Tailoring free spaces around catalytic sites and constructing inter-connected channels between them are highly attractive for achieving easy accessibility of reactants to catalytic sites. In this study, a strategy for constructing free space around base sites through molecular imprinting and interconnected channel between them by solvent annealing was developed to achieve high reactant accessibility. The as-fabricated nanobowls with particle sizes of 345 nm were efficient solid bases with fast mass transfer owing to the characteristic architectural features, such as a thin shell thickness (30 nm), free space around the base centered at 4.0 nm, mesoporous channels (5−50 nm), and a hollow interior. The influence of porosity on catalytic behavior was investigated using Knoevenagel condensations, and was found to promote various aromatic aldehydes to afford products at room temperature in 84–98 % yield within 2 h. Furthermore, the catalyst reused ten times was able to be restored to obtain original high catalytic activity.

在催化剂位点附近自由空间并在它们之间构造相互连接的通道对于使反应物易于接近催化剂位点非常有吸引力。在这项研究中，开发了一种通过分子印迹和通过溶剂退火在碱基之间相互连接的通道在碱基周围构建自由空间的策略，以实现较高的反应物可及性。由于具有独特的建筑特征，例如厚度薄的外壳（30 nm），围绕中心的自由空间（中心为4.0 nm），介孔通道（ 5-50 nm），以及一个中空的内部。使用Knoevenagel缩合研究了孔隙度对催化行为的影响，并发现它们可以促进各种芳香醛在室温下在2小时内以84–98％的收率提供产品。此外，能够恢复重复使用十次的催化剂以获得原始的高催化活性。