Hao Chang,Rui Guo,Ziqiao Sun,Hongzhang Wang,Yi Hou,Qian Wang,Wei Rao,Jing Liu
Liquid metals such as gallium and its alloys can be printed on various substrates to form electronic circuits. However, up to now there are still few methods for the direct writing of liquid metals on common printed paper. Here, a novel conductive material prepared by adding metal powder to a gallium alloy is introduced. The proposed material exhibits low liquidity, excellent plasticity, significantly enhanced adhesivity to paper substrates, which guarantee the stable and flexible electrical connection. The oxide film wrapping the nickel powder forms a skeleton for additional oxidation products, resulting in superior adhesion to paper. In addition, several paper flexible electronic applications are showcased to demonstrate the practical value and reparability of this material. This work paves the way for the design of a facile method of preparing paper electronics.
This study introduces a radial-hierarchical, diffusion-enhanced spatiotemporal sensing paradigm for volatile organic compound (VOC) analysis via an integrated microchamber paper-based chromatomimetic e-nose. The proposed system synergizes interlayer spatiotemporal dynamics with planar spatial variance by employing a radially symmetric electrode array and a hierarchical porous chemoresistive ink (CuP@G). This design leverages molecular diffusion gradients across the sensing plane, enabling precise discrimination of complex VOC mixtures through multidimensional “spatiotemporal fingerprints”. A physics-informed framework integrates molecular transport principles with multitask learning convolutional neural network (MTL-CNN) analytics, achieving unprecedented resolution in real-sample classification. Systematic validation demonstrates superior performance in discriminating diverse VOCs, binary mixtures, and authentic tobacco samples (origin and level classification accuracy: 92–99%). This work establishes a scalable blueprint for high-fidelity VOC analytics, bridging gas diffusion physics with intelligent signal processing to advance e-nose technology toward precision-driven design.