Traditionally, hydrophobic geopolymer foams (GPFs) are prepared in two steps: GPFs hardening and hydrophobic treatment. Here, we reported a novel two-in-one strategy for the simultaneous foaming and hydrophobization of GPFs by using polymethylhydrosiloxane (PMHS) as the key double-functional agent and calcium stearate (CS) as the foam stabilizer. With the combined effect of PMHS and CS, the pore size could be controlled in the range of 0.27–6.82 mm and bulk density in 200–700 kg/m³, which further influenced the compressive strength and thermal conductivity. The as-prepared GPFs showed superhydrophobic properties, with contact angles as high as 170°. Theoretically, alkylated nano‑silicon fibers grew on the GPFs surface, which acted as a hydrophobic cover and increase the surface roughness, both contributing to the superhydrophobic. Overall, our work presents a novel two-in-one strategy for the preparation of superhydrophobic GPFs, which would be of great significance to the application of GPFs.

传统上，疏水性地质聚合物泡沫 (GPF) 的制备分为两个步骤：GPF 硬化和疏水处理。在这里，我们报道了一种新颖的二合一策略，通过使用聚甲基氢硅氧烷 (PMHS) 作为关键的双功能剂和硬脂酸钙 (CS) 作为泡沫稳定剂来同时发泡和疏水化 GPF。在PMHS和CS的共同作用下，孔径可以控制在0.27-6.82 mm范围内，堆积密度可以控制在200-700 kg/m ³，这进一步影响了抗压强度和导热性。所制备的 GPF 具有超疏水特性，接触角高达 170°。从理论上讲，烷基化纳米硅纤维在 GPF 表面上生长，充当疏水性覆盖层并增加表面粗糙度，两者都有助于超疏水性。总体而言，我们的工作为制备超疏水 GPFs 提出了一种新颖的二合一策略，这对 GPFs 的应用具有重要意义。