A highly active nickel electrocatalyst shows excellent selectivity for CO2 reduction in acidic media Photochemical CO2 reduction in water using a co-immobilised nickel catalyst and a visible light sensitiser A functionalised nickel cyclam catalyst for CO2 reduction: electrocatalysis, semiconductor surface immobilisation and light-driven electron transfer Improving the efficiency of electrochemical CO2 reduction using immobilized manganese complexes Electrocatalytic CO2 reduction with a membrane supported manganese catalyst in aqueous solution