ZIF ‐67 derived hollow double‐shell core Co ₃ O ₄ modified g‐C ₃ N ₄ to construct p‐n heterojunction for efficient photocatalytic hydrogen evolution

Abstract

Summary The imidazolium salt zeolite framework (ZIFs) organometallic framework materials have the advantages of high stability and controllable structure and are excellent materials for preparing photocatalytic semiconductors. In this study, the regular dodecahedron material ZIF‐67 was used as the substrate, and the intermediate was calcined after the substrate adsorbed Co‐based metal clusters to obtain Co3O4 with a hollow double‐shell structure. Through SEM and fluorescence detection, it can be seen that the Co3O4 material obtained by this method not only has a unique spatial morphology but also shows a strong light absorption performance and a high charge transfer rate. In addition, graphite‐like phase carbon nitride (g‐C3N4), as a traditional catalyst, has been unable to move toward industrialization due to its low electron utilization and light absorption properties. So here, the composite catalyst CNCO‐x (x = 1, 2, 2, 3, 4, and 5) was prepared by simply anchoring Co3O4 and g‐C3N4 to improve the catalytic performance of g‐C3N4. The results show that the introduction of Co3O4 not only improves the electron utilization of g‐C3N4 but forms a charge transfer bridge channel (p‐n heterojunction) after contact between the two, which effectively promotes the rapid transfer of photoelectrons between the contact interfaces. Finally, when the amount of Co3O4 introduced is 15%, the amount of hydrogen produced in 5 hours can reach 0.163 mmol (3.26 mmol g−1 hour−1), which is 163 times that of pure g‐C3N4.

Graphdiyne (g‐CnH2n−2)‐Supported Organic–Inorganic Composites with Zinc Cadmium Sulfide for Photocatalytic Hydrogen Evolution

“…This means that the tested samples are microporous and mesoporous materials. [ 62 ] The specific surface area, pore size, and pore volume are shown in Table 1 . Among them, the change in pore volume and pore diameter is small and can be ignored.…”

Efficient full solar spectrum-driven photocatalytic hydrogen production on low bandgap TiO2/conjugated polymer nanostructures

“…41,42 Highly porous structures have also been previously reported to not only enhance efficient diffusion of reactants but also improve visible light absorption. 29,43 To further conrm the lowering of bandgap and improvement in the light absorption of the materials aer the incorporation of PPy, UV-DRS measurements have been conducted and the bandgaps of the materials was estimated (Fig. 4b-d).…”

“…27,28 Several researchers have also reported enhanced visible light utilization in highly porous nanostructures because the light bounces back and forth in the cavities allowing more time for absorption and the photoinduced carriers have a higher mobility inhibiting charge recombination. 29,30 However, till date, harvesting solar light in the entire spectrum (UV to NIR) has still not been fully solved and the practical application of TiO 2 under solar irradiation remains unrealized. Therefore, it is believed that preparing a highly mesoporous TiO 2 (m-TiO 2 ) catalyst that allows sunlight to diffuse faster through its pores and coupling this catalyst with a visible light-active conjugated polymer such as polypyrrole (PPy) 31 will be a particularly promising way to enhance solar light response of the photocatalyst for H 2 production.…”

Co3O4 Nanocrystals Coupled with Co-Doped TiO2 Nanobelts as a Synergistic Photocatalyst for Efficient Photoconversion of CO2 and H2O to Solar Fuels

“…In particular, these nanostructures heighten the surface-to-volume ratios and shorten the migration distance for charges to improve the overall transport properties of charge carriers. , Moreover, coupling semiconductors to these nanostructures has also turned out to be another effective design strategy for simultaneously achieving a suitable conduction band, valence band, and charge separation capacity. Especially, p–n heterojunction systems formed by a multi-semiconductor hybrid are considered as a promising method for maintaining the redox ability and exhibiting efficient spatial separation of charge carriers . Through a p–n heterojunction, oxidation and reduction catalytic centers are more active to minimize the undesirable backreaction .…”

“…Especially, p−n heterojunction systems formed by a multi-semiconductor hybrid are considered as a promising method for maintaining the redox ability and exhibiting efficient spatial separation of charge carriers. 19 Through a p−n heterojunction, oxidation and reduction catalytic centers are more active to minimize the undesirable backreaction. 20 The valence change behavior of is obtained by adding 0.5 mL of HCl to the hydrothermal reaction system under the same conditions as described above.…”