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Dual-atom site catalysts (DACs) have emerged as an ew frontier in heterogeneous catalysis because the synergistic effect between adjacent metal atoms can promote their catalytic activity while maintaining the advantages of singleatom site catalysts (SACs), like 100 %a tomic utilization efficiency and excellent selectivity.H erein, as upported Pd 2 DACw as synthesized and used for electrochemical CO 2 reduction reaction (CO 2 RR) for the first time.The as-obtained Pd 2 DACe xhibited superior CO 2 RR catalytic performance with 98.2 %C Of aradic efficiency at À0.85 Vv s. RHE, far exceeding that of Pd 1 SAC, and coupled with long-term stability.T he density functional theory (DFT) calculations revealed that the intrinsic reason for the superior activity of Pd 2 DACt owardC O 2 RR was the electron transfer between Pd atoms at the dimeric Pd sites.T hus,P d 2 DACp ossessed moderate adsorption strength of CO*, which was beneficial for CO production in CO 2 RR.

The electrochemical splitting of water into hydrogen and oxygen is considered one of the most promising approaches to generate clean and sustainable energy. However, the low efficiency of the oxygen evolution reaction (OER) acts as a bottleneck in the water splitting process. Herein, interface engineering heterojunctions between ZIF‐67 and layered double hydroxide (LDH) are designed to enhance the catalytic activity of the OER and the stability of Co‐LDH. The interface is built by the oxygen (O) of Co‐LDH and nitrogen (N) of the 2‐methylimidazole ligand in ZIF‐67, which modulates the local electronic structure of the catalytic active site. Density functional theory calculations demonstrate that the interfacial interaction can enhance the strength of the CoOout bond in Co‐LDH, which makes it easier to break the H‐Oout bond and results in a lower free energy change in the potential‐determining step at the heterointerface in the OER process. Therefore, the Co‐LDH@ZIF‐67 exhibits superior OER activity with a low overpotential of 187 mV at a current density of 10 mA cm−2 and long‐term electrochemical stability for more than 50 h. This finding provides a design direction for improving the catalytic activity of OER.

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Exploring thermally robust single atom catalysts (SACs) is of great significance. Here, we develop a universal strategy for stabilizing Pt atoms on the mono-oxygen vacancies of CeO2 with diverse exposed facets. The sta-bilization mechanism was proposed that the formed Pt-O-Ce interface will be taken into distortion spontaneously to keep thermodynamics stable through strong metal-support interactions. The highest degree of Pt-O-Ce dis-tortion is achieved over Pt1-CeO2{100} material, which exhibits exceptional efficiency and thermal stability for oxygenated hydrocarbon removal. The enhanced adsorption capacity of O2 and methanol confirmed in the distortion interface is seen as another crucial reason for improving the stability of SACs. Methanol oxidation on Pt1-CeO2{100} obeys the L-H mechanism under relatively low temperature and then goes through to the MVK mechanism with temperature increasing. We believe that these results would bring new opportunities in the fabrication of SACs and applications of them in thermal reactions.

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A series of Cu–SAPO-18 catalysts with various Cu loadings were prepared and their catalytic activities were tested for the selective catalytic reduction of NO with NH3. The catalysts were characterized by means of XRD, N2 adsorption–desorption, TEM, XPS, UV–vis DRS, H2-TPR, NH3-TPD and EPR. Isolated Cu2+ ions are confirmed to be the catalytic active sites. Cu-4.42 catalyst exhibits high NO conversion (>80%) at the lowest temperature of 200 °C among all catalysts. It can be attributed to the maximum amount of isolated Cu2+ ions in Cu-4.42 catalyst. DFT calculations show that the isolated Cu ions are located in the pear shaped cavity and exhibit a preference for the neighboring of 6R planes of Cu–SAPO-18. NH3–SCR mechanism over Cu–SAPO-18 catalyst is elucidated by a combination of in situ DRIFTS technique and DFT calculations, in which the dissociation of NH3 and the oxidation of NO are shown to be key steps in the reaction.