The development of efficient non-precious metal catalysts (NPMCs) can help reduce the cost of fuel cells and accelerate their commercialization.
　　At present, non-precious metal catalysts suffer from poor stability in proton exchange membrane fuel cells, and their degradation mechanism at the molecular scale is unclear.
　　Recently, a research group led by Prof. SUN Gongquan Sun and Prof. WANG Suli collaborated with Prof. WANG Junhu's group from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) revealed the degradation mechanism of Fe-N-C-type NPMCs.
　　This work was published in Applied Catalysis B: Environmental on March 4.
　　The influence of structure and structural evolution of active site on the demetallation of Fe-N-C is investigated by the end-of-test/in-situ M？ssbauer spectroscopy and ab initio molecular dynamics simulation (Image by XU Xinlong)
　　The researchers found that D1 was the main active site for oxygen reduction reaction and the demetallation was responsible for the degradation of Fe-N-C. The degradation was initially rapid but slow afterward, which could be explained by the different activity and stability of various FeN4 sites.
　　Moreover, they revealed that the adsorption of oxygenated intermediate and the motivation of electric field could further weaken the Fe-N bond in FeN4, leading to more severe demetallation. The faster degradation of Fe-N-C under higher potential was due to the stronger adsorption and field intensity.
　　This work provides insight into the degradation mechanism of Fe-N-C at the molecular level. It can work as the guidance for the future development of stable NPMCs in fuel cell devices.
　　This work was supported by the National Natural Science Foundation of China, and the Postdoctoral Science Foundation of China. (Text by XU Xinlong)

　　Methane, the main constituent in shale gas and flammable ice, is expected to replace petroleum to produce high value-added chemicals such as aromatics. Methane is relatively highly inert, which is caused by the high C-H bond strength and supersymmetric structure and hinders its applications.
　　Recently, a research team led by Prof. LIU Zhongmin and Prof. ZHU Wenliang from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) developed a strategy for the transformation of methane into aromatics by coupling of CH3Cl with CO over H-zeolites.
　　This study was published in Angew. Chem. Int. Ed. on Feb. 1. It was selected as Very Important Paper and inside back cover.
　　Highly Enhanced Aromatics Selectivity by Coupling of Chloromethane and Carbon Monoxide over H-ZSM-5 (Image by FANG Xudong)
　　The researchers used H-ZSM-5 as catalysts to achieve high aromatics selectivity as well as high selectivity of benzene, toluene, and xylene (BTX).
　　They found that the selectivity to aromatics increased from 39.0% to 79.3% after introducing CO, and corresponding BTX selectivity increased from 17.7% to 48.0% at 2.0 MPa, 673 K. After optimizing reaction conditions, the aromatics selectivity reached as high as 82.2%, and BTX selectivity as high as 59.3%.
　　Moreover, they discovered that 2,3-dimethyl-2-cyclopentene-1-one (DMCPO) was generated from acetyl groups and olefins. And CO was proven to be inserted into the DMCPO and aromatics rings.
　　Then they proposed a new aromatization mechanism, including the formation of the above intermediates, which conspicuously weakened the hydrogen transfer reaction, resulting in an increase in aromatics selectivity and a drop in alkanes.
　　"Our study broadens approaches towards the transformation of methane into chemicals, and ensure the sustainable development of natural gas in an environmental pathway," said Prof. ZHU.
　　The study was supported by the National Natural Science Foundation of China, the Strategic Priority Research Program of CAS, the Dalian High-Level Talent Innovation Support Program, and National Special Support Program for High-Level Talents. (Text by FANG Xudong and LIU Hongchao)

　　A research team led by Prof. CHEN Ping and Associate Prof. LIU Lin from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Associate Prof. WU Anan from Xiamen University, discovered that samarium hydride (Sm-H) species, in situ generated on the surface of Ru clusters/Sm2O3 catalyst under reaction conditions, could work synergistically to enhance the catalytic activity of Ru clusters for ammonia synthesis.
　　This study was published in ACS catalysison Jan. 28.
　　Schematic illustrations of the synergistic effect of surface hydride species and Ru clusters for catalytic ammonia synthesis reaction (Image by ZHANG Xilun)
　　The researchers synthesized sub-nanometer Ru clusters on Sm2O3 (Ru clusters/Sm2O3) and investigated its catalytic performance for ammonia synthesis. "Under mild reaction conditions, this catalyst showed good activity as well as high stability, thermal stability, and water-tolerant stability," said Prof. CHEN.
　　Furthermore, experimental and theoretical results revealed that Sm2O3 featuring surface Sm-H species could regulate the electronic structure of Ru clusters, making the catalyst active for hydrogen and nitrogen activation. And the Sm-H species on the Ru/Sm2O3 catalyst could directly participate in the formation of ammonia, rendering the catalyst exceptionally active in ammonia synthesis.
　　"The discovery of the synergy role of surface hydride species can deepen the molecular-level understanding of active sites and reaction mechanism of Ru-based catalysts during the ammonia synthesis process," said Prof. CHEN, "and it also provides an opportunity for the rational design of efficient Ru-based ammonia synthesis catalysts under mild conditions."
　　This work was supported by the National Natural Science Foundation of China, Dalian National Laboratory for Clean Energy, and K. C. Wong Education Foundation. (Text by ZHANG Xilun and LIU Lin)

