Facile synthesis of laminated porous WS2/C composite and its electrocatalysis for oxygen reduction reaction

The Vulcan XC-72R modified WS2 nanocomposite (WS2/C）was prepared by solid reaction process combined with sonication. The as-prepared WS2/C nanocomposite presents a laminated porous structure by SEM and TEM characterization. The electrochemical experiments show that the onset potential and the limiting-current density of WS2/C is 0.78 V and 4.99 mA cm−2, respectively, which is much higher than, WS2 (3.12 mA cm−2) and Vulcan XC-72R (2.79 mA cm−2). The number of transfer electrons in ORR at the WS2/C nanocomposite electrode is 3.70, which is close to four-electron process. Besides, the current density of WS2/C nanocomposites remained at 90% after 20,000 s, indicating its superior electrochemical stability. All these facts reveal that the as-prepared WS2/C nanocomposite can be regarded as a promising cathode ORR catalyst for fuel cell.