Data on a high electrocatalytic activity of metal-WO3 nanocomposite electrocatalysts for hydrogen evolution reaction

The data of this article provides information on the synthesis of metal-WO3 nanocomposites used as electrocatalysts for hydrogen evolution reaction (HER). Hydrogen can be used as an energy carrier, however, it does not typically exist by itself in nature. Therefore, hydrogen must be produced from the compounds that contain it. Water splitting via renewable energy is a promising pathway to produce hydrogen [1-5]. The important thing about this pathway is developing a catalyst to enhance water-splitting efficiency and reduce the cost of hydrogen production. Currently, WO3-based material has emerged as a good candidate catalyst for the HER [6-7]. In this work, we present a method to prepare metal-WO3 materials and analyze their characterizations and electrochemical properties. Figure 1 shows a scheme of the synthesis process of metal-WO3 nanocomposites. Figure 2 describes the different colors of the reactors before and after the synthesis. Figure 3 and Figure 4 present the morphology and structure of metal-WO3 nanocomposites by SEM and TEM images. Figure 5 supplies the survey XPS spectra taken from metal-WO3 material to disclose the electronic structure of metal-WO3 nanocomposites by using the XPS spectra. Table 1 indicates the detailed values of the electrochemical performance of metal-WO3 catalysts in the acidic electrolyte during the hydrogen evolution reaction (HER) process. The metal-WO3 catalysts were prepared as can be seen in Figure 1. The change of colors of reactors as shown in Figure 2 suggests that metal-WO3 catalysts were successfully synthesized. The SEM and TEM images show that metal nanoparticles (Pd, Au, Ru, Ni, and Rh) deposited on WO3 nanosheets as can be seen in Figure 3 and Figure 4. Figure 5 is the XPS survey of the Rh-WO3 sample and other metal-WO3 samples. The deconvolution of the Rh peak attributed to metallic Rh at 531 eV and 532.4 eV, confirmed that the Rh nanoparticle was successfully on WO3 nanosheets [1]. Then the metal-WO3 catalysts were measured HER performance following the method from previous work [8]. The role of the hydrogen spillover effect on the HER activity was proved by measuring the HER performance of prepared metal-WO3 catalysts and comparing it with metal catalysts without WO3 in previous work [9-16]. As a result, metal-WO3 catalysts exhibit excellent HER activity with only 5wt% of metal deposited on WO3 nanosheets. The overpotential values of 456, 273, 141, 192, and 48 mV to obtain a current density of 10 mA.cm-2 in the acidic electrolyte for Ni-WO3, Au-WO3, Pd-WO3, Ru-WO3, and Rh-WO3; respectively. Especially, Rh-WO3 (5wt% of Rh) displayed excellent HER activity with the overpotential value of 48 mV compared with that of the commercial Pt/C (20wt% of Pt) due to the effect of hydrogen spillover on WO3 [1, 6, 7]. Therefore, the low loading of metal combined with the hydrogen spillover effect can be a promising strategy to develop HER catalysts for water splitting to produce sustainable hydrogen.