A General Strategy toward Metal Sulfide Nanoparticles Confined in a Sulfur‐Doped Ti₃C₂T_x MXene 3D Porous Aerogel for Efficient Ambient N₂ Electroreduction

Abstract

Three‐dimensional (3D) porous MXene‐based aerogel architectures have attracted great interest for many applications, despite limits in renewable energy conversion owing to the lack of multifunctionality in their components. Herein, a simple and general strategy for constructing a novel functional 3D MXene‐based composite heterojunction aerogel (MS@S‐MAs) is presented via divalent metal‐ion assembly and subsequent thermal sulfidation, and its application in electrochemical nitrogen reduction reaction (NRR) is studied. The as‐prepared MS@S‐MAs comprises metal sulfide nanoparticles uniformly confined in 3D interconnected conductive S‐doped MXene sheets with intimate interfacial interaction. Benefiting from the unique properties and an interfacial interaction, MS@S‐MAs exhibit significantly improved NRR catalytic performance and excellent stability because of the higher exposure of electrochemically active sites coupled with easier accessibility, faster mass diffusion, and quicker carrier transport at the interface. Remarkably, CoS@S‐MAs show an NH3 yield rate and a Faradaic efficiency of 12.4 µg h−1 mg−1cat and 27.05% at the lower potential of −0.15 V versus a reversible hydrogen electrode in 0.1 m Na2SO4 solution under ambient conditions, which rivals or exceeds most of the previously reported MXene‐based and Co‐based catalysts. This work will open avenues to construct 3D MXene‐based materials with rich functionalities for energy storage and conversion, catalysis, and other applications.

Molten Salts Etching Route Driven Universal Construction of MXene/Transition Metal Sulfides Heterostructures with Interfacial Electronic Coupling for Superior Sodium Storage

“…The strong electronic coupling within the heterointerfaces can significantly boost the interfacial electron transfer and ensure the intimate contact between Ti 3 C 2 T x and FeS 2 . [24,27,28,31] The XPS spectra of Ti 3 C 2 T x /CoS y and Ti 3 C 2 T x /NiS y as well as discussion part are depicted in Figures S7 and S8, Supporting Information.…”

“…For instance, a tedious fabrication process is required for MXene/TMSs heterostructures, generally including the preparation of multi-layered or few-layered MXenes, subsequent electrostatic adsorption of metal ions on the surface of MXenes, and final post-treatments. [24,27,[29][30][31] In addition, the preparation process of MXene/TMSs heterostructures usually requires the utilization of hazardous HF, water, or other solvents, which greatly reduces the experimental safety and may lead to the unwanted oxidation and degradation of MXenes. [30,32] The abovementioned two issues considerably restrict the efficient preparation and wide application of MXene/TMSs anodes.…”

Defect and interface engineering in metal sulfide catalysts for the electrocatalytic nitrogen reduction reaction: a review

“…6F). 87 Due to the intimate interfacial interaction between CoS and MXene, and the fast mass transport channel provided by the 3D interconnected MXene, the CoS@S-MAs exhibited a high NH 3 yield of 12.4 mg h À1 mg cat À1 with a FE of 27.05% at À0.15 V in 0.1 M Na 2 SO 4 , much higher than those of MXene and the mixture of CoS and MXene, demonstrating the important role of interface engineering (Fig. 6G).…”

In situgrowth of 2D ZnIn2S4nanosheets on sulfur-doped porous Ti3C2TxMXene 3D multi-functional architectures for photocatalytic H2evolution

“…The diffraction peak (002) plane of S-doped Ti 3 C 2 T x is significantly widened than that of the few-layered pristine Ti 3 C 2 T x nanosheets, which emphasizes that the formation of a 3D porous architecture can effectively prevent the aggregation of the Ti 3 C 2 T x sheets. 34 The XRD pattern of S-Ti 3 C 2 T x @ZnIn 2 S 4 composites represents a coexistence of the diffraction peaks of This journal is © The Royal Society of Chemistry 2022 S-doped Ti 3 C 2 T x and ZnIn 2 S 4 . The main characteristic diffraction peaks are located at 27.61 and 47.11, which are in agreement with the (102) and (110) lattice planes of the hexagonal ZnIn 2 S 4 phase (JCPDS No.…”

“…To date, the research of 2D layered Ti 3 C 2 T x in the field of photocatalysis has made considerable progress. However, Ti 3 C 2 T x nanosheets are prone to lamellar agglomeration under strong van der Waals forces and hydrogen bonding interactions, 34 thereby resulting in high interface resistance, insufficient catalytic active sites, greatly limiting applications in surface-related photocatalytic reactions. Inspired by the fact that three-dimensional (3D) graphene framework structures can be composed of 2D graphene nanosheets, 35 the integration of 2D large-scale and mono-layer MXene nanosheets as building blocks into 3D porous scaffolds is regarded as a promising strategy, which effectively inhibits the restacking of MXene nanosheets.…”