Copper catalysts for photo- and electro-catalytic hydrogen production

Abstract

Square planar 1, square pyramidal 2 and trigonal bipyramidal 3 copper complexes are poor catalysts for hydrogen evolution (HER) under photocatalytic conditions, whereas 1 is, or forms, a good and enduring electrocatalyst for HER, but 2 and 3 do not.

Mono-copper far more active than analogous di-copper complex for electrocatalytic hydrogen evolution

“…In contrast to the reversible reduction event at E 1/2 = −1.39 V reported for monocopper( ii ) complex 1 , 19 which is most likely copper based (Cu 2+ /Cu + ), both copper centres in the dicopper( ii ) analogue complex 2 ·4H 2 O are significantly more readily reduced, in two overlapping reduction events, at −1.08 and −1.25 V (Fig. 3).…”

“…The solubility of [Cu II L Et ]BF 4 ( 1 ) was similar, except that it is also moderately soluble in chloroform and water. 19…”

“…3–6. 18,19 Both studies were carried out in dry MeCN with 0.1 M Bu 4 NPF 6 as the supporting electrolyte with a 0.01 M AgNO 3 /Ag reference electrode, and a glassy carbon working electrode (diameter 3 mm, A = 0.071 cm 2 ).…”

“…1), 18 was shown to have a reversible redox process at −1.39 V versus 0.01 M AgNO 3 /Ag, in dry MeCN with 0.10 M Bu 4 NPF 6 , and to have high and long lived electrocatalytic HER activity in the presence of 80 equivalents of acetic acid as the proton source ( E applied = −1.60 V for 6 hours gave TON = 12.5, but activity remained high so this is an underestimate of the true TON). 19,20…”

Synthesis, Spectroscopic, Thermal, and Catalytic Properties of Eight New Complexes of Metal(II) Formates or Propionates with Imidazole; Relationship between the Carbon Chain Length and Catalytic Activity

“…It is thus important to determine the relationship between structure and activity, which is currently one of the most promising strategies in new drugs and catalyst design. All four mentioned metals, cobalt [ 8 , 9 , 10 , 11 ], nickel [ 12 , 13 , 14 ], copper [ 15 , 16 , 17 ], and zinc [ 17 , 18 , 19 ] are crucial and widely used in catalysis. One of the important reactions, problematic from an industrial point of view, is the reaction of the oxidation of styrene.…”