Polyelemental Nanoparticles as Catalysts for a Li–O₂ Battery

Abstract

The development of highly efficient catalysts in the cathodes of rechargeable Li−O 2 batteries is a considerable challenge. Polyelemental catalysts consisting of two or more kinds of hybridized catalysts are particularly interesting because the combination of the electrochemical properties of each catalyst component can significantly facilitate oxygen evolution and oxygen reduction reactions. Despite the recent advances that have been made in this field, the number of elements in the catalysts has been largely limited to two metals. In this study, we demonstrate the electrochemical behavior of Li−O 2 batteries containing a wide range of catalytic element combinations. Fourteen different combinations with single, binary, ternary, and quaternary combinations of Pt, Pd, Au, and Ru were prepared on carbon nanofibers (CNFs) via a joule heating route. Importantly, the Li−O 2 battery performance could be significantly improved when using a polyelemental catalyst with four elements. The cathode containing quaternary nanoparticles (Pt−Pd−Au−Ru) exhibited a reduced overpotential (0.45 V) and a high discharge capacity based on total cathode weight at 9130 mAh g −1 , which was ∼3 times higher than that of the pristine CNF electrode. This superior electrochemical performance is be attributed to an increased catalytic activity associated with an enhanced O 2 adsorbability by the quaternary nanoparticles.

Noble Metal‐Based Multimetallic Nanoparticles for Electrocatalytic Applications

“…The reliability and generalizability of the technique have facilitated the synthesis of other HEA nanoparticles comprising various combinations of elements. [ 114 , 115 , 116 , 117 , 118 ]…”

“…The reliability and generalizability of the technique have facilitated the synthesis of other HEA nanoparticles comprising various combinations of elements. [114][115][116][117][118] Lu and co-workers suggested that pyrolysis using a fastmoving bed is a reliable synthetic method for synthesizing HEA nanoparticles on granular supports (Figure 8b). [119] In this method, a boat containing precursor-loaded support was moved into the center of the furnace preheated to 923 K with a propulsion speed of ≈20 cm•s −1 .…”

Searching for an Optimal Multi‐Metallic Alloy Catalyst by Active Learning Combined with Experiments

“…Third, the direct incorporation of nonmetallic components (e.g., carbon) into the metal active sites introduces serious complexity in terms of reliable calculations, although studies have reported that encapsulating graphene layers contribute to the catalytic performance. [35,36] Finally, computational calculations of multi-metallic unit cells are expensive owing to the necessity of large unit cells and the extensive requirement for k-vectors in the reciprocal space. As a result, errors from these uncertainties propagate through the computational process and introduce significant bias and epistemic uncertainty in the modeling; hence, the current metallic catalyst databases and ML techniques are not suitable for the universal exploration of multi-metallic alloy catalysts.…”

Generation of high-density nanoparticles in the carbothermal shock method

“…The time during which the temperature rises and falls is very short, and so it is a very innovative way of mixing multiple metals with small and uniform NPs (1). The ability to synthesize a desired NP can open exciting new possibilities for studying polyelemental NPs, and this method has already enabled notable applications such as rechargeable energy storage systems (e.g., Li and Na ion batteries, supercapacitors, and Li-CO 2 and Li-O 2 batteries), electrochemical water splitting (e.g., oxygen evolution reaction), and electrocatalysis (e.g., hydrogen evolution, oxygen reduction, and carbon monoxide reduction reactions) (2)(3)(4)(5)(6)(7)(8).…”