Monolithic, nitrogen-doped carbon sorbents were prepared from resorcinol-urea-formaldehyde resins and physically activated with CO₂ for different activation times. The effect of the activation time on the water sorption behavior and the physicochemical properties were investigated. Longer activation times lead to a steeper slope of the water sorption isotherm and, due to a higher specific surface area and micropore volume, an increased water sorption capacity. It was found that, after physical activation for 3 h at 800 °C, the physically activated, nitrogen-doped carbon has a high surface area (>1000 m²/g) and a high water sorption capacity (50 wt%). In a miniaturized adsorption heat pump test stand, the best candidate material was assessed alongside commercial silica gel for reference. At a temperature swing from 90 °C → 50 °C, the CO₂-activated carbon exhibits a maximal specific cooling power which is a factor of 1.7 higher in comparison with the reference silica gel (429 W/kg versus 255 W/kg). At a more applicable temperature swing, 60 °C → 30 °C, the CO₂-activated carbon yields a specific cooling power 3.8 times higher than that of the silica gel reference (932 W/kg versus 240 W/kg).

由间苯二酚-脲-甲醛树脂制得整体式，氮掺杂的碳吸附剂，并在不同的活化时间下用CO ₂进行了物理活化。研究了活化时间对水吸附行为和理化性质的影响。更长的活化时间导致吸水等温线的斜率更陡，并且由于更高的比表面积和微孔体积而导致了更大的吸水能力。发现在800°C的温度下进行3 h的物理活化后，经物理活化的氮掺杂碳具有较高的表面积（> 1000 m ²/ g）和高吸水率（50wt％）。在小型吸附热泵试验台上，与商用硅胶一起评估了最佳候选材料，以供参考。在90°C→50°C的温度范围内，CO ₂活化的碳表现出最大的比冷却功率，与参考硅胶相比（429 W / kg对255 W / kg），其最大比冷却功率高1.7倍。 。在更合适的温度范围（60°C→30°C）下，CO ₂活化的碳产生的比冷却功率是硅胶参考值的比冷却功率（932 W / kg对240 W / kg）高3.8倍。