Fe-Bi dual sites regulation of Bi2O2.33 nanosheets to promote photocatalytic nitrogen fixation activity

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 Fe 3+ and strong electron donating ability of Bi 2+ . The photocatalytic nitrogen reduction efficiency of 3%Fe/Bi 2 O 2.33 (118.71 μmol g cat −1 h −1 ) is 5.3 times that of Bi 2 O 2.33 (22.41 μmol g cat −1 h −1 ). In-situ Fourier transform infrared (In situ FTIR) spectroscopy and density functional theory (DFT) calculations manifest that Fe 3+ -Bi 2+ 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 .