In:
Journal of Materials Chemistry A, Royal Society of Chemistry (RSC), Vol. 10, No. 4 ( 2022), p. 1965-1975
Abstract:
Ti 3 C 2 T x MXene nanostructures have garnered attention for various catalytic applications due to their built-in electronic properties. Herein, we rationally design highly exfoliated two-dimensional Ti 3 C 2 T x nanosheets (T x = O, OH, and F) doped with Cu (denoted as Cu/Ti 3 C 2 T x ) for the electrochemical CO 2 reduction reaction (CO 2 RR). The fabrication process entails the selective chemical etching of Ti 3 AlC 2 followed by the delamination thereof under ultrasonic treatment and subsequent mixing with a Cu precursor to allow in situ doping. The resultant Cu/Ti 3 C 2 T x are highly exfoliated nanosheets with a surface area of 46 m 2 g −1 and are uniformly doped with Cu atoms (1.04 wt%). The CO 2 RR current density of Cu/Ti 3 C 2 T x (−1.08 mA cm −2 ) was 3.6 times higher than that of Ti 3 C 2 T x (−0.3 mA cm −2 ) besides a lower onset reduction potential and Tafel slope, and higher stability, due to the greater surface area, electronic effect, and quicker charge transfer on Cu/Ti 3 C 2 T x . The formic acid (HCOOH) faradaic efficiency on Cu/Ti 3 C 2 T x (58.1%) was 3-fold higher than that on Ti 3 C 2 T x (18.7%). Based on density functional theory (DFT) simulation, Cu-doping induces polarized sites with high electron density, allowing the CO 2 RR path through the *HCOOH intermediate to form formic acid (HCOOH). The study presented here will open new pathways for using Ti 3 C 2 T x doped with various metals for the CO 2 RR.
Type of Medium:
Online Resource
ISSN:
2050-7488
,
2050-7496
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2022
detail.hit.zdb_id:
2702232-8
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