Shanmugam, V. et al. A review of the synthesis, properties, and applications of 2D materials. Part. Part. Syst. Charact. 39, 2200031 (2022).Li, N., Zhao, P. & Astruc, D. Anisotropic gold nanoparticles: synthesis, properties, applications, and toxicity. Angew. Chem. Int. Ed. 53, 1756–1789 (2014).Article 
CAS 

Google Scholar 
Miura, H. et al. Diverse alkyl–silyl cross-coupling via homolysis of unactivated C (sp3)–O bonds with the cooperation of gold nanoparticles and amphoteric zirconium oxides. J. Am. Chem. Soc. 145, 4613–4625 (2023).Article 
CAS 
PubMed 

Google Scholar 
Tada, H. Overall water splitting and hydrogen peroxide synthesis by gold nanoparticle-based plasmonic photocatalysts. Nanoscale Adv. 1, 4238–4245 (2019).Article 
CAS 
PubMed 
PubMed Central 

Google Scholar 
Hong, X., Tan, C., Chen, J., Xu, Z. & Zhang, H. Synthesis, properties and applications of one- and two-dimensional gold nanostructures. Nano Res. 8, 40–55 (2015).Article 
CAS 

Google Scholar 
Goldsmith, B. R. et al. Two-to-three dimensional transition in neutral gold clusters: the crucial role of van der Waals interactions and temperature. Phys. Rev. Mater. 3, 016002 (2019).Article 
CAS 

Google Scholar 
Pyykko, P. Relativistic effects in structural chemistry. Chem. Rev. 88, 563–594 (1988).Article 
CAS 

Google Scholar 
Fernández, E. M., Soler, J. M., Garzón, I. L. & Balbás, L. C. Trends in the structure and bonding of noble metal clusters. Phys. Rev. B 70, 165403 (2004).Article 

Google Scholar 
Häkkinen, H., Moseler, M. & Landman, U. Bonding in Cu, Ag, and Au clusters: relativistic effects, trends, and surprises. Phys. Rev. Lett. 89, 033401 (2002).Article 
PubMed 

Google Scholar 
Baffou, G., Cichos, F. & Quidant, R. Applications and challenges of thermoplasmonics. Nat. Mater. 19, 946–958 (2020).Article 
CAS 
PubMed 

Google Scholar 
Graziano, G. All-plasmonic water splitting. Nat. Nanotechnol. 16, 1053 (2021).Article 
CAS 
PubMed 

Google Scholar 
Ye, S. et al. Sub-nanometer thick gold nanosheets as highly efficient catalysts. Adv. Sci. 6, 1900911 (2019).Article 
CAS 

Google Scholar 
Ono, S. Dynamical stability of two-dimensional metals in the periodic table. Phys. Rev. B 102, 165424 (2020).Article 
CAS 

Google Scholar 
Koskinen, P. & Korhonen, T. Plenty of motion at the bottom: atomically thin liquid gold membrane. Nanoscale 7, 10140–10145 (2015).Article 
CAS 
PubMed 

Google Scholar 
Yang, L.-M., Dornfeld, M., Frauenheim, T. & Ganz, E. Glitter in a 2D monolayer. Phys. Chem. Chem. Phys. 17, 26036–26042 (2015).Article 
CAS 
PubMed 

Google Scholar 
Yang, L.-M., Ganz, A. B., Dornfeld, M. & Ganz, E. Computational study of quasi-2D liquid state in free standing platinum, silver, gold, and copper monolayers. Condens. Matt. 1, 1 (2016).Article 

Google Scholar 
Nevalaita, J. & Koskinen, P. Stability limits of elemental 2D metals in graphene pores. Nanoscale 11, 22019–22024 (2019).Article 
CAS 
PubMed 

Google Scholar 
Campbell, C. T. Ultrathin metal films and particles on oxide surfaces: structural, electronic and chemisorptive properties. Surf. Sci. Rep. 27, 1–111 (1997).Article 
CAS 

Google Scholar 
Norrman, S., Andersson, T., Granqvist, C. & Hunderi, O. Optical properties of discontinuous gold films. Phys. Rev. B 18, 674 (1978).Article 
CAS 

Google Scholar 
Wang, L. et al. Two-dimensional gold nanostructures with high activity for selective oxidation of carbon–hydrogen bonds. Nat. Commun. 6, 6957 (2015).Article 
CAS 
PubMed 

