The photocatalytic reduction of CO₂ to CH₄ in a hydrous solution was successfully achieved by a homogeneous molecular catalytic system involving two dinuclear nickel complex catalysts (i.e., [(dmbpy)₂Ni₂Cl₄(H₂O)₂] (1) (dmbpy = 4,4′-dimethyl-2,2′-bipyridine) and [(bpy)₂Ni₂Cl₄(H₂O)₂] (2) (bpy = 2,2′-bipyridine)), in the presence of [Ru(bpy)₃²⁺] or organic dye such as Eosin Y as a photosensitizer. Control and cyclic voltammetry experiments (CV) revealed that H₂O could provide the H⁺ required for the conversion of CO₂ into CH₄ and ruled out CO as an intermediate in this reaction.

中文翻译：

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双核镍催化剂在含水溶液中由CO ₂形成可见光驱动的甲烷

通过包含两种双核镍配合物催化剂（即[[dmbpy）₂ Ni ₂ Cl ₄（H ₂ O）₂ ]（1）的均相分子催化体系，成功实现了在水溶液中将CO ₂光催化还原为CH ₄。（dmbpy = 4,4'-二甲基-2,2'-联吡啶）和[（bpy）₂ Ni ₂ Cl ₄（H ₂ O）₂ ]（2）（bpy = 2,2'-联吡啶）），在[Ru（bpy）₃ ²⁺ ]或有机染料如曙红Y作为光敏剂的存在。对照和循环伏安法实验（CV）显示H ₂O可以提供将CO ₂转化为CH ₄所需的H ⁺，从而排除了CO作为该反应的中间体。