In Situ Synthesis of Ag/Ag₂O on CeO₂ for Boosting Electron Transfer in Photocatalytic Hydrogen Production

Abstract

A simple and effective photocatalytic system has always been the goal of photocatalytic research. In this study, Ag/Ag2O was grown in situ on a CeO2 substrate by a one-step method to form a Ag/Ag2O/CeO2 photocatalyst. The close combination of the two made the composite catalyst have more effective hydrogen evolution sites. The Ag/Ag2O/CeO2 composite catalyst has a wide light absorption wavelength, low overpotential, and small electrochemical impedance, which are favorable for the development of a photocatalytic system. CeO2 and Eosin Y continue to provide photogenerated electrons as electron donors, while the heterostructure of the Ag/Ag2O/CeO2 system enables the separation of electrons on the conduction band of CeO2. The ingenious coordination of the two can effectively isolate the photogenerated electron–hole pairs, thus supporting the continuous progress of photocatalytic hydrogen evolution. Importantly, Ag/Ag2O/CeO2 has excellent photocatalytic performance for hydrogen production; in particular, Ag/Ag2O/CeO2-30 has the highest hydrogen production efficiency, which is much higher than those of Ag/Ag2O and CeO2. Therefore, Ag/Ag2O/CeO2 can be considered as a photocatalyst worth developing.

Graphdiyne (CnH2n−2) coupled with ZnCo-MOF double S-scheme heterojunction forms an efficient electron transport layer and its characterizationvia in situXPS

“…The Catalysis Science & Technology Paper black pair has a strong absorption capacity for all light. 59 The same can be seen in Fig. 7b, where all the other catalysts have good light absorption due to the fact that all the catalysts are black and black absorbs all wavelengths of light.…”

Mechanochemical preparation of graphdiyne (CnH2n−2) based Ni-doped MoS2S-scheme heterojunctions within situXPS characterization for efficient hydrogen production

“…70–72 Under the irradiation of visible light, the electrons on GDY and NM-3 VB were excited to transfer to the CB, and under the compound effect of the built-in electric field and Coulomb force pushing and the energy band bending hindering their own electron holes, the photogenerated electrons on NM-3 CB migrated to the VB of GDY and combined with the photogenerated holes produced by GDY, so that the low hydrogen precipitation potential of GDY is retained, while the photogenerated holes left in NM-3 were consumed by the sacrificial reagent TEOA. 73,74 EY was excited to EY 1 *, which was converted to the more stable EY 3 * by ISC; EY 3 * gained electrons from the sacrificial reagent TEOA to the strongly reducing EY − *; and EY − * transferred electrons to the VB of the catalyst to change back to the ground state EY, while the electrons transferred to the VB of GDY were finally involved in the hydrogen precipitation reaction. 53,75–77…”

Rational Construction of Electrostatic Self‐Assembly of Metallike MoP and ZnIn2S4 Based on Density Functional Theory to Form Schottky Junction for Photocatalytic Hydrogen Production

“…[9] The photocatalytic reaction low density of solar energy can be transformed to a high density of the hydrogen; based on various factors of thinking, the use of a steady stream of solar energy resources for photocatalytic decomposition of water to produce hydrogen by the countries all over the world high attention, which has good prospects for development, is expected to be in more areas to industrial application. [10][11][12][13][14][15] As a member of AB 2 X 4 semiconductor family, ZnIn 2 S 4 has attracted wide attention due to its advantages of low toxicity, sufficient raw materials, simple chemical composition, mild reaction process, etc., and has been applied in many fields such as energy environment, absorbing materials, photocatalysis, etc. [16][17][18] Like other sulfides, it has good visible light response ability, its bandgap is adjustable in the range of 2.06-2.85 eV, which has a suitable conduction band (CB) potential for hydrogen evolution reaction.…”