We address the composition-controlled synthesis of monodispersed AgPd alloy nanoparticles (NPs), their assembly for the first time on mesoporous graphitic carbon nitride (mpg-C₃N₄), and the unprecedented catalysis of mpg-C₃N₄@AgPd in the hydrolytic dehydrogenation of ammonia borane (AB) at room temperature. Monodispersed AgPd alloy NPs were synthesized using a high-temperature organic-phase surfactant-assisted protocol comprising the co-reduction of silver(Ⅰ) acetate and palladium(Ⅱ) acetylacetonate in the presence of oleylamine, oleic acid, and 1-octadecene. This protocol allowed the synthesis of four different compositions of AgPd alloy NPs. The AgPd alloy NPs were then assembled on mpg-C₃N₄, reduced graphene oxide, and Ketjenblack using a liquid-phase self-assembly method. Among the three supports tested, the mpg-C₃N₄@AgPd catalysts provided the best activity because of the Mott–Schottky effect, which was driven by the favorable work function difference between mpg-C₃N₄ and the metal NPs. Moreover, the activity of the mpg-C₃N₄@AgPd catalyst was further enhanced by an acetic acid treatment (AAt), and a record initial turnover frequency of 94.1 mol_(hydrogen)·mol_(catalyst)⁻¹·min⁻¹ was obtained. Furthermore, the mpg-C₃N₄@Ag₄₂Pd₅₈-AAt catalyst also showed moderate durability for the hydrolysis of AB. This study also includes a wealth of kinetic data for the mpg-C₃N₄@AgPd-catalyzed hydrolysis of AB.

Monodisperse Ni/Pd core/shell nanoparticles (NPs) have been synthesized by sequential reduction of nickel(Ⅱ) acetate and palladium(Ⅱ) bromide in oleylamine (OAm) and trioctylphosphine (TOP). The Ni/Pd NPs have a narrow size distribution with a mean particle size of 10 nm and a standard deviation of 5% with respect to the particle diameter. Mechanistic studies showed that the presence of TOP was essential to control the reductive decomposition of Ni–TOP and Pd–TOP, and the formation of Ni/Pd core/shell NPs. Using the current synthetic protocol, the composition of the Ni/Pd within the core/shell structure can be readily tuned by simply controlling the initial molar ratio of the Ni and Pd salts. The as-synthesized Ni/Pd core/shell NPs were supported on graphene (G) and used as catalyst in Suzuki–Miyaura cross-coupling reactions. Among three different kinds of Ni/Pd NPs tested, the Ni/Pd (Ni/Pd = 3/2) NPs were found to be the most active catalyst for the Suzuki–Miyaura cross-coupling of arylboronic acids with aryl iodides, bromides and even chlorides in a dimethylformamide/water mixture by using K₂CO₃ as a base at 110 ℃. The G–Ni/Pd was also stable and reusable, providing 98% conversion after the 5^th catalytic run without showing any noticeable Ni/Pd composition change. The G–Ni/Pd structure reported in this paper combines both the efficiency of a homogeneous catalyst and the durability of a heterogeneous catalyst, and is promising catalyst candidate for various Pd-based catalytic applications.