Google Scholar 
Wang, X., Wang, C., Chen, C., Duan, H. & Du, K. Free-standing monatomic thick two-dimensional gold. Nano Lett. 19, 4560–4566 (2019).Article 
CAS 
PubMed 

Google Scholar 
Zhao, L., Ta, H. Q., Mendes, R. G., Bachmatiuk, A. & Rummeli, M. H. In situ observations of freestanding single‐atom‐thick gold nanoribbons suspended in graphene. Adv. Mater. Interfaces 7, 2000436 (2020).Article 
CAS 

Google Scholar 
Bhandari, S. et al. Two-dimensional gold quantum dots with tunable bandgaps. ACS Nano 13, 4347–4353 (2019).Article 
CAS 
PubMed 

Google Scholar 
Forti, S. et al. Semiconductor to metal transition in two-dimensional gold and its van der Waals heterostack with graphene. Nat. Commun. 11, 2236 (2020).Article 
CAS 
PubMed 
PubMed Central 

Google Scholar 
Natarajan, G., Mathew, A., Negishi, Y., Whetten, R. L. & Pradeep, T. A unified framework for understanding the structure and modifications of atomically precise monolayer protected gold clusters. J. Phys. Chem. C 119, 27768–27785 (2015).Article 
CAS 

Google Scholar 
Sharma, S. K., Pasricha, R., Weston, J., Blanton, T. & Jagannathan, R. Synthesis of self-assembled single atomic layer gold crystals-goldene. ACS Appl. Mater. Interfaces 14, 54992–55003 (2022).Article 
CAS 
PubMed 
PubMed Central 

Google Scholar 
Fashandi, H. et al. Synthesis of Ti3AuC2, Ti3Au2C2 and Ti3IrC2 by noble metal substitution reaction in Ti3SiC2 for high-temperature-stable Ohmic contacts to SiC. Nat. Mater. 16, 814–818 (2017).Lei, X. & Lin, N. Structure and synthesis of MAX phase materials: a brief review. Crit. Rev. Solid State Mater. Sci. 47, 736–771 (2022).Article 
CAS 

Google Scholar 
Lim, K. R. G. et al. Fundamentals of MXene synthesis. Nat. Synth. 1, 601–614 (2022).Article 

Google Scholar 
Naguib, M. et al. Two‐dimensional nanocrystals produced by exfoliation of Ti3AlC2. Adv. Mater. 23, 4248–4253 (2011).Article 
CAS 
PubMed 

Google Scholar 
Sun, P. et al. Unexpected catalytic activity of nanorippled graphene. Proc. Natl Acad. Sci. USA 120, e2300481120 (2023).Article 
CAS 
PubMed 
PubMed Central 

Google Scholar 
Li, R. et al. Study on the assembly structure variation of cetyltrimethylammonium bromide on the surface of gold nanoparticles. ACS Omega 5, 4943–4952 (2020).Article 
CAS 
PubMed 
PubMed Central 

Google Scholar 
International Organization for Standardization. Surface Chemical Analysis—X-ray Photoelectron Spectrometers—Calibration of Energy Scales. ISO 15472:2010 (ISO, 2020).Näslund, L.-Å., Persson, P. O. & Rosen, J. X-ray photoelectron spectroscopy of Ti3AlC2, Ti3C2Tz, and TiC provides evidence for the electrostatic interaction between laminated layers in MAX-phase materials. J. Phys. Chem. C 124, 27732–27742 (2020).Article 

Google Scholar 
Svanidze, E. et al. An itinerant antiferromagnetic metal without magnetic constituents. Nat. Commun. 6, 7701 (2015).Article 
CAS 
PubMed 

Google Scholar 
Magnuson, M. et al. Electronic structure and chemical bonding in Ti2AlC investigated by soft x-ray emission spectroscopy. Phys. Rev. B 74, 195108 (2006).Article 

Google Scholar 
Wertheim, G., DiCenzo, S. & Youngquist, S. Unit charge on supported gold clusters in photoemission final state. Phys. Rev. Lett. 51, 2310 (1983).Article 
CAS 

Google Scholar 
DiCenzo, S., Berry, S. & Hartford, E. Jr Photoelectron spectroscopy of single-size Au clusters collected on a substrate. Phys. Rev. B 38, 8465 (1988).Article 
CAS 

Google Scholar 
de Anda Villa, M. et al. Assessing the surface oxidation state of free-standing gold nanoparticles produced by laser ablation. Langmuir 35, 11859–11871 (2019).Article 
PubMed 

