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Zirconium phosphate (ZrP) nanomaterials have been studied extensively ever since the preparation of the first crystalline form was reported in 1964. ZrP and its derivatives, because of their versatility, have found applications in several fields. Herein, we provide an overview of some advancements made in the preparation of ZrP nanomaterials, including exfoliation and morphology control of the nanoparticles. We also provide an overview of the advancements made with ZrP as an inorganic support for the electrocatalysis of the oxygen evolution reaction (OER). Emphasis is made on how the preparation of the ZrP electrocatalysts affects the activity of the OER. 

A cobalt porphyrin molecule, namely CoTcPP (TcPP = the dianion of meso -tetra(4-carboxyphenyl)porphyrin), is intercalated into zirconium phosphate (ZrP) layers as an effective way to heterogenize a porphyrin-based molecular electrocatalyst. Fourier-transform infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRPD) measurements, UV-Vis spectroscopy, elemental mapping, energy dispersive X-ray (EDX) analysis, inductively coupled plasma mass spectrometry (ICP-MS) and X-ray photoelectron spectroscopy (XPS) were utilized to determine the successful intercalation of CoTcPP into ZrP. While the CoTcPP molecule is not amendable to be used as a heterogeneous catalyst in basic environment due to the carboxylic groups, the intercalated species (CoTcPP/ZrP) is effective towards water oxidation from KOH aqueous solution when utilized as a heterogeneous electrocatalyst and shows remarkable catalytic durability. Electrochemical results show that CoTcPP/ZrP requires an overpotential of 0.467 V to achieve a current density of 10 mA cm −2 while the pristine α-ZrP shows negligible electrocatalytic OER behavior. 

The conversion of solar energy into chemical fuel is one of the “Holy Grails” of 21st century chemistry. Solar energy can be used to split water into oxygen and protons, which are then used to make hydrogen fuel. Nature is able to catalyze both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) required for the conversion of solar energy into chemical fuel through the employment of enzymes that are composed of inexpensive transition metals Instead of using expensive catalysts such as platinum, cheaper alternatives (such as cobalt, iron, or nickel) would provide the opportunity to make solar energy competitive with fossil fuels. However, obtaining efficient catalysts based on earth abundant materials is still a daunting task. Progress in finding an ideal catalyst for the OER has been challenging as it appears that the overpotential for these catalysts have plateaued. Recent theory has shown that nanoscopic confinement of catalysts into 3D frameworks increases stability and efficiency of catalysts for OER. We are studying the use of the layered inorganic nanomaterial zirconium phosphate (ZrP) for water splitting. In this chapter we review the advancements made with ZrP as a support for transition metals for the OER. Our studies have found that ZrP is a suitable support for transition metals as it provides an accessible surface where the OER can occur. Further findings have also show that exfoliation of ZrP increases the availability of sites where active species can be adsorbed and performance is improved with this strategy. 

The electrochemical oxygen evolution reaction (OER) is the half-cell reaction for many clean-energy production technologies, including water electrolyzers and metal–air batteries. However, its sluggish kinetics hinders the performance of those technologies, impeding them from broader implementation. Recently, we reported the use of zirconium phosphate (ZrP) as a support for transition metal catalysts for the oxygen evolution reaction (OER). These catalysts achieve promising overpotentials with high mass activities. Herein, we synthesize ZrP structures with controlled morphology: hexagonal platelets, rods, cubes, and spheres, and subsequently modify them with Co( ii ) and Ni( ii ) cations to assess their electrochemcial OER behavior. Through inductively coupled plasma mass-spectrometry measurements, the maximum ion exchange capacity is found to vary based on the morphology of the ZrP structure and cation selection. Trends in geometric current density and mass activity as a function of cation selection are discussed. We find that the loading and coverage of cobalt and nickel species on the ZrP supports are key factors that control OER performance.