Tuning the color of high-karat gold in Au-TiO2 nanoparticle composites all the way to black
Lidia Rossi,
Endre Horváth,
Tianyi Wang,
Claudio Grimaldi,
Andrzej Sienkiewicz,
Bence Gábor Márkus,
David Beke,
László Forró
Affiliations
Lidia Rossi
Laboratory of Physics of Complex Matter, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
Endre Horváth
Laboratory of Physics of Complex Matter, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
Tianyi Wang
Stavropoulos Center for Complex Quantum Matter, Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN 46556, USA
Claudio Grimaldi
Laboratory of Physics of Complex Matter, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
Andrzej Sienkiewicz
Laboratory of Physics of Complex Matter, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; ADSresonances Sàrl, Martigny, Switzerland
Bence Gábor Márkus
Stavropoulos Center for Complex Quantum Matter, Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN 46556, USA; Corresponding author
David Beke
Stavropoulos Center for Complex Quantum Matter, Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN 46556, USA; Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Budapest, Hungary; Corresponding author
László Forró
Laboratory of Physics of Complex Matter, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Stavropoulos Center for Complex Quantum Matter, Department of Physics and Astronomy, University of Notre Dame, Notre Dame, IN 46556, USA; Corresponding author
Summary: For centuries, artisans have harnessed gold nanoparticles to imbue their creations with the vibrant hues that captivate the eye through interactions with visible light. In modern times, these distinct optoelectronic characteristics have pivoted toward the forefront of innovative technologies, finding their niche in advanced applications from solar energy to medicine, overshadowing their artistic heritage. This investigation reimagines the utilitarian scope of gold by innovating the optical characteristics of gold-titania nanostructures. This allows for an expanded palette of colors that retain the value of the precious metal. We employ nanostructured TiO2 in a high-pressure-high-temperature sintering technique that stabilizes Au nanoparticles, thwarting coalescence, and Oswald ripening. Further refinement is possible by engineering TiO2 color centers through the introduction of oxygen vacancies and Ti3+ ions, which aid in creating an opulent high-karat black-gold, but preserve the mechanical attributes essential to the integrity and function of the final product.