Google Scholar 
Klyushin, A. Y., Rocha, T. C., Hävecker, M., Knop-Gericke, A. & Schlögl, R. A near ambient pressure XPS study of Au oxidation. Phys. Chem. Chem. Phys. 16, 7881–7886 (2014).Article 
CAS 
PubMed 

Google Scholar 
Juodkazis, K., Juodkazyt, J., Jasulaitien, V., Lukinskas, A. & Šebeka, B. XPS studies on the gold oxide surface layer formation. Electrochem. Commun. 2, 503–507 (2000).Article 
CAS 

Google Scholar 
Krozer, A. & Rodahl, M. X-ray photoemission spectroscopy study of UV/ozone oxidation of Au under ultrahigh vacuum conditions. J. Vacuum Sci. Technol. A 15, 1704–1709 (1997).Article 
CAS 

Google Scholar 
Kondo, Y. & Takayanagi, K. Gold nanobridge stabilized by surface structure. Phys. Rev. Lett. 79, 3455 (1997).Article 
CAS 

Google Scholar 
Fashandi, H. et al. Single-step synthesis process of Ti3SiC2 ohmic contacts on 4H-SiC by sputter-deposition of Ti. Scr. Mater. 99, 53–56 (2015).Article 
CAS 

Google Scholar 
Musolino, M. et al. Paving the way toward the world’s first 200mm SiC pilot line. Mater. Sci. Semicond. Process. 135, 106088 (2021).Article 
CAS 

Google Scholar 
Miller, M. S., Ferrato, M.-A., Niec, A., Biesinger, M. C. & Carmichael, T. B. Ultrasmooth gold surfaces prepared by chemical mechanical polishing for applications in nanoscience. Langmuir 30, 14171–14178 (2014).Article 
CAS 
PubMed 

Google Scholar 
Groesbeck, E. C. Metallographic Etching Reagents. Part III. For Alloy Steels (US Department of Commerce, Bureau of Standards, 1925).Chen, W. D., Kang, S.-K., Stark, W. J., Rogers, J. A. & Grass, R. N. The light triggered dissolution of gold wires using potassium ferrocyanide solutions enables cumulative illumination sensing. Sens. Actuat. B 282, 52–59 (2019).Article 
CAS 

Google Scholar 
Haber, F. Nachweis und Fällung der Ferroionen in der Wässerigen Lösung des Ferrocyankaliums. Z. Elektrochem. Angew. Phys. Chem. 11, 846–850 (1905).CAS 

Google Scholar 
Yu, X., Peng, X. & Wang, G. Photo induced dissociation of ferri and ferro cyanide in hydroponic solutions. Int. J. Environ. Sci. Technol. 8, 853–862 (2011).Article 
CAS 

Google Scholar 
Häkkinen, H. The gold–sulfur interface at the nanoscale. Nat. Chem. 4, 443–455 (2012).Article 
PubMed 

Google Scholar 
Abild-Pedersen, F. et al. Scaling properties of adsorption energies for hydrogen-containing molecules on transition-metal surfaces. Phys. Rev. Lett. 99, 016105 (2007).Article 
CAS 
PubMed 

Google Scholar 
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).Article 
CAS 

Google Scholar 
Kresse, G. & Furthmuller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).Article 
CAS 

Google Scholar 
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).Article 
CAS 
PubMed 

Google Scholar 
Grimme, S. Semiempirical GGA‐type density functional constructed with a long‐range dispersion correction. J. Comput. Chem. 27, 1787–1799 (2006).Article 
CAS 
PubMed 

Google Scholar 
Monkhorst, H. J. & Pack, J. D. Special points for Brillouin-zone integrations. Phys. Rev. B 13, 5188 (1976).Article 

Google Scholar 
Köhler, L. & Kresse, G. Density functional study of CO on Rh(111). Phys. Rev. B 70, 165405 (2004).Article 

Google Scholar 
Lizzit, S. et al. Surface core-level shifts of clean and oxygen-covered Ru (0001). Phys. Rev. B 63, 205419 (2001).Article 

Google Scholar 
Tal, A. A., Olovsson, W. & Abrikosov, I. A. Origin of the core-level binding energy shifts in Au nanoclusters. Phys. Rev. B 95, 245402 (2017).Article 

Google Scholar 
Kashiwaya, S. et al. Goldene—exfoliated single-atom-thick sheets of gold. figshare (2024).