▎ 摘　　要

Reliable detection of high-concentration hydrogen (H2) leakage in sharp-vibration environments is highly desired such as in the application of space rockets. As hydrogen has to be detected simultaneously in a wide concentration range and at high concentrations (e.g., 100 v/v%) with outstanding linearity in response/concentration, lightweight features, and excellent tolerance against saturation and vibration, it remains challenging. Here, a flexible and high-concentration H2 sensing has been developed through "dipping-drying " a three-dimensional (3D) porous polyurethane (PU) foam integrated with graphene oxide (GO-PU). Multilayered honeycomb-structured graphene oxide appears to be tightly adhered to faveolate PU. Benefiting from the numerous adsorption sites of the "dual honeycomb " structure and abundant surface functional groups of GO, the GO-PU foam exhibits distinguished response and linearity toward 2-100 v/v% H2 and shows excellent lightweight, tailorability, and flexibility. Remarkably, the foam possesses outstanding sensing stability against 0-180 & DEG; bending and low 0-20% straining, along with outstanding H2 sensing performance even after being pressed by a weight of 200 g, immersed in water, and frozen in a refrigerator at -10.8 & DEG;C. Practically, the GO-PU foam has potential for high-concentration H2 leakage detection, and our synthetic strategy may provide a way to avoid adsorbing saturation in other flexible gas sensing.