Photochemical In Situ Exfoliation of Metal–Organic Frameworks for Enhanced Visible‐Light‐Driven CO₂ Reduction

Abstract

Two novel two‐dimensional metal–organic frameworks (2D MOFs), 2D‐M2TCPE (M=Co or Ni, TCPE=1,1,2,2‐tetra(4‐carboxylphenyl)ethylene), which are composed of staggered (4,4)‐grid layers based on paddlewheel‐shaped dimers, serve as heterogeneous photocatalysts for efficient reduction of CO2 to CO. During the visible‐light‐driven catalysis, these structures undergo in situ exfoliation to form nanosheets, which exhibit excellent stability and improved catalytic activity. The exfoliated 2D‐M2TCPE nanosheets display a high CO evolution rate of 4174 μmol g−1 h−1 and high selectivity of 97.3 % for M=Co and Ni, and thus are superior to most reported MOFs. The performance differences and photocatalytic mechanisms have been studied with theoretical calculations and photoelectric experiments. This study provides new insight for the controllable synthesis of effective crystalline photocatalysts based on structural and morphological coregulation.

Facile electron delivery from graphene template to ultrathin metal-organic layers for boosting CO2 photoreduction

“…34 times higher than that of bulky Co-MOF under similar condition, indicative of the remarkable intrinsic catalytic activity of ultrathin Co-MOF in Co-MOL@GO. Impressively, in terms of CO yield and selectivity, the catalytic performance of Co-MOL@GO (3133 mmol g MOL –1 , 95%) is comparable to most state-of-the-art MOF catalysts for visible-light-driven CO 2 reduction, such as 2D-Ni 2 TCPE 37 (20 mmol g –1 , 97%, TON 13.9), Ni MOLs 21 (25 mmol g –1 , 98%, TON 8), MAF-X27l-OH 10 (25.4 mmol g –1 , 98%, TON 2124), Co-ZIF-9 13 (209 mmol g –1 , 58%, TON 89.6), Ni(TPA/TEG) 38 (47 mmol g –1 , 99%, TON 11.5), and other examples listed in Supplementary Table 3 . We further scaled up the reactor by five times to minimize the measurement error and get closer to realistic applications (see Methods and Supplementary Fig.…”

Robust Biological Hydrogen‐Bonded Organic Framework with Post‐Functionalized Rhenium(I) Sites for Efficient Heterogeneous Visible‐Light‐Driven CO2 Reduction

“…In particular for CO evolution rate,i tw as enhanced 51 times in comparison with that (28 mmol g À1 h À1 )i nt he absence of photosensitizer due to the introduction of electron transfer from [Ru-(bpy) 3 ]Cl 2 to HOF-25-Re. [15,18] In the control experiment by reducing the amount of HOF-25-Re (2.0 mg), the highly selective photocatalytic performance,i nt erm of the CO evolution rates of 3030 mmol g À1 h À1 ,i sm uch superior to that of photocatalyst (5.0 mg) ( Table 1). Such ar apid CO evolution rate and high product selectivity of 93 %o bviously surpass those excellent photocatalysts such as Ni-TpBpy, [4a] MAF-X27-OH, [19] and MOF-Co [20] under the help of [Ru-(bpy) 3 ]Cl 2 •6 H 2 Op hotosensitizer (Table 1).…”

Acid–base resistant ligand-modified molybdenum–sulfur clusters with enhanced photocatalytic activity towards hydrogen evolution

“…5a, the PL intensity of [Ru(bpy) 3 ]Cl 2 gradually decreased as the amount of MoS-MBTZ increased, and followed a linear Stern-Volmer behavior, indicating that the photogenerated electrons can be transferred from the excited state of [Ru(bpy) 3 ]Cl 2 to MoS-MBTZ. 53,54 In contrast, the PL emission was not quenched signicantly by increasing the amount of TEOA, which indirectly conrmed that the excited state of [Ru(bpy) 3 ]Cl 2 is quenched by MoS-MBTZ (Fig. S20 †).…”