Single metal atoms catalysts—Promising candidates for next generation energy storage and conversion devices

Abstract

Single-metal-atom catalysts (SMACs) with the merits of maximum atom utilization, peculiar electronic structure, and adjustable coordination environment, have emerged as the rising stars. They are not only regarded as the promising electrocatalysts, but also show unconventionally excellent alkali storage, thus enabling them for energy devices. In this work, we review the up-to-date progress of single metal atom catalysts including the detailed synthetic strategies and all sorts of applications in energy storage and conversion. In addition, we also discuss intrinsic catalytic effects, degradation mechanism, modulation approaches, support structure design, current challenges, and potential development trends. This work may shed light on developing high-performance SMACs using a variety of strategies for catalytic and energy applications.

Ruthenium single‐atom modulated Ti3C2Tx MXene for efficient alkaline electrocatalytic hydrogen production

“…Impressively, Ru SA @Ti 3 C 2 T x demonstrates an almost exponentially increased TOF trend with cathodic potentials, signifying its superior capability under high current densities. It has been widely recognized that the high mass catalytic activity of SAs‐based catalysts can be advantageously utilized to reduce the catalyst cost, especially for precious noble metals catalysts 35–37,58 . The mass activities achieved by Ru SA @Ti 3 C 2 T x under different cathodic potentials were therefore obtained and compared with the benchmark Pt/C (Figure S6).…”

“…Despite the up-surged research efforts and noticeable progress, the performances of the reported SAs-based HER electrocatalysts are demonstrated mostly at low current densities. [35][36][37] In fact, to the best of our knowledge, the performance of SAs-based HER electrocatalysts at ampere-level current density has not been reported. In addition, due to the lack of in-situ characterization techniques to probe the surface functional groups under operando HER conditions, the activity enhancement mechanism of MXene-supported SAs electrocatalysts remains elusive.…”

“…It has been widely recognized that the high mass catalytic activity of SAsbased catalysts can be advantageously utilized to reduce the catalyst cost, especially for precious noble metals catalysts. [35][36][37]58 The mass activities achieved by Ru SA @-Ti 3 C 2 T x under different cathodic potentials were therefore obtained and compared with the benchmark Pt/C (Figure S6). The mass activities of Ru SA @Ti 3 C 2 T x increase with increasing cathodic potentials, indicating its superior performance under higher current densities.…”

“…It is known that SAs‐based HER electrocatalysts can readily achieve high mass activities, 35–37 however, to achieve high area activities (high current densities) is highly challenging. Despite the up‐surged research efforts and noticeable progress, the performances of the reported SAs‐based HER electrocatalysts are demonstrated mostly at low current densities 35–37 . In fact, to the best of our knowledge, the performance of SAs‐based HER electrocatalysts at ampere‐level current density has not been reported.…”

“…[31][32] The Ru SA -N-Ti 3 C 2 T x electrocatalyst reported by Liu et al can achieve 10 mA cm À2 current density in 0.5 M H 2 SO 4 and 1 M KOH electrolytes under 23 and 27 mV over potentials, respectively. 32 It is known that SAs-based HER electrocatalysts can readily achieve high mass activities, [35][36][37] however, to achieve high area activities (high current densities) is highly challenging. Despite the up-surged research efforts and noticeable progress, the performances of the reported SAs-based HER electrocatalysts are demonstrated mostly at low current densities.…”