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It is of pivotal significance to explore robust photocatalysts to promote the photoreduction of CO2 into solar fuels. Herein, an intelligent metal‐insulator‐semiconductor (MIS) nano‐architectural photosystem was constructed by electrostatic self‐assembly between cetyltrimethylammonium bromide (CTAB) insulator‐capped metal Ni nanoparticles (NPs) and covalent triazine‐based frameworks (CTF‐1). The metal‐insulator‐CTF composites unveiled a substantially higher CO evolution rate (1254.15 μmol g−1 h−1) compared with primitive CTF‐1 (1.08 μmol g−1 h−1) and reached considerable selectivity (98.9 %) under visible‐light irradiation. The superior photocatalytic CO2 conversion activity over Ni‐CTAB‐CTF nanoarchitecture could be attributed to the larger surface area, reinforced visible‐light response, and CO2 capture capacity. More importantly, the Ni‐CTAB‐CTF nanoarchitecture endowed the photoexcited electrons on CTF‐1 with the ability to tunnel across the thin CTAB insulating layer, directionally migrating to Ni NPs and thereby leading to the efficient separation of photogenerated electrons and holes in the photosystem. In addition, isotope‐labeled (13CO2) tracer results verified that the reduction products come from CO2 rather than the decomposition of the photocatalysts. This study opens a new avenue for establishing a highly efficient and selective artificial photosystem for CO2 conversion. [ABSTRACT FROM AUTHOR]

Across Canada's boreal forest, disturbances from in situ oil sands mining, including well‐pads, significantly impact vast areas of the landscape. The creation of well‐pads requires removal of vegetation and placement of mineral fill, which essentially stops any carbon (C) sequestration on the once peatland ecosystem. It is important that, once no longer in use, these well‐pads are restored as long‐term C (peat) accumulation is what defines peatland ecosystem. However, little is known about the recovery of greenhouse gas exchange post‐restoration of these features. We studied a decommissioned well‐pad located in a treed poor fen that was restored using three soil adjustment treatments (SATs): (1) complete mineral fill removal (Peat‐Dec); (2) partial pad removal and burial under peat layer (BUPL); and (3) mixing mineral and peat by inversion (Mixed‐P‐M). The recreated peat surface was revegetated with donor peatland species using the moss layer transfer technique (MLTT). The objectives of this paper were to (1) quantify plot‐scale seasonal carbon dioxide (CO2) and methane (CH4) exchange of the SATs, 2–4 years post‐restoration compared to reference sites and (2) determine the influence of several environmental variables on CO2 and CH4 exchange. All SATs proved effective in recreating a soil surface needed to support peatland vegetation as shown by similar rates of net ecosystem exchange (NEE). Equally, both types of vegetation reintroduced led this site on a trajectory toward functioning as a net C sink. [ABSTRACT FROM AUTHOR]