.
[5] Thompson, W.A. et al. RSC Advances 2019, 9, 21660.
[6] Chandrasekar, M. et al. Journal of Kind Saud University – Science 2022, 34, 101831.
[7] Olivo, A. et al. Energies 2017, 10, 1394
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No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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