The fabrication of small Pd nanoparticles (NPs) anchored on titanium dioxide (TiO) supports remains a great challenge due to its high surface energy. Herein, flower-like three dimensional (3D) TiO microstructures assembled from needle flakes are fabricated thru a facile evaporation-induced assisted hydrothermal method, and then modified with amines group (3D-TiO-NH). Small and uniform dispersed Pd nanoparticles were anchored on the surface of 3D-TiO-NH supports using polyol reduction method. Remarkably, the obtained 3D-TiO-NH supported Pd-based catalyst (Pd@3D-TiO-NH) demonstrated an optimal 4-NP catalytic hydrogenation efficiency ( = 1.09 min), which is 1.56 and 3.52 times superior than that of the Pd@3D-TiO ( = 0.699 min) and Pd@TiO–P25 ( = 0.31 min) catalysts, respectively. In-depth investigation of the structure-property relationship by SEM, XRD, N adsorption-desorption isotherm, TEM, XPS, CO chemisorption and CO-FTIR reveal that the optimal catalytic hydrogenation activity of Pd@3D-TiO-NH can be credited to its 3D hierarchical structure (interconnected needle flakes) and the amines group existing on the surface of flower-like three dimensional hierarchical TiO, which control the Pd particles size (2.7 nm) and uniform dispersion (43.5%) to generate more surface active Pd entities over Pd@3D-TiO-NH.

中文翻译：

---

Pd 纳米颗粒锚定在胺接枝 3D TiO2 催化剂上，用于改进 4-硝基苯酚的选择性加氢

由于其高表面能，锚定在二氧化钛 (TiO) 载体上的小型钯纳米粒子 (NP) 的制造仍然是一个巨大的挑战。在此，通过简单的蒸发诱导辅助水热方法制备了由针状薄片组装而成的花状三维（3D）TiO 微结构，然后用胺基（3D-TiO-NH）进行修饰。使用多元醇还原法将小而均匀分散的 Pd 纳米颗粒锚定在 3D-TiO-NH 载体的表面。值得注意的是，所获得的3D-TiO-NH负载的Pd基催化剂（Pd@3D-TiO-NH）表现出最佳的4-NP催化加氢效率（= 1.09 min），比Pd的催化加氢效率高1.56和3.52倍。分别为@3D-TiO ( = 0.699 min) 和 Pd@TiO–P25 ( = 0.31 min) 催化剂。通过SEM、XRD、N吸附-脱附等温线、TEM、XPS、CO化学吸附和CO-FTIR对结构-性能关系的深入研究表明，Pd@3D-TiO-NH的最佳催化加氢活性可归因于其3D分层结构（相互连接的针状薄片）和花状三维分层TiO表面存在的胺基团，控制Pd颗粒尺寸（2.7 nm）和均匀分散（43.5％）以生成更多表面活性Pd实体Pd@3D-TiO-NH。