　　Organophosphorus pesticides (OPs), a class of lethalnerve agents widely used in agriculture, pose an extreme threat to human health and environment.
　　Electrochemical biosensor based on the inhibition of acetylcholinesterase (AChE) has been regarded as an ideal tool for rapid detection of OPs, but it is suffered from the sluggish electrode kinetics and high oxidation potential toward signal species.
　　Recently, a research group led by Prof. LU Xianbo and Prof. CHEN Jiping from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) has developed a high-performance electrochemical biosensor for the interference-free detection of OPs.
　　This study was published in Biosensors and Bioelectronics on Feb. 21.
　　Schematic illustrations of the biosensor fabrication and OPs detection (Image by NIU Kai)
　　The researchers synthesized a nanocomposite of ultrafine Cu quantum dots (QD) uniformly loaded on three-dimensional ultrathin graphdiyne (GDY) nanosheets (denoted as Cu@GDY) via a one-step strategy. Cu@GDY showed a high density of active sites with persistent stability.
　　Then, they fabricated an AChE biosensor based on Cu@GDY to detect OPs and found that the results of the Cu@GDY nanocomposite could amplify the electrochemical signal and reduce the oxidation potential for OPs.
　　Moreover, they investigated the potential electro-catalysis mechanism and structure-activity relationships of the proposed biosensor through characterizing the kinetics of electrode reaction, the source of active sites, and the interaction between signal species and active site. "After theoretical derivation and experimental verification of enzyme inhibition kinetics, the biosensor was verified to have high sensitivity to detect OPs," said Prof. LU.
　　This work was supported by the National Natural Science Foundation of China, and the Dalian Science and Technology Innovation Fund. (Text by NIU Kai)

　　Pt-based electrocatalysts are promising for sluggish oxygen reduction reaction (ORR) in Polymer electrolyte membrane fuel cells (PEMFCs). However, the high cost and poor durability of Pt-based electrocatalysts hinder the commercialization of PEMFC.
　　Recently, a research group led by Prof. SUN Gongquan and Prof. WANG Suli from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) fabricated a core-shell structure platinum-rhodium alloy (PtRh/Pt) electrocatalyst for oxygen reduction reaction with ultra-high stability and revealed its synergistic stabilization mechanism.
　　This study was published in ACS catalysis on Feb. 25.
　　Schematic illustrations of the structure of the end of PtRh NDs during the 10K accelerated durability test cycles (Image by AN Zhao)
　　The researchers fabricated dendrite-like PtRh alloy catalyst by one-pot synthetic method, which underwent a dramatically structural evolution during the accelerated durability test. They found that the PtRh alloy catalyst could form a Pt-rich surface during the first 10K accelerated durability test cycles by the "self-healing" effect.
　　Moreover, they found that the segregation energy of rhodium atoms was higher than that of cobalt and nickel in other core-shell structures. Therefore, after 90,000 accelerated durability test cycles, the half-wave potential only shifted negatively by about 5 mV, and the mass activity remained 88%.
　　The stability of this PtRh/Pt catalyst was much higher than that of commercial platinum-carbon catalysts.
　　The study provides new opportunity for the practical design of durable Pt-based oxygen reduction reaction electrocatalysts for the commercialization of PEMFCs. (Text by AN Zhao)

　　Metformin, the most prescribed antidiabetic medicine, has shown other benefits such as anti-ageing and anticancer effects. However, the direct molecular target of metformin remains unknown.
　　Recently, a research group led by Prof. LIN Shengcai and Prof. DENG Xianming from Xiamen University, in collaboration with Prof. PIAO Hailong’s group from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), identified PEN2, a subunit of γ-secretase, as a binding partner of metformin and revealed its mechanism.
　　Their findings were published in Nature on Feb. 23.
　　Schematic diagramme showing that the FBP-unoccupied aldolase-triggered glucose sensing and the PEN2-mediated metformin signalling axes converge at the v-ATPase complex to trigger AMPK activation. (Image by WANG Wen)
　　The researchers synthesized a photoactive metformin probe to identify PEN2. They revealed that metformin could bind PEN2 and initiate a route that intersected, through ATP6AP1, the lysosomal glucose-sensing pathway for AMP-activated protein kinase activation.
　　This study ensured that metformin exerts its therapeutic benefits in patients without substantial adverse effect.
　　This work was supported by the Natural Science Foundation of China. (Text by WANG Wen)