Ligand effect on the catalytic activity of porphyrin-protected gold clusters in the electrochemical hydrogen evolution reaction

Abstract

Ligand effect on the catalytic activity of gold clusters in the electrochemical hydrogen evolution reaction.

The role of nanoparticle size and ligand coverage in size focusing of colloidal metal nanoparticles

“…Colloidal synthesis offers a versatile bottom-up approach and has been constantly advancing over the past few decades, with better control over size, shape, composition, super-lattice structure and consequently the nanoparticles' properties (catalytic, electronic, optical, etc.). [1][2][3][4][5][6] For example, recent synthetic methods enabled fabrication of colloidal nanoparticles with different sizes by simply altering the reaction conditions (solvent, ligand, precursor, and synthesis temperature). [7][8][9][10][11] However, since the size distribution of the nanoparticles is oen key to their specic, desired physical and chemical properties, [12][13][14][15][16][17][18] a fundamental understanding of how to control the nucleation and growth is key to enable predictive synthesis of nanoparticles with the desired properties.…”

Gold Nanoclusters as Electrocatalysts for Energy Conversion

“…In addition, using Au n (porphyrin SC 1 P) m NCs, the HER occurred at a smaller overvoltage than using Au n (porphyrin SC 2 P) m NCs. These results indicate that the HER activity of Au n NCs depends on the type of ligand and the distance between the ligand and the metal core in Au n NCs [107]. In this work, the Au n (SR) m NCs with a core size of approximately 2.2 nm showed higher catalytic activity than those with a core size of approximately 1.3 nm ( Figure 3G,H).…”

“…In 2018, Teranishi and Sakamoto et al, used Au n NCs coordinated with SR-containing porphyrin (porphyrin SC x P). They investigated the effects of the ligand structure on the HER activity of Au n (SR) m NCs [107]. In these clusters, the porphyrin ring coordinates horizontally to the gold core.…”

“…Until recently, the materials with relatively high activity for all of HER, OER, and ORR are considered to be limited to Ir, Rh, Ru, and Pt [84,85]. However, the recent studies demonstrated that these properties could also be caused in Au by the discretization of the band structure (e.g., shift of d-band center [107,111]). For Au n NCs, it is possible to precisely control the electronic/geometrical structures and thereby to elucidate the correlation between catalytic activity and electronic/geometrical structure.…”

“…Fine nanoparticle catalysts suitable for the HER [88][89][90][91][92], OER [93][94][95], and ORR [96][97][98][99][100][101] have been developed based on theoretical predictions of activity volcano plots using various metals and alloy nanoparticles (NPs). Au n NCs have recently been observed to possess catalytic activity for the HER, OER, and ORR [77, [102][103][104][105][106][107][108][109][110][111][112][113][114][115][116] (Figure 1). Therefore, Au n NCs are expected to become a model catalyst even in such an energy conversion system.…”