Mesoporous anion-cation-codoped Co₉S₈ nanorings for enhanced electrocatalytic oxygen evolution reactions

Abstract

Recently, the design and synthesis of Co 9 S 8 micro/nanostructures have attracted attention as electrochemical energy storage and conversion devices due to their low cost and environmental friendliness. Herein, Co 9 S 8 nanorings were synthesized via a one-step solvothermal method with the incorporation of Fe ions, subsequently, properly selenized to boost their electrocatalytic performance. The morphology and structure of the series of cation and anion regulated Co 9 S 8 nanorings were characterized, the electrochemical oxygen evolution reaction (OER) properties were assessed. It is worth noting that the as-prepared catalysts, especially the innovative Fe and Se ions double doped Co 9 S 8 nanorings, denoted as Se/Fe-Co 9 S 8 -0.14, exhibited good electrocatalytic OER performance with low overpotential (298 mV) and high durability under alkaline conditions. This work provides a new perspective to develop non-noble metal Co 9 S 8 -based OER electrocatalysts with a superior electrocatalytic performance.

Formation of NiFe-MOF nanosheets on Fe foam to achieve advanced electrocatalytic oxygen evolution

“…The measured potential values were transformed to the reversible hydrogen electrode (RHE) by using the Nernst equation (E RHE = E Ag/AgCl + 0.197 V + 0.059 × pH). The overpotential (η) was obtained by using the formula: η = E RHE − 1.23 V. [34][35][36] All polarization curves in this work have been calibrated by IR compensation. Electrochemical impedance spectroscopy (EIS) was performed at a voltage of 1.51 V vs. the RHE and in the frequency range from 100 kHz to 100 mHz.…”

Surface Engineering of 2D Carbon Nitride with Cobalt Sulfide Cocatalyst for Enhanced Photocatalytic Hydrogen Evolution

“…For the Co 2 p spectra of Co 9 S 8 , the peaks at 778.5 and 793.6 eV correspond to Co 3+ in Co 2 p 3/2 and Co 2 p 1/2 , respectively, and the peaks at 781.6 and 797.6 eV correspond to Co 2+ in Co 2 p 3/2 and Co 2 p 1/2 , respectively, in Figure 3c. [ 41,52,53 ] For the composite, a pair of new characteristic peaks appeared at 780.8 and 796.8 eV. The close results show that the characteristic peaks appear at 779.8 and 794.8 eV in the Co 2 p spectra of pure CoN (Figure S5a, Supporting Information).…”

“…In Figure 3d, the peaks at 161.4 and 162.5 eV correspond to Co─S in S 2p 3/2 and Co 2p 1/2 , respectively, in pure Co 9 S 8 . [52,54,55] The other peaks in pure Co 9 S 8 correspond to sulfite and sulfate because of the partial oxidization. [41,56] It also happens in the composite material.…”

Sulfur-Treated ITO Back Contact for Enhanced Performance of Semitransparent Ultrathin Cu(In,Ga)Se2 Solar Cells

“…It can be seen in Figure b that multiple S 2p peaks are present at 160.5–165.5 eV, corresponding to the S 2p peak . Two main peaks, S 2p 3/2 and S 2p 1/2 , located at 162.0 and 163.1 eV, respectively, could be indexed to S 2– , , which are related to sulfide bonding . No other satellite peaks representing In–S or Sn–S bond were observed in the range of 152–172 eV.…”

“…36 Two main peaks, S 2p 3/2 and S 2p 1/2 , located at 162.0 and 163.1 eV, respectively, could be indexed to S 2− , 37,38 which are related to sulfide bonding. 39 No other satellite peaks representing In−S 40 or Sn−S 41 bond were observed in the range of 152−172 eV. These findings on the sulfur peaks indicated that sulfur was present on the surface of the ITO substrate in the form of an S−S bond without any significant chemical interaction with the ITO surface.…”