Skeletal Cu₇S₄ Nanocages Wrapped by Few‐Layered Black Phosphorus Nanosheets as an Efficient H₂ Production Photocatalyst

Abstract

Superstructures with hollow cage‐like hierarchical ordering play a predominant role in various applications owing to their unique properties, such as low density, an interior void, a high surface‐to‐volume ratio, and excellent permeability for charge and mass transport. Low‐cost hollow cage‐like copper sulfide superstructures are competitive candidates for optical and electrochemical applications because of their outstanding conductivity and extensive number of active sites. Thus, we synthesized crystallinity‐controlled nanotwinned polyhedral‐skeletal‐type copper sulfide cages (Cu7S4). Further, these cages were wrapped by few‐layered black phosphorus (BP) nanosheets using simple strategies and tested for photocatalytic hydrogen production. The BP/Cu7S4 hybrid material exhibited improved hydrogen production, i. e., 0.475 μmol h−1, which was 14‐fold greater than that achieved using pristine Cu7S4 cages under optimal conditions. The enhanced activity was attributed to effective charge‐carrier separation and transportation owing to the advanced unique properties of skeletal‐type Cu7S4 cages and few‐layered BP nanosheets. To the best of our knowledge, this is the first report of a BP‐nanosheet‐wrapped Cu7S4 system for photocatalytic hydrogen production. This system combining skeletal hollow cages with BP nanosheets is a new, fascinating, and inspiring approach for photocatalytic water‐splitting applications.

Snowflake-like Cu-BDC-NH2/Cu58S32 Binary Nanohybrid for H2 Evolution and O2 Reduction

“…In addition, the two shake-up satellite peaks are noted at 939.5 and 943.6 eV. The spectral doublet at low BEs is assigned to Cu + species whereas the higher energy doublet corresponds to Cu 2+ ions in the CS lattice (Figure e) . Analogously for pure CM, the peaks due to Cu + species occur at 931.9 and 951.7 eV whereas the spectral characteristics of Cu 2+ ions are observed at 934.4 and 954.2 eV, respectively .…”

Mace‐Shaped Cu7S4 NW/ECF Composites for Photocatalytic Degradation of Antibiotics

“…From Figure 9(b) and (d), the ECF and Cu 7 S 4 are 2.85 eV and 0.08ev [29] . The VB potential value of ECF is 3.32 eV, the CB potential value is 0.4 eV, the VB value of Cu 7 S 4 is 1.04 eV, and the band gap width of Cu 7 S 4 is about 2.1 eV, and the CB value is 1.06 eV [30,31] …”

“…[29] The VB potential value of ECF is 3.32 eV, the CB potential value is 0.4 eV, the VB value of Cu 7 S 4 is 1.04 eV, and the band gap width of Cu 7 S 4 is about 2.1 eV, and the CB value is 1.06 eV. [30,31] Figure 8shows the experimental results of free radical trapping of Cu 7 S 4 NW/ECF composite material. It can be seen from the figure that after adding BQ and TBA, the degradation efficiency of the catalyst are reduced significantly.…”

Electronic Interactions and Charge-Transfer Dynamics for a Series of Yolk–Shell Nanocrystals: Implications for Photocatalysis

“…Considering the typical band alignment scenario at the metal−semiconductor interface, 22 effective charge-carrier separation under light illumination was expected for these yolk−shell nanocrystals. Taking Au@Cu 7 S 4 as an example, since the Fermi level of Au (+0.5 V vs NHE) 52 was less negative than the conduction band edge of Cu 7 S 4 (−1.063 V vs NHE), 53 the resultant band bending at the Au− Cu 7 S 4 interface would drive an opposite charge-transfer direction of photogenerated electrons to that of photoexcited holes, segregating electrons from holes at the interface. Because electrons were separated from holes, their recombination can be further suppressed to depress the PL intensity.…”