Pd-Decorated 2D MXene (2D Ti3C2Tix) as a High-Performance Electrocatalyst for Reduction of Carbon Dioxide into Fuels toward Climate Change Mitigation

Abstract

Palladium nanoparticles (Pd NPs) have attracted considerable attention recently for their excellent catalytic properties in various catalysis reactions. However, Pd NPs have some drawbacks, including their high cost, susceptibility to deactivation, and the possibility of poisoning by intermediate products. Herein, Pd nanoparticles with an average diameter of 6.5 nm were successfully incorporated on electronically transparent 2D MXene (Ti3C2Tix) nanosheets (Pd-MXene) by microwave irradiation. Considering the synergetic effects of ultra-fine Pd NPs, together with the intrinsic properties of 2D MXene, the obtained Pd-MXene showed a specific surface area of 97.5 m2g−1 and multiple pore channels that enabled excellent electrocatalytic activity for the reduction of CO2. Further, the 2D Pd-MXene hybrid nanocatalyst enables selective electroreduction of CO2 into selective production of CH3OH in ambient conditions by multiple electron transfer. A detailed explanation of the CO2RR mechanism is presented, and the faradic efficiency (FE) of CH3OH is tuned by varying the cell potential. Recyclability studies were conducted to demonstrate the practical application of CO2 reduction into selective production of CH3OH. In this study, metal and MXene interfaces were created to achieve a highly selective electroreduction of CO2 into fuels and other value-added chemical products.

Theoretical Study of Electrocatalytic CO2 Reduction Mechanism on Typical MXenes under Realistic Conditions

“…34 In addition, bicarbonates as electrolyte is commonly used in electrocatalytic CO 2 RR. [23][24][25][26][27]35 The elucidation of pH, electrode potential, and electrolyte influence on the surface structure is paramount. In a thermodynamic context, the Pourbaix diagram serves as a powerful tool, delineating equilibrium surface structures across varying pH and applied potentials, thus facilitating the determination of active phases under diverse thermodynamic conditions.…”

“…Strongin et al conducted electrocatalytic CO 2 RR on Mo 2 C and Ti 3 C 2 to make CO effectively . In recent reports, MXenes with various modifications had been exploited in electrocatalytic CO 2 RR with plausible performance. − These pioneer studies about CO 2 RR on MXenes demonstrated the predicted promising capability of MXenes for CO 2 RR.…”

“…However, in electrocatalysis, reactions are usually carried out in solution of given pH with various electrode potential . In addition, bicarbonates as electrolyte is commonly used in electrocatalytic CO 2 RR. − , The elucidation of pH, electrode potential, and electrolyte influence on the surface structure is paramount. In a thermodynamic context, the Pourbaix diagram serves as a powerful tool, delineating equilibrium surface structures across varying pH and applied potentials, thus facilitating the determination of active phases under diverse thermodynamic conditions. , This methodology has proven effective in identifying active phases for OER and HER on transition metals and their oxides in electrocatalytic scenarios. − Prevailing theoretical discussions on the mechanism of the CO 2 RR on MXenes primarily focus on MXene surfaces without considering such crucial conditions.…”

Synergistic Bimetallic Sites in 2D-on-2D Heterostructures for Enhanced C–N Coupling in Sustainable Urea Synthesis

“…However, pure Pd leads to a higher cost when considering its in commercial applications . Our previous studies demonstrate that the alloy formation of Ru–Pd is highly electroactive in the electrocatalysis application which make them in cost-effective Ru–Pd/WO 3 /MXene electrocatalyst for the adsorption and conversion of N 2 and CO 2 into urea. , Here, the fabrication of a Ru–Pd/WO 3 /MXene electrocatalyst was attempted to evaluate N 2 CO 2 RR in urea production. Electrocatalytic N 2 CO 2 RR uniquely requires hydrogen species at the cathode for effective urea conversion.…”

Ti3C2@g-C3N4/TiO2 Ternary Heterogeneous Photocatalyst for Promoted Photocatalytic Degradation Activities

“…2 of 16 Ti 3 C 2 , the most common MXene, possesses a two-dimensional graphene-like structure, leading to its capabilities such as excellent light absorption, electrical conductivity and good hydrophilicity [42][43][44]. Thus, it has been used as a cocatalyst for photocatalysis reactions.…”