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Asymmetric coordination has emerged as a promising approach to enhance the oxygen evolution reaction (OER) activity, yet achieving a controlled synthesis of asymmetric structures to comprehensively understand the structure‐activity relationship remains challenging. In this study, a facile and effective symmetry‐breaking strategy is reported for tailoring the asymmetric MO5S1‐type metal–organic frameworks (MOFs) catalyst, establishing the correlation between the sulfur (S)‐mediated electron rearrangement and the adsorption/desorption dynamics of oxygen‐related intermediates in OER. Experimental and theoretical calculations reveal that a well‐designed asymmetric structure can effectively lower the d‐band center, optimizing the adsorption behavior of OH* and significantly decreasing the reaction energy barrier for the rate‐determining step (OH* → O*) with enhanced O–H bond cleavage process. The S‐NiFe‐MOF/CFP catalyst demonstrates a remarkable OER performance in an alkaline electrolyte environment. More importantly, the self‐assembled anion exchange membrane water electrolysis cell showcases a low voltage of 1.84 V to deliver the current density of 1 A cm−2, maintaining long‐term stability for over 100 h. This study unveils a precise asymmetric synthesis strategy employing S, highlighting the critical role of manipulating electron redistribution through asymmetric coordination to promote catalytic activity and develop advanced MOF‐based catalysts. [ABSTRACT FROM AUTHOR]

Amorphous metal‐organic frameworks (MOFs) with aperiodic atomic arrangements, featuring high intrinsic activity and rich active sites, have emerged as promising oxygen evolution reaction (OER) catalysts. However, the quantitative structure‐activity relationships (SARs) that determine the OER activity, the key to a rational catalyst design, remain unresolved. Inspired by controllable amorphization engineering, the amorphous MOF structures are rationally constructed as an ideal platform to explore the SAR in catalyzing OER. The mechanistic studies show that the OER activity could be volcano‐shape correlated with either constant adsorption energy difference between OOH* and O* (ΔGOOH* − ΔGO*) or the position of the d band center. The amorphous MOF (Ni8Co2‐BDC), situated close to the volcano summit, possesses an appropriate Ed energy level, which exhibits the balanced intermediates adsorption/desorption ability and consequently results in the boosted catalytic activity and long‐term stability. This work supplies new perspectives to investigate the SAR in amorphous MOF structures, thereby guiding the rational design of advanced OER catalysts. [ABSTRACT FROM AUTHOR]

Deliberate modulation of the electronic structure via interface engineering is one of promising perspectives to build advanced catalysts for urea oxidation reaction (UOR) at high current densities. However, it still remains some challenges originating from the intrinsically sluggish UOR dynamics and the high energy barrier for urea adsorption. In response, we report the coupled NiSe2 nanowrinkles with Ni5P4 nanorods heterogeneous structure onto Ni foam (denoted as NiSe2@Ni5P4/NF) through successive phosphorization and selenization strategy, in which the produced closely contacted interface could provide high-flux electron transfer pathways. Theoretical findings decipher that the fast charge transfer takes place at the interfacial region from Ni5P4 to NiSe2, which is conducive to optimizing adsorption energy of urea molecules. As expected, the well-designed NiSe2@Ni5P4/NF only requires the low potential of 1.402 V at the current density of 500 mA·cm−2. More importantly, a small Tafel slope of 27.6 mV·dec−1, a high turnover frequency (TOF) value of 1.037 s−1 as well as the prolonged stability of 950 h at the current density of 100 mA·cm−2 are also achieved. This study enriches the understanding on the electronic structure modulation via interface engineering and offers bright prospect to design advanced UOR catalysts. [ABSTRACT FROM AUTHOR]