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Integrating multi‐step reactions through tandem catalysis offers potential for efficient chemical engineering processes, but designing an efficient tandem catalyst is challenging. Herein, we report tailoring the d‐band centers of Ni through alloying with a second metal (M = Fe/Co/Cu/Ga), which enables it to be multifunctional site for tandem reductive amination. A linear correlation of d‐band center with yield of primary amine product was observed. Density functional theory and experiments revealed the upshifted d‐band center strengthened the adsorption of Schiff base intermediate in advantageous di(C&N) mode, also narrowed the adsorption energy gap between NH3 and H2. Furthermore, the multifunctional nanoparticles provide a confined space with short diffusion pathway for NH3* and H* to timely react with Schiff base. As a result, the NiFe/AlOx with a d‐band center nearest to the Fermi level exhibited the highest primary amine yield of 96.2% with five consecutive reusability under extremely low H2 pressure, which is superior to other reported precious‐metal‐based catalysts. [ABSTRACT FROM AUTHOR]

Reductive amination of biomass aldehydes is a vital process to synthesize chemical intermediates primary amine, but the selectivity is severely compromised by the self‐condensation of highly reactive imine intermediates. Herein, we proposed a solution by manipulating the adsorption configuration of secondary imine via defect engineering. Specifically, a gradient reduction strategy was used to adjust the driving force of NiCo alloy crystallization, thus motivating the formation of metal vacancy clusters. The primary amine selectivity was raised from 70.9% to 95.1% with defect concentration increased from 36.1% to 42.5% on catalysts. In situ fourier transform infrared spectroscopy (FTIR) and density functional theory demonstrated metal vacancy clusters induced remarkable NiCo electron transfer, which strengthened electronic coupling between secondary imine with catalyst, resulting in a flat configuration that was conducive to CN bond breakage to guarantee smooth conversion into primary amines. This catalyst exhibited potential real‐life application prospects for its low cost, universality in reductive amination of various aldehydes, and long‐life reusability. [ABSTRACT FROM AUTHOR]