Synergetic Lithium and Hydrogen Bonds Endow Liquid-free Photonic Ionic Elastomer with Mechanical Robustness and Electrical/optical Dual-output.

Photonic ionic elastomers (PIEs) capable of multiple signal outputs is intriguing in flexible interactive electronics. However, fabricating PIEs with simultaneous mechanical robustness, good ionic conductivity and brilliant structure color still remains challenging. Here, we break the limitations through introducing synergistic effect of lithium and hydrogen bonds into an elastomer. In virtue of lithium bonding between lithium ions and carbonyl groups in the polymer matrix as well as hydrogen bonding between silanol on the surface of silica nanoparticles (SiNPs) and ether groups along polymer chains, the PIEs demonstrate mechanical strength up to 4.3 MPa and toughness up to 8.6 MJ m -3 . Meanwhile, the synchronous electrical and optical output under mechanical strains could be achieved in the PIEs with the presence of dissociated ions contributed by lithium bond and non-close-packed SiNPs stabilized by hydrogen bond. Moreover, due to their liquid-free nature, the PIEs exhibit extraordinary stability and durability, which could withstand extreme conditions including both high and low temperatures as well as high humidity. This work provides a promising molecular engineering route to construct high performance photonic ionic conductors towards advanced ionotronic applications. This article is protected by copyright. All rights reserved.