The effects of the fluence of electron irradiation on the structure and hydrogen evolution reaction performance of molybdenum disulfide

Abstract

Controllable and stable 1T phase MoS2 nanosheets were obtained by 1 MeV electron irradiation, and the hydrogen evolution reaction performance was improved.

Effects of 60Co γ-ray irradiation of thin-layer molybdenum disulfide for the hydrogen evolution reaction

“…The corresponding Tafel slopes were plotted from the Tafel equation ( η = b log|Δ j | + a , where η is the overpotential, Δ j is the current density, a is the Tafel constant and b is the Tafel slope). 21 As shown in Fig. 5b, from the extrapolation of η versus log| j |, we obtained Tafel slopes for MoS 2 after irradiation at a dose of 10 Mrad, exhibiting a minimum Tafel slope of 65.96 mV dec −1 , less than those of bare MoS 2 (130.88 mV dec −1 ) and MoS 2 irradiated at 100 krad (121.23 mV dec −1 ), 1 Mrad (74.97 mV dec −1 ) and 100 Mrad (78.48 mV dec −1 ), respectively.…”

“…In view of the difficulty of achieving optimal catalytic performance only from the intrinsic MoS 2 structure, finding effective methods to improve its surface activity becomes a crucial issue. 15 Recently, various strategies have been explored to effectively achieve material structure modulation, [16][17][18][19][20] defect introduction, 14,[21][22][23][24][25] doping, [26][27][28][29][30][31] phase transfer, 32,33 etc., thus promoting the catalytic performance. However, because of the inevitable appearance of second phases and impurities during conventional chemical synthesis methods, the type of dopant is also limited, and the 1T structure is metastable, which will cause the catalyst to be unstable for long-time reactions.…”

“…In view of the difficulty of achieving optimal catalytic performance only from the intrinsic MoS 2 structure, finding effective methods to improve its surface activity becomes a crucial issue. 15 Recently, various strategies have been explored to effectively achieve material structure modulation, 16–20 defect introduction, 14,21–25 doping, 26–31 phase transfer, 32,33 etc. , thus promoting the catalytic performance.…”

Defect Engineering of MoS2 Nanosheets by Heavy-Ion Irradiation for Hydrogen Evolution

“…Finally, the precipitate was dried in a vacuum oven at 65 °C for 12 h to form the as-prepared MoS 2 . The details can also be found in the literature, and the only difference is the purity of the raw materials used in this study.…”

“…This indicates that a high density of surface defects results in a relatively disordered atomic arrangement, decreasing the crystal symmetry and crystallinity of MoS 2 NSs. 25,59 Furthermore, XPS was performed on the bare MoS 2 and F − -2 × 10 13 samples to study the chemical composition and valence state of MoS 2 NSs before and after irradiation. As shown in Figure 4a, the F 1s peak is observed at ∼688 eV in the XPS spectrum of F − -2 × 10 13 ; however, F 1s does not exhibit a clear peak in the XPS spectrum, probably because XPS is a surface-sensitive spectroscopic technique, and its penetration depth is less than ∼10 nm.…”