Na'es Maram, Lühl Lars, Kanngießer Birgit
Institute for Optics and Atomic Physics, Technical University Berlin Hardenbergstr. 36 10623 Berlin Germany
Nanoscale Adv. 2024 Dec 11;7(4):1061-1076. doi: 10.1039/d4na00877d. eCollection 2025 Feb 11.
Gilded wall paintings such as those in Petra-Jordan undergo deterioration processes such as delamination and loss of the gold layer. The aim of this work is to produce a functioning long-lasting adhesive that compensates for binder and gold loss while stabilising the gold layer. Polymer-stabilised gold nanoparticles (AuNPs) as a conservation material for gilded heritage paintings (Nano Gold Gel (NGG)) were synthesised using two facile and affordable synthesis approaches. AuNPs enhance the stability of the adhesive polymer over time and introduce mass conservation to the gold layer. Two natural polymers and one synthetic polymer, frequently used in conservation as adhesives, were used as reducing agents and stabilisers for the nanoparticles. The chemical alteration of the polymers and the Au-polymer interaction at the molecular level were investigated with FTIR spectroscopy, while the chemical environment of gold was investigated with X-ray absorption spectroscopy (XANES/EXAFS). The synthesized NGG was applied on the replica samples to reattach the gold layer to its support. Characterisation results indicate that the formation of AuNPs stabilised by the three polymers did not alter the chemical structure of the polymers. The applied NGG successfully achieved re-adhesion and exhibited appropriate optical and chemical properties for use as a conservation material.
诸如约旦佩特拉的那些镀金壁画会经历分层和金层脱落等劣化过程。这项工作的目的是制备一种能发挥作用且持久的粘合剂，在稳定金层的同时弥补粘合剂和金的损失。采用两种简便且经济的合成方法合成了聚合物稳定的金纳米颗粒（AuNP）作为镀金遗产壁画的保护材料（纳米金凝胶（NGG））。随着时间的推移，AuNP增强了粘合剂聚合物的稳定性，并为金层引入了质量守恒。三种常用于保护领域作为粘合剂的天然聚合物和一种合成聚合物被用作纳米颗粒的还原剂和稳定剂。用傅里叶变换红外光谱（FTIR）研究了聚合物的化学变化以及分子水平上的金 - 聚合物相互作用，同时用X射线吸收光谱（XANES/EXAFS）研究了金的化学环境。将合成的NGG应用于复制样品，以使金层重新附着于其支撑物上。表征结果表明，由这三种聚合物稳定的AuNP的形成并未改变聚合物的化学结构。所应用的NGG成功实现了重新粘附，并表现出适合用作保护材料的光学和化学性质。
