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[Display omitted] In the process of photocatalytic ammonia synthesis, efficient activation of nitrogen molecules constitutes a fundamental challenge. During the N 2 activation, the close interdependence between the acceptance and donation of electron results in their mutual limitation, leading to high energy barrier for N 2 activation and unsatisfactory photocatalytic performance. This work decoupled the electron acceptance and donation processes by constructing Fe-Bi dual active sites, resulting in enhancing N 2 activation through the high electron trapping ability of Fe3+ and strong electron donating ability of Bi2+. The photocatalytic nitrogen reduction efficiency of 3%Fe/Bi 2 O 2.33 (118.71 μmol g cat −1h−1) is 5.3 times that of Bi 2 O 2.33 (22.41 μmol g cat −1h−1). In-situ Fourier transform infrared (In situ FTIR) spectroscopy and density functional theory (DFT) calculations manifest that Fe3+-Bi2+ dual active sites work together to promote nitrogen adsorption and activation, and the reaction path is more inclined toward alternate hydrogenation path. N 2 adsorption and activation properties are optimized by heteronuclear bimetallic active sites, which offers a new way for the rational design of nitrogen-fixing photocatalysts. [ABSTRACT FROM AUTHOR]

Producing hydrogen from organic/inorganic hydrides is an innovative clean energy alternative to fossil fuels, addressing the increasing energy demands. Here, we first propose coupled photocatalytic water hydrogen production and N,N-dimethylformamide (DMF, C 3 H 7 NO) dehydrogenation technology to obtain high value-added H 2 and N,N-dimethylcarbamic acid (C 3 H 7 NO 2). ZnIn 2 S 4 @MIL-125(Ti) nanoheterostructures were synthesized using a simple solvothermal method and resulting in a photocatalytic H 2 production rate of 2.135 mmol h−1 g−1 (apparent quantum efficiency at 380 nm was 2.6 %) which is 2.77 times higher than pure ZnIn 2 S 4. Liquid-phase mass spectrometry indicates that the DMF oxidation activity of ZIS@MIL heterojunction is double pure ZnIn 2 S 4 and only microcrystalline CO 2 is produced. Isotopes indicate that the production pathway of H 2 results from the coupling of the –CHO bond in DMF and the –H in water. The improved photocatalytic activity of the ZnIn 2 S 4 @MIL-125(Ti) heterostructure is attributed to facilitating efficient charge carrier transfer and separation and DMF depletion of holes accelerates electron transfer. The ZnIn 2 S 4 @MIL-125(Ti) heterojunction was synthesized to enhance the rate of photo-induced charge carrier separation, facilitating the efficient decomposition of dimethylformamide (DMF) for hydrogen production and the generation of valuable intermediate product C 3 H 7 NO 2. [Display omitted] • The ZnIn 2 S 4 @MIL-125(Ti) heterojunction is successfully prepared by two-step hydrothermal method. • The hydrogen production experiment of a new sacrificial agent (DMF). • The photocatalytic products of DMF are analyzed. • The exploration of hydrogen production mechanism are analyzed. [ABSTRACT FROM AUTHOR]