A robust and efficient cobalt molecular catalyst for CO₂ reduction

Abstract

Visible-light driven CO2 reduction is considered to be a sustainable energy source. However, earth-abundant molecular catalysts with high efficiency and robustness towards solar-driven CO2 reduction are limited. Herein, we report a cobalt complex supported by a tetradentate tripodal ligand, which demonstrates catalytic solar-driven CO2 reduction with TON(CO) > 900 over 70 h in the presence of a photosensitizer.

Highly Efficient and Selective Visible‐Light Driven CO2‐to‐CO Conversion by a Co(II) Homogeneous Catalyst in H2O/CH3CN Solution

“…For instance, Chan et al. reported [Co II (TPA)Cl]Cl (TPA=tris(2‐pyridylmethyl)amine) as a catalyst for photocatalytic CO 2 ‐to‐CO conversion in dry acetonitrile with a TON CO of 953 and a selectivity of 85 % . Among tripodal ligands, we are particularly interested in the tris‐(2‐aminoethyl)amine (tren) derivatives for their strong chelating ability.…”

Artificial Photosynthetic Systems for CO2 Reduction: Progress on Higher Efficiency with Cobalt Complexes as Catalysts

“…1, entry 16). [25,51] ATON and as electivity of 953 and 85 %w ere achieved after 70 hours of irradiation. By using the more stable and emissive PS P6 (Figure 2), Che and co-workerso btained aT ON of > 2400 and as electivity of 95 % for CO production by C14 (Table 1, entry 17).…”

“…[14][15][16][17][18][19][20][21][22][23][24] These systems realized CO 2 -to-CO and/or CO 2 -to-formate conversion successfully under light irradiation. Recently,awidev ariety of novel cobaltc omplexes have been reported for photocatalytic CO 2 reduction, [25][26][27][28][29][30][31] exhibitingi mpressive activitiesa nd selectivities. Moreover,s omep reviously reportedm olecular cobalt catalysts have also been used to fabricate hybridc atalysts or photoelectrodes for heterogeneous photocatalytic or photoelectro-chemicalCO 2 reduction.…”

Titelbild: A Dinuclear Cobalt Cryptate as a Homogeneous Photocatalyst for Highly Selective and Efficient Visible‐Light Driven CO2 Reduction to CO in CH3CN/H2O Solution (Angew. Chem. 3/2017)

“…In recent years,considerable efforts have been devoted to the development of molecular photocatalysts,with the aim of high efficiency and selectivity of CO 2 reduction, of which getting as ingle reduction production of CO has been attracted particular attention. [10] An umber of molecular photocatalysts that could catalyze the reduction of CO 2 to CO driven by visible-light have been reported, including Re, [11] Ru, [12] Ir, [13] Co, [14] Ni, [15] Mn, [16] Fe. [17] Although great progress has been achieved, the solar-driven reduction of CO 2 to CO is still al ongstanding challenge,a sm ost of the reported molecular photocatalysts for CO 2 -to-CO conversion display low efficiency,w ith low TONa nd TOF values of approximately 10 À1 -10 3 and approximately 10 À5 -10 À1 s À1 ,r espectively.…”

“…[15] More importantly,t he high selectivity and efficiency of 1 for CO 2 -to-CO conversion are achieved in 4:1C H 3 CN/ H 2 O(v/v)solution, awater-containing reaction system where almost all the reported molecular catalysts display low efficiency and selectivity for the photo-reduction of CO 2 to CO in such reaction system. [14,15] Undoubtedly,t he high selectivity and efficiency of 1 towards the CO 2 reduction in aw ater containing reaction system will vastly extend the practical applications for CO 2 reduction in combined with aw ater oxidation to achieve ac arbon neutral artificial photosynthesis cycle.…”