Intercalation engineering of MXenes towards highly efficient photo(electrocatalytic) hydrogen evolution reactions

Abstract

The emergent of 2D MXenes composed of transition metal carbides, nitrides or carbonitrides has brought spurious scientific interests in the recent years. Its unique layered structure and highly configured surface...

Additive-mediated intercalation and surface modification of MXenes

“…It is worth noting that the H 2 O molecule is the most common intercalant for MXenes. 72,73 Almost all intercalation behaviors are accompanied by the intercalation of H 2 O. Combined with ultrasonic treatment, the yield of small-size and thin-layer MXene flakes can significantly increase.…”

“…It is well known that MXenes have abundant and adjustable surface terminal groups (T x = –F, –OH, and –Te), and many research groups are dedicated to enhancing the optical, electrical, magnetic, piezoelectric, and thermoelectric properties via chemical modification of these surface terminal groups. To date, the surface terminal groups of MXene-based materials can be categorized into the following groups: halogen terminal functional groups (–F, –Cl, –Br), chalcogen terminal functional groups (–OH, –O–, –S, –Se, –Te), imino (–NH), and vacancy terminal functional groups, 10–13,52–54,73–93 as illustrated in Fig. 3(a–c).…”

Energetic Stability and Interfacial Complexity of Ti3C2Tx MXenes Synthesized with HF/HCl and CoF2/HCl as Etching Agents

“…Indeed, it is a common phenomenon that cationic intercalation increases the interlayer distances of MXenes, leading to reduced layer-layer van der Waals forces. 35,37,73 Because of the larger distribution of the interlayer distances of CoF2-MXene, particularly the increased interlayer distance due to pillaring, the layer-layer van der Waals forces are not as strong. Consequently, the carbide layers of CoF2-MXene tend not to stabilize each other as much as those layers of HF-MXene that are uniformly apart and with smaller interlayer distances.…”

“…Nevertheless, the roles of different interlayer species and the guest-host interfacial chemistry play in determining thermodynamic, structures, and interfacial properties of MXene materials have not been systematically explored. [35][36][37][38] There has been progress towards investigating water/ion-layer interactions, yet the energetics of intercalated particle -MXene layer interactions and why they present higher exothermic formation enthalpies from elements than the bulk parent MAX phases after synthesis and high-temperature treatments have not been clearly understood. 11,[39][40][41][42][43] In other words, unlocking MXene's full potential requires an improved understanding of the energetic interplay of intercalants, surface chemistry, and specific layered structures for samples synthesized under different etching conditions and with varied etching agents.…”

Unveiling the mechanism of high-performance hydrogen evolution reaction on noble-metal-free (113)-faceted Ni3C: ab initio calculations

“… 1–4 Because of the environmental friendliness, recycling utilization and high-energy capacity of hydrogen (H 2 ) fuels, H 2 has been considered as a green and potential new energy carrier over the past few decades. 5 To date, hydrogen evolution reaction (HER) by water splitting, including electrocatalysis 6 and photocatalysis, 7,8 has been regarded as a pivotal technique to resolve the energy and environmental-related problems. At present, noble metals ( e.g.…”