Next‑Generation Green Hydrogen: Progress and Perspective from Electricity, Catalyst to Electrolyte in Electrocatalytic Water Splitting

Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-scale renewable hydrogen production system currently that can compete with conventional fossil fuel hydrogen production.Renewable energy electrocatalytic water splitting is an ideal production technology with environmental cleanliness protection and good hydrogen purity,which meet the requirements of future development.This review summarizes and introduces the current status of hydrogen production by water splitting from three aspects:electricity,catalyst and electrolyte.In particular,the present situation and the latest progress of the key sources of power,catalytic materials and electrolyzers for electrocatalytic water splitting are introduced.Finally,the problems of hydrogen generation from electrolytic water splitting and directions of next-generation green hydrogen in the future are discussed and outlooked.It is expected that this review will have an important impact on the field of hydrogen production from water.

Super rigid tris-spirobifluorenes:Syntheses and properties

In this work,a blue emitter with a 3 D rigid structure composed of multiple spirobifluorene(3-Spiro) has been synthesized and characterized.Through a detailed study of the electrochemical and photophysical properties of 3-Spiro,we have evidenced that 3-Spiro can be applied as an active component of organic light-emitting diodes(OLEDs).The device with 5% doping rate of 4 CzPNPh exhibits high external quantum efficiency(EQE) of 11%,which proves the potential of 3 D rigid structure emitters for OLEDs.

Challenge of biodiesel production from sewage sludge catalyzed by KOH, KOH/activated carbon, and KOH/CaO

The considerable compounds content, abundance, and low costs involved has led to the proposal to use sewage sludge as raw material for biodiesel production. The transesterification reaction is catalyzed using an acid catalyst instead of base catalysts because of the high free fatty acid concentration. However, the use of a base catalyst, particularly a solid base catalyst, has certain advantages, including faster reaction speed and easier separation. In this study, we utilize in situ transesterification by base catalyst （KOH, KOH/activated carbon （AC） and KOH/CaO） with sewage sludge as raw material. Many conditions have been tested to increase biodiesel yield through single-factor tests, including mass fraction and catalyst dosage. Preliminary experiments have optimized reaction time and temperature. However, the three catalysts did not work better than H2SO4, which had a maximum yield of 4.6% （dry sewage sludge base） considering the purity by KOH, KOH/CaO, and KOH/AC. The features of the catalyst were analyzed using XRD, BET and SEM. As to BET of KOH/AC and the good spiculate formation of KOH crystal appears to be essential to its function. As for KOH/CaO, the formation of K20 and absorption points is likely essential.