Suitable molding and granulation methods are crucial, and an outstanding sphere structure can play a better role in the future scale-up industrial application of K₂CO₃-based CO₂ adsorbent. Water will form a large contact angle on the surface of hydrophobic solution and become sphericity water. In this work, hydrophobic powders (polyethylene (PE), TiO₂, and SiO₂) were selected in the hydrophobic interface-assisted method. The CO₂ adsorption capacity of TiO₂ pellets is 0.50 mmol/g, while that of PE pellets is 0.24 mmol/g, and finally that of SiO₂ pellets is 0.36 mmol/g. Then, experiment proved that high temperature (>500 ℃) makes the hydrophobic powders (i.e, TiO₂ and SiO₂) lose hydrophobicity which make water molecules diffuse faster, while PE is completely decomposed at high temperature. Compared with the pellets calcined at 300 ℃, the TiO2 pellets calcinated at 500 ℃ have an adsorption capacity of 0.70 mmol/g, which is over 1.72 times that of the original pellets, and the other two hydrophobic surfaces are also improved to some extent. Additionally, the appropriate ratio of low-temperature pore forming agent (i.e., urea) can help improve the adsorption performance, while excessive addition will lead to poor CO₂ adsorption performance. In addition, the K₂CO₃/Al₂O₃ pellets also exhibited desirable mechanical properties, with an optimal compressive strength of 41 Mpa. Therefore, the loss of hydrophobicity leads to more active diffusion of water molecules, which may provide a new idea for the future development of CO₂ adsorbents and other areas.