Boosting CO₂ Electroreduction via the Synergistic Effect of Tuning Cationic Clusters and Visible‐Light Irradiation

Abstract

Introducing an external light field can increase the intrinsic activity and energy efficiency for electrochemical CO2 reduction. Herein, a synergistic strategy that introduces photosensitive components and visible light into a stable system is reported to improve the performance for CO2 reduction. The catalytic kinetics studies indicate that the synergistic effect of implantation of cationic Ti and additional light driving is the primary responsibility for accelerating the first electron transfer to form a *COO− intermediate. This leads to a satisfactory CO2‐to‐CO conversion for Zr/Ti‐NB‐Co in terms of high selectivity (Faradaic efficiency of 93.6% at −0.7 V), remarkable catalytic activity (production rate up to 546 mmol g−1 h−1 at −1.1 V), excellent long‐term stability (without performance decay over 11 h), and large turnover frequency of 1028 h−1 at −1.1 V under visible light. These results imply that the photodriven Ti‐based porphyrin catalyst not only can deliver more electrons, but also can act as a photoswitch to adjust the electron transfer pathway.

Design strategies for markedly enhancing energy efficiency in the electrocatalytic CO2 reduction reaction

“…In addition, the optical field has shown to be effective to control the electrochemical water splitting, and similar exploration in the CO 2 RR area is emerging and will be meaningful as well to promote the conversion efficiency of CO 2 . 147,148 4. Integrated electrolysis: a promising route to boosting energy efficiency and economic benefit of CO 2 electrolysis…”

2D π‐conjugated metal–organic frameworks for CO2 electroreduction

“…(M) Stability test of Zr/Ti‐NB‐Co MOF at −0.7 V under visible light. Reproduced with permission: Copyright 2021, Wiley 70 . MOF, metal–organic framework; SEM, scanning electron microscope; STEM, scanning transmission electron microscope; TEM, transmission electron microscope…”

“…To further understand the role of external light field in the intrinsic activity and energy efficiency for CO 2 RR, another case reported the fabrication of a stable and efficient Zr/Ti‐NB‐Co MOF catalyst via implantation of cationic Ti into the cluster of Zr‐NC‐Co MOF (Figure 3E) by Wang et al 70 Thus, Zr/Ti‐NB‐Co MOF was composed of Zr 3.2 Ti 2.8 clusters and porphyrin ligands. As shown in Figure 3F–I, a hierarchical hollow structure was exhibited.…”

Heterogenization of Molecular Electrocatalytic Active Sites through Reticular Chemistry

“…[59] www.advmat.de www.advancedsciencenews.com composed of Zr 6 (µ 3 -O) 4 (µ 3 -OH) 4 SBUs and CoTCPP linkers. [48] Zr/Ti-NB-Co was synthesized by a cation exchange process, converting Zr 6 SBUs of PCN-224 to Zr 3.2 Ti 2.8 . The photo-active properties of the cationic Ti accelerated the initial electron transfer leading to the formation of *COO − .…”