Dislocation‐Strained IrNi Alloy Nanoparticles Driven by Thermal Shock for the Hydrogen Evolution Reaction

Abstract

An efficient manner to produce strained atomic structures, is fabricating catalysts with defect-rich atomic structures, including surface defects (such as surface vacancy, doping,) and bulk defects (such as dislocations and grain boundary). [3] Traditional methods to synthesize strain-effected structures, including polyol synthesis, seed-mediated growth, galvanic replacement, electrochemical dealloying, and thermal annealing-induced segregation, [2i,4] are complex and time-consuming processes, which hinder the manufacturing efficiency and limit the wide application of strain-effected catalysts. In addition, strain-induced high-energy surface structures arising from bulk defects, such as dislocations or grain boundary, are more likely to be resistant to surface restructuring during catalysis. [5] It is generally accepted that non-equilibrium conditions tend to induce plentiful defects, so we seek to employ a synthesis method in an extreme environment to realize bulk-defect-strained structures of electrocatalysts. Recently, our group developed a thermal shock nanomanufacturing method which showed enormous potential and achieved great progresses in ultrafast fabrication of nanoparticles, nanowires, graphene, and more. [6] Since the thermal shock process was invented, the method has been widely used in nanomaterials production. [6a-e,7] However, few studies focused on how Designing high-performance and low-cost electrocatalysts is crucial for the electrochemical production of hydrogen. Dislocation-strained IrNi nanoparticles loaded on a carbon nanotube sponge (DSIrNi@CNTS) driven by unsteady thermal shock in an extreme environment are reported here as a highly efficient hydrogen evolution reaction (HER) catalyst. Experimental results demonstrate that numerous dislocations are kinetically trapped in self-assembled IrNi nanoparticles due to the ultrafast quenching and different atomic radii, which can induce strain effects into the IrNi nanoparticles. Such strain-induced highenergy surface structures arising from bulk defects (dislocations), are more likely to be resistant to surface restructuring during catalysis. The catalyst exhibits outstanding HER activity with only 17 mV overpotential to achieve 10 mA cm −2 in an alkaline electrolyte with fabulous stability, exceeding state-of-the-art Pt/C catalysts. These density functional theory results demonstrate that the electronic structure of as-synthesized IrNi nanostructure can be optimized by the strain effects induced by the dislocations, and the free energy of HER can be tuned toward the optimal region. Hydrogen, as a clean energy source with a high energy density, opens up the opportunities of renewable energy and traditional fossil energy, increasing the diversification of energy sources. [1] Nevertheless, the improvement of hydrogen production is limited toward overpotential and stability due to the intrinsically sluggish kinetics of the hydrogen evolution reaction (HER). Strain engineering, which can optimize the electronic structure and chemical activity of the ...

Co‐Constructing Interfaces of Multiheterostructure on MXene (Ti3C2Tx)‐Modified 3D Self‐Supporting Electrode for Ultraefficient Electrocatalytic HER in Alkaline Media

“…The d‐band center (ε d ) is often used as the describer to demonstrate the binding strength of adsorbates on catalyst surfaces. [ 35,36 ] Figure 4c shows that the ε d of CP@TC (‐1.57 eV) and CPN@TC (‐1.71 eV) are further away from the Fermi level compared with that of CP (‐1.53 eV) unambiguously. Therefore, it can be considered that the binding interaction between H* and CPN@TC becomes weaker according to the d‐band theory, [ 36 ] and it is consistent with UPS analysis.…”

“…[ 35,36 ] Figure 4c shows that the ε d of CP@TC (‐1.57 eV) and CPN@TC (‐1.71 eV) are further away from the Fermi level compared with that of CP (‐1.53 eV) unambiguously. Therefore, it can be considered that the binding interaction between H* and CPN@TC becomes weaker according to the d‐band theory, [ 36 ] and it is consistent with UPS analysis. In addition, the electron orbital of interface atoms in heterojunction will be regulated by the charge redistribution and transfer of the multi‐heterostructure interfaces of CPN@TC.…”

Controllable synthesis and electrocatalytic applications of atomically precise gold nanoclusters

“…So far, researchers have reported a number of HER catalysts with excellent performance, even some performance exceeding commercially available Pt/C catalysts. [98][99][100] However, there is much to be explained about the interaction between hydrogen and metal for these catalysts. Atomically precise Au NCs provide an ideal template for the mechanism of HER reaction.…”

Challenges and Opportunities for Seawater Electrolysis: A Mini-Review on Advanced Materials in Chlorine-Involved Electrochemistry

“…Alternatively, hydrogen production from water electrolysis powered by renewable energies can provide a new approach for the current energy framework without compromising the long-term environmental sustainability 2 . Most water electrolysis systems adopt distilled freshwater with different pH over the past decades [3][4][5][6] , which is not an ideal approach in the regions with deficient freshwater supply but plenty of available seawater. From a practical point of view, direct seawater electrolysis has tremendous advantages owing to the abundant storage of seawater on earth and the equal capability to produce high-purity hydrogen.…”