Insight into the Activity and Stability of Rh_xP Nano-Species Supported on g-C₃N₄ for Photocatalytic H₂ Production

Abstract

Transition-metal phosphides have been demonstrated as cocatalysts with great promise for photocatalytic H 2 production materials, but the insurmountable issue remains maintaining outstanding stability while achieving high photocatalytic efficiency. Herein, the rhodium phosphide (RhP x ) nanospecies as cocatalyst is firmly mounted on graphitic carbon nitride (g-C 3 N 4 ) nanosheets to realize the improved activity and stability for photocatalytic H 2 production. The maximum H 2 production rate over RhP x / g-C 3 N 4 driven by visible light diplays a 5.6-fold improvement compared with Pt/g-C 3 N 4 . Meanwhile, the apparent quantum efficiency of 18.4% is achieved at a fixed wavelength of 420 nm that far exceeds the reported g-C 3 N 4 modified with other single-transition-metal phosphides. Particularly, RhP x /g-C 3 N 4 can maintain consistently stable H 2 production when enduring over 25 cyclic reactions with a total of 100 h. The deep insight into the modification effect of RhP x nanospecies reveals that it dramatically facilitates migration and separation of photoinduced electron−hole pairs and heightens interaction at the heterointerfaces between RhP x nanospecies and g-C 3 N 4 nanosheets. This contribution extends the broad potential application of transition-metal phosphides as cocatalysts in the photocatalytic conversion from solar to hydrogen energy.

Ultrathin Mesoporous Carbon Nitride Nanosheets Prepared Through a One‐Pot Approach towards Enhanced Photocatalytic Activity

“…[24][25][26][27] Nevertheless, the photocatalytic activity of pure g-C 3 N 4 is far from satisfaction, which is mainly due to the low-specific surface area and the rapid recombination of photogenerated electron-hole pairs. [28][29][30][31] In the context, various methods are proposed to enhance the photocatalytic performance of g-C 3 N 4 containing increasing specific surface area, morphology control, element doping, heterostructure construction, etc. [32][33][34][35][36][37][38] Among the modification approaches reported, the textural modification is a successful and attractive strategy to improve photocatalytic activity.…”

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

“…The transient photocurrent density of the CuO/tourmaline composite was higher than that of pristine CuO during the repeated switching on and off of light irradiation (Figure 5c), implying that tourmaline could facilitate the transfer of photoinduced e − , which was also confirmed by the PL spectra (Supporting Information File 1, Figure S1). Generally speaking, the higher the transient photocurrent density, the smaller the electrochemical impedance spectra (EIS) [33,34]. According to the time-resolved PL spectra in Figure 5d, the average fluorescence lifetime of the CuO/tourmaline composite (2.94 ns) was shortened with reference to pristine CuO (3.24 ns) ( Table 1).…”

Facile construction of a ZIF-67/AgCl/Ag heterojunction via chemical etching and surface ion exchange strategy for enhanced visible light driven photocatalysis

“…Furthermore, the transfer and separation behaviors of photo induced charge carriers were investigated to explore improvement of photocatalytic activity on the basis of the PL spectra at the excitation wavelength of 338 nm. [33][34][35] As shown in Fig. 7, the observed PL intensity of ZIF-67/AgCl/Ag was much weaker than the other photocatalyst, revealing that ZIF-67/AgCl/Ag had longer lifetime of electron-hole pairs because of surface plasma resonance of Ag 0 .…”