Substrates and Electrolytes Dependent Electrocatalytic Performance of Metal Selenides for Hydrogen Evolution Reaction:A Review

The electrochemical skeleton for the production of hydrogen production from water splitting consists of electrocatalysts,electrolytes,substrates,and standard electrodes.Metal selenides have been considered efficient electrocatalysts due to their outstanding features.Moreover,electrolytes and employed substrates can significantly influence the electrocatalytic performance of the metal selenides for hydrogen evolution reaction(HER).Several studies of metal selenides for HERs have been carried out and summarized,but there are some severe limitations regarding the synchronization of the employed substrates,electrolytes,and electrocatalysts.Several experiments suggest that metal selenides deposited on carbon-based substrates inject and transport the charge carriers effectively in an acidic medium and boost the electrocatalytic performance.Meanwhile,the metal selenides deposited on materials other than carbon-based substrates inject and make the facile transportation of the charge carriers in an alkaline medium and promote the electrocatalytic performance.Herein,the fundamental characteristics,critical factors,and electrocatalytic performance of metal selenides deposited on carbon-based substrates in acidic electrolytes have been effectively summarized.The electrocatalytic performance of the metal selenides in an alkaline electrolyte and substrates like nickel foam have also been summarized to provide direction,challenges,and feedback about the electrocatalytic performance of metal selenides.

Recent advances in photonics of threedimensional Dirac semimetal Cd_(3)As_(2)

Due to their unusual features in condensed matter physics and their applicability in optical and optoelectronic applications,three-dimensional Dirac semimetals(3D DSMs)have garnered substantial interest in recent years.In contrast to monolayer graphene,3D DSM exhibits linear band dispersion despite its macroscopic thickness.Therefore,being a bulk material,it is easy to make nanostructures with 3D DSM,just as one normally does with metals such as gold and silver.Among 3D DSMs,cadmium arsenide(Cd_(3)As_(2))is quite famous and considered an excellent 3D DSM due to its chemical stability in air and extraordinary optical response.In this review,advances in 3D DSM Cd_(3)As_(2)fabrication techniques and recent progress in the photonics of 3D DSM Cd_(3)As_(2)are given and briefly reviewed.Various photonic features,including linear and nonlinear plasmonics,optical absorption,optical harmonic generation,and ultrafast dynamics,have been explored in detail.It is expected that Cd_(3)As_(2)would share an excellent tunable photonic response like graphene.We envision that this article may serve as a concise overview of the recent progress of photonics in 3D DSM Cd_(3)As_(2)and provides a compact reference for young researchers.