Recent Advances in Revealing the Electrocatalytic Mechanism for Hydrogen Energy Conversion System.

In light of the intensifying global energy crisis and the mounting demand for environmental protection, it is of vital importance to develop advanced hydrogen energy conversion systems. Electrolysis cells for hydrogen production and fuel cell devices for hydrogen utilization are indispensable in hydrogen energy conversion. As one of the electrolysis cells, water splitting involves two electrochemical reactions, hydrogen evolution reaction and oxygen evolution reaction. And oxygen reduction reaction coupled with hydrogen oxidation reaction, represent the core electrocatalytic reactions in fuel cell devices. However, the inherent complexity and the lack of a clear understanding of the structure-performance relationship of these electrocatalytic reactions, have posed significant challenges to the advancement of research in this field. In this work, the recent development in revealing the mechanism of electrocatalytic reactions in hydrogen energy conversion systems is reviewed, including in situ characterization and theoretical calculation. First, the working principles and applications of operando measurements in unveiling the reaction mechanism are systematically introduced. Then the application of theoretical calculations in the design of catalysts and the investigation of the reaction mechanism are discussed. Furthermore, the challenges and opportunities are also summarized and discussed for paving the development of hydrogen energy conversion systems.

Preliminary mechanism of inhibitor of SGLT2 in fatty liver cold ischemia injury.

With rapid development of liver transplantation technology, the demand for transplants have reached beyond the supply of organs, and thus development of effective strategies to reduce cold ischemia injury in fatty liver is important. Here, we explored the potential effect of SGLT-2 inhibitor in cold ischemia injury, fatty livers from 2 weeks methionine and choline deficient diet (MCD) rats were administered. After one week of intragastric administration of Sodium-dependent glucose transporters (SGLT-2) inhibitor empagliflozin (EMPA) or NaCI, liver were stored for 24 h. The results showed that EMPA could significantly reduce the cold ischemic injury in the mitochondria of fatty liver. To explore the mechanism, signal transducers and activators of transcription 3(STAT3) inhibitor AG490 group was used in a similar manner. We detected the changes in p-signal transducers and activators of transcription 3 (P-STAT3), alcohol-dehydrogenase 2 (ALDH2) and degree of apoptosis in three distinct groups. The results suggested that the protein expression of P-STAT3 and ALDH2 was higher in the EMPA group than in other two groups, whereas extent of apoptosis in the EMPA group was lower than other two groups. The data suggested that SGLT2 inhibitors could alleviate cold ischemia damage of mitochondria in fatty liver, which may be related to the inhibition of apoptosis and the activation of P-STAT3 and ALDH2.