J Zhang, Qiubo Zhang, Qikun Feng, Xiao Sun, Lin Xu, Zhongxuan Wang, Xueying Zheng, Linlin Yang, Saurabh Khuje, Haimei Zheng, Liangbing Hu, Shenqiang Ren
Copper's exceptional electrical and thermal conductivities make it essential for electronics and energy systems. However, oxidation and corrosion limit its long-term reliability, and existing protection strategies often involve high-temperature or multistep processing. We report a molecularly reactive strategy that converts copper precursors to metallic copper at <150°C, while generating an ultrathin carbonaceous and copper(I) surface passivation. Catechol-based ligands mediate copper reduction, enable low-temperature interparticle fusion, and impart surface passivation, yielding flexible copper with low resistivity and exceptional stability (>1000 hours in acid, >200 hours in sulfide, >240 hours at 140°C). This strategy resolves the long-standing trade-off between conductivity, corrosion resistance, and processability for next-generation flexible electronics and energy systems.