Molecular-level　understanding　of　the　solar-driven　CO2　conversion　is　of　importance　to　design　high-efficiency　artificial　photosynthetic　systems　for　rebalancing　the　global　carbon　cycle.　Herein,　some　physical　insights　into　the　surface　plasmon　resonance　(SPR)　mediated　CO2　photoreduction　were　demonstrated　with　metal　(Au,　Ag,　and　Pd)/3D　porous　ZnO　nanosheets　(NSs).　Such　plasmonic　photocatalysts　were　designed　elaborately　to　expose　the　polar　{001}　facet,　based　on　the　physical　prototype　of　field-field　coupling,　in　order　to　benefit　chemical　polarization　and　activation　of　the　inert　molecule.　Among　these　plasmonic　metals,　gold　was　found　to　be　not　only　more　effective　for　promoting　the　solar-driven　CO2　conversion,　but　unique　for　producing　the　higher　hydrocarbon,　C2H6.　A　10-fold　enhanced　conversion　efficiency　and　a　quantum　efficiency　of　1.03%　were　achieved　on　Au/ZnO　NSs　at　ca.　80%　selectivity　to　hydrocarbons　under　solar　light　irradiation.　The　characterization　results　indicated　that　the　metal-semiconductor　interaction　enables　the　electron-phonon　decoupling　to　generate　more　amounts　of　energetic　electrons　in　the　excited　ZnO　NSs　by　a　proposed　pathway,　called　the　SPR　energy　transfer　induced　interband　transition　that　promotes　the　semiconductor　photoexcitation,　kinetically　accelerating　the　conversion.　Density　functional　theory　calculations　revealed　that　the　field-field　coupling　greatly　intensifies　the　surface　polarization　for　adsorbates,　charging　negatively　the　C　atom　of　CO2　and　making　O=C=O　bond　bent,　along　with　the　electrophilic　attack　by　two　competitive　paths,　leading　to　the　concomitance　of　CO　and　CH4.　The　loading　of　plasmonic　metal　nanoparticles　alters　the　molecular　paths　of　CO2　conversion　by　tuning　thermodynamically　the　first　dehydroxylation　step,　consequently　the　product　selectivity.　Especially　Au　plasmon,　it　enables　the　CO　hydrogenation　path,　making　CH4　faster.