Porosity‐Engineering of MXene as a Support Material for a Highly Efficient Electrocatalyst toward Overall Water Splitting

Abstract

The use of 2 D transition metal carbide MXenes as support materials to incorporate catalytically active compounds is of interest because of their unique properties. However, the preparation of well‐dispersed catalytic phases on the inter‐connected porous MXene network is challenging and has been rarely explored. This work focuses on the synthesis of basal‐plane‐porous titanium carbide MXene (ac‐Ti3C2) that is used subsequently as an effective host for the incorporation of a known catalytically active phase (IrCo) as an effective bifunctional electrocatalyst toward water splitting. The porous ac‐Ti3C2 with abundant macro/meso/micropores is prepared by a wet chemical method at room temperature and provides ideal anchor sites for intimate chemical bonding with alien compounds. The resulting IrCo@ac‐Ti3C2 electrocatalyst exhibits an excellent reactivity (220 mV at 10 mA cm−2) towards the oxygen evolution reaction in 1.0 m KOH, which surpasses that of the benchmark RuO2, a low voltage cell of 1.57 V (@ 10 mA cm−2) and good long‐term durability. Our work demonstrates the effectiveness of porosity engineering in MXene nanosheets as a support material to shorten ion migration pathways, to increase electrolyte accessibility between inter‐sheets and to overcome inherited re‐stacking and aggregation issues.

Enhancing N2 Fixation Activity by Converting Ti3C2 MXenes Nanosheets to Nanoribbons

“…MXenes are metal carbide or nitride materials with a two‐dimensional (2D) structure, which attracted a large interest recently for a broad range of applications such as materials for energy and environmental applications, [1–4] and catalysis [5–7] . In the latter area, several papers deal on N 2 fixation (NRR), [8–18] a topic of current large interest to directly produce ammonia from nitrogen [19] .…”

Challenges and Opportunities in Utilizing MXenes of Carbides and Nitrides as Electrocatalysts

“…[ 88 ] PGMs supported on MXenes have been studied for OER, with PtO a PdO b /Ti 3 C 2 T x and IrCo/Ti 3 C 2 T x showing promising OER performance. [ 89,90 ] Non‐precious metals supported on MXenes for OER also draw great attention, especially for Co‐, Ni‐, and Fe‐based catalysts. For instance, strong interfacial interactions between Co 3 O 4 and Ti 3 C 2 T x contribute to improved OER activity and stability.…”

Earth‐Abundant Transition‐Metal‐Based Bifunctional Electrocatalysts for Overall Water Splitting in Alkaline Media

“…demonstrated that the engineering of porous and conductive support effects of 2D transition‐metal carbide MXenes through a wet chemical route could greatly enhance the overall water splitting performance. The improvement can be attributed to the synergistic effect of the porous surface of supporting material with the generated abundant of macro/meso/micropores can only afford high density of well‐distributed active sites but also can efficiently shorten the ion/mass transport migration pathways and increase the electrolyte accessibility in the catalysis …”