The development of efficient zeolite-based adsorbents with high water uptake capacity is an essential requirement for water adsorption and moisture removal technologies. In the present study, zeolite-Y samples with interconnected hierarchical micro-mesoporous network were synthesized by employing a bifunctional cationic polymer (namely, polydiallydimethyl-ammonium chloride, PDDA), and ion-exchanged with several metal salts (such as Zn, Mg, Li) targeting high capacity water adsorption. We systematically investigated water adsorption behavior of hierarchically porous NaY (HP–NaY) samples and studied the influence of their distinct metal exchange analogues on water affinity and total adsorption capacity. The water affinity and water uptake increased for the HP-NaY samples compared to conventional NaY. HP-NaY samples demonstrating a high water adsorption capacity (17.32–17.98 mmol/g) at 303 K and 0.7 relative pressure (P/Po) when compared to commercial zeolite-Y (CBV-400, 14.83 mmol/g). A further improvement in water uptake was attained by introduction of distinct metal ions into the hierarchical porous zeolite-Y. HP-LiY exhibited the highest water adsorption capacity (19.08 mmol/g at 0.7 P/Po) amounting to 28% and 15% improvement when compared to CBV-400 and CBV-Li respectively. The observed improvements in water adsorption capacity are attributed to (i) the existence of interconnected micro-mesoporous channel network and higher total pore volume and (ii) the enhancement in accessibility of adsorption sites by H₂O molecules. The adsorption data of the samples were also fitted using various adsorption models. Hierarchically porous zeolites displayed site heterogeneity, the latter being rendered by the existence of varying chemical environments between sites within the micropores and the mesopores and the nature of the host metals.

开发具有高吸水能力的高效沸石基吸附剂是吸水除湿技术的基本要求。在本研究中，通过采用双功能阳离子聚合物（即聚二甲基氯化铵，PDDA），并与几种金属盐（如 Zn、Mg、 Li) 以高容量水吸附为目标。我们系统地研究了分层多孔 NaY (HP-NaY) 样品的吸水行为，并研究了它们不同的金属交换类似物对水亲和力和总吸附容量的影响。与传统 NaY 相比，HP-NaY 样品的水亲和力和吸水量增加。与商业沸石-Y（CBV-400，14.83 mmol/g）相比，HP-NaY 样品在 303 K 和 0.7 相对压力 (P/Po) 下表现出高吸水能力 (17.32–17.98 mmol/g)。通过将不同的金属离子引入分级多孔沸石-Y，进一步提高了吸水率。与 CBV-400 和 CBV-Li 相比，HP-LiY 表现出最高的吸水能力（19.08 mmol/g，0.7 P/Po），分别提高了 28% 和 15%。观察到的水吸附能力的提高归因于（i）互连微介孔通道网络的存在和更高的总孔体积以及（ii）H 对吸附位点的可及性的增强 83 毫摩尔/克）。通过将不同的金属离子引入分级多孔沸石-Y，进一步提高了吸水率。与 CBV-400 和 CBV-Li 相比，HP-LiY 表现出最高的吸水能力（19.08 mmol/g，0.7 P/Po），分别提高了 28% 和 15%。观察到的水吸附能力的提高归因于（i）互连微介孔通道网络的存在和更高的总孔体积以及（ii）H 对吸附位点的可及性的增强 83 毫摩尔/克）。通过将不同的金属离子引入分级多孔沸石-Y，进一步提高了吸水率。与 CBV-400 和 CBV-Li 相比，HP-LiY 表现出最高的吸水能力（19.08 mmol/g，0.7 P/Po），分别提高了 28% 和 15%。观察到的水吸附能力的提高归因于（i）互连微介孔通道网络的存在和更高的总孔体积以及（ii）H 对吸附位点的可及性的增强₂ O 分子。还使用各种吸附模型拟合了样品的吸附数据。分级多孔沸石表现出位点异质性，后者是由于微孔和中孔内位点之间存在不同的化学环境以及宿主金属的性质而造成的。