Li Weerapat, Anantachaisophon Supphanat, Vachiraanun Thanakrit, Promchaisri Worachon, Sangsawang Pongpop, Tanalikhit Pattarapon, Ittisanronnachai Somlak, Atithep Thassanant, Sanguanchua Passapan, Ratanasangsathien Arjaree, Jirapunyawong Mathus, Suntiworapong Siriporn, Warintaraporn Sakol, Mueanngern Yutichai
Department of Chemistry, Kamnoetvidya Science Academy, 999 Moo 1, Pa Yup Nai, Wang Chan, Rayong 21210, Thailand.
Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea.
ACS Omega. 2023 Sep 14;8(38):34919-34927. doi: 10.1021/acsomega.3c04303. eCollection 2023 Sep 26.
Deposition of CuNPs on silver film gives rise to the formation of active Ag-Cu interfaces leading to dramatic enhancements in antibacterial activity against . Transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDAX) analyses reveal that CuNPs are covered in a thin CuO shell, while X-ray photoelectron spectroscopy measurements (XPS) reveal that the Ag film samples contain significant amounts of AgO. XPS analyses show that the deposition of CuNPs on Ag films leads to the formation of a photoactive AgO-CuO heterostructure. Following a -scheme mechanism, electrons from the conduction band of AgO recombine with photogenerated holes from the valence band of CuO. Consequently, electrons at CuO's conduction band render Cu reduced and cause reductive activation of surface oxygen species on Cu forming reactive oxygen species (ROS). Interaction between metallic Cu and ROS species leads to the formation of a Cu(OH) phase. Both ROS and Cu(OH) species have previously been reported to lead to enhanced antibacterial properties. Holes on AgO produce a highly oxidized AgO phase, a phase reported to exhibit excellent antibacterial properties. Quantitative analysis of Cu and Ag high-resolution X-ray photoelectron spectroscopy (HR-XPS) spectra directly reveals several-fold increases in these active phases in full agreement with the observed increase in antibacterial activities. This study provides insight and surface design parameters by elucidating the important roles of Ag and Cu's bifunctionality as active antibacterial materials.
铜纳米颗粒沉积在银膜上会导致活性银 - 铜界面的形成，从而显著增强对……的抗菌活性。透射电子显微镜（TEM）和能量色散X射线光谱（EDAX）分析表明，铜纳米颗粒被一层薄的氧化铜壳覆盖，而X射线光电子能谱测量（XPS）表明银膜样品中含有大量的氧化银。XPS分析表明，铜纳米颗粒在银膜上的沉积导致形成光活性氧化银 - 氧化铜异质结构。按照 - 方案机制，来自氧化银导带的电子与来自氧化铜价带的光生空穴复合。因此，氧化铜导带上的电子使铜还原，并导致铜表面的氧物种发生还原活化，形成活性氧（ROS）。金属铜与ROS物种之间的相互作用导致形成氢氧化铜相。先前已有报道称ROS和氢氧化铜物种都会导致抗菌性能增强。氧化银上的空穴产生高度氧化的氧化银相，据报道该相具有优异的抗菌性能。对铜和银的高分辨率X射线光电子能谱（HR - XPS）光谱进行定量分析，直接揭示了这些活性相增加了几倍，这与观察到的抗菌活性增加完全一致。本研究通过阐明银和铜作为活性抗菌材料的双功能性的重要作用，提供了见解和表面设计参数。
