The development of atomically precise dinuclear heterogeneous catalysts is promising to achieve efficient catalytic performance and is also helpful to the atomic-level understanding on the synergy mechanism under reaction conditions. Here, we report a Ni 2 (dppm) 2 Cl 3 dinuclear-cluster-derived strategy to a uniform atomically precise Ni 2 site, consisting of two Ni 1 −N 4 moieties shared with two nitrogen atoms, anchored on a N-doped carbon. By using operando synchrotron X-ray absorption spectroscopy, we identify the dynamically catalytic dinuclear Ni 2 structure under electrochemical CO 2 reduction reaction, revealing an oxygen-bridge adsorption on the Ni 2 −N 6 site to form an O−Ni 2 −N 6 structure with enhanced Ni−Ni interaction. Theoretical simulations demonstrate that the key O−Ni 2 −N 6 structure can significantly lower the energy barrier for CO 2 activation. As a result, the dinuclear Ni 2 catalyst exhibits >94% Faradaic efficiency for efficient carbon monoxide production. This work provides bottom-up target synthesis approaches and evidences the identity of dinuclear sites active toward catalytic reactions.

Elucidating the interaction between different atomic species of the bimetallic nanoparticles under reaction conditions is key to the design of efficient catalysts. Here, we report a laser-assisted strategy towards PtRu...

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Oxygen activation, including oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is at the heart of many important energy conversion processes. However, the activation mechanism of Ba-containing perovskite materials is still ambiguous, because of the complex four-electron transfer process on the gas-solid interfaces. Here, we directly observe that BaO and BaO 2 segregated on Ba-containing material surface participate in the oxygen activation process via the formation and decomposition of BaO 2 . Tens of times of increase in catalytic activities was achieved by introducing barium oxides in the traditional perovskite and inert Au electrodes, indicating that barium oxides are critical for oxygen activation. We find that BaO and BaO 2 are more active than the B-site of perovskite for ORR and OER, respectively, and closely related to the high activity of Ba-containing perovskite.

Exploring high-efficiency catalysts for the electrochemical hydrogen evolution reaction (HER) in alkaline environments is attractive but remains challenging.Here we report a coordination regulation strategy to tune the atomic structure of Ru cluster catalysts supported on Ti 3 C 2 T x MXene (Ru-Ti 3 C 2 T x ) for the HER. We identify that the coordination number (CN) of Ru−Ru could be slightly regulated from 2.1 to 2.8 by adjusting the synthesized temperature so as to achieve an optimal catalytic configuration. The Ru-Ti 3 C 2 T x with a CN Ru−Ru of 2.8 exhibits the best catalytic activity with a low overpotential of 96 mV at 10 mA cm −2 and a mass activity about 11.5 times greater than the commercial Pt/C catalyst. Density functional theory calculations demonstrated that the small Ru clusters have a stronger covalent interaction with Ti 3 C 2 T x support leading to an optimal ΔG H* value. This work opens up a general avenue to modulate the coordination environment of catalysts for the HER.

Surface chemistry modification represents a promising strategy to tailor the adsorption and activation of reaction intermediates for enhancing activity. Herein, we designed a surface oxygen-injection strategy to tune the electronic structure of SnS2 nanosheets, which showed effectively enhanced electrocatalytic activity and selectivity of CO2 reduction to formate and syngas (CO and H2). The oxygen-injection SnS2 nanosheets exhibit a remarkable Faradaic efficiency of 91.6% for carbonaceous products with a current density of 24.1 mA cm−2 at −0.9 V vs RHE, including 83.2% for formate production and 16.5% for syngas with the CO/H2 ratio of 1:1. By operando X-ray absorption spectroscopy, we unravel the in situ surface oxygen doping into the matrix during reaction, thereby optimizing the Sn local electronic states. Operando synchrotron radiation infrared spectroscopy along with theoretical calculations further reveals that the surface oxygen doping facilitated the CO2 activation and enhanced the affinity for HCOO* species. This result demonstrates the potential strategy of surface oxygen injection for the rational design of advanced catalysts for CO2 electroreduction.

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