Formaldehyde solution ch2o

Copper foil (0.025mm thick, 99.8%) was commercially obtained from Alfa Aesar (Ward Hill, MA, USA). All chemicals were purchased from commercial sources and used without further purification. (3-Aminopropyl)triethoxysilane (APTMS, 95%, Acros, Geel, Belgium), resorcinol (C₆H₆O₂, 99%, Alfa Aesar, USA), ammonium hydroxide (NH₄OH, 28%, Alfa Aesar, USA), formaldehyde solution (CH₂O, 37%, Merck, Darmstadt, Germany), silver nitrate (AgNO₃, 99%, Alfa Aesar, USA), hydrochloric acid (HCl, 37%, Sigma-Aldrich, Darmstadt, Germany), rhodamine 6G (R6G, 99.8%, Acros, Germany), amoxicillin (50 mg/mL, Y F Chemical, New Taipei City, Taiwan), 5-fluorouracil (5FU, 50 mg/mL, Nang Kuang Pharmaceutical, Tainan, Taiwan), and ethanol (C₂H₅OH, 99%, Sigma-Aldrich, Darmstadt, Germany) were used in this experiments. De-ionized water with a resistivity higher than 18.2 MΩ was used for all solution preparations.

A 0.25 mm thick titanium (Ti) foil (99.5%) was commercially sourced from Alfa Aesar (Haverhill, MA, USA). All chemicals used were obtained from commercial suppliers and were employed without the need for further purification. Specifically, hydrochloric acid (HCl, 37%), sodium hydroxide (NaOH, 97%), ethanol (C₂H₅OH, 99%), L-ascorbic acid (C₆H₈O₆, 99%), and rhodamine B (RhB, C₂₈H₃₁ClN₂O₃, 95%) were acquired from Sigma-Aldrich (Steinheim, Germany). (3-Aminopropyl)trimethoxysilane (C₆H₁₇NO₃Si, APTMS, 95%) was acquired from Acros (Renningen, Germany). Resorcinol (C₆H₆O₂, 99%), ammonium hydroxide (NH₄OH, 28%), methylene blue (MB, C₁₆H₁₈ClN₃S, 95%), and silver nitrate (AgNO₃, 99%) were obtained from Alfa Aesar (USA). A formaldehyde solution (CH₂O, 37%) was acquired from Merck (Darmstadt, Germany). De-ionized water with a resistivity exceeding 18.2 MΩ was used to prepare all solutions.