LAUSR

Constructing pH stimuli-responsive smart material provides new opportunity to address the problem that traditional electrocatalysts cannot achieve both alkaline oxygen evolution reaction (OER) and acidic hydrogen evolution reaction (HER) activities. Herein, the amphoteric conjugated ligand (BDC-NH2) modified 3d-block metal-anchored graphitic carbon nitride (3d metal-C3N4) smart electrocatalysts are constructed, and self-adaptation of electronic structure is realized by self-response of pH-stimulation, so as to achieve self-adjustment of alkaline OER and acidic HER. Specifically, the amino and carboxyl functional groups in BDC-NH2 undergo protonation and deprotonation respectively under different pH stimulation to adapt to environmental changes, while combined with the DFT calculation, the increase or decrease of electron delocalization range brought by the self-response characteristic will lead to redistribution of the Bader charge around the modified active sites. As an excellent paradigm, the OER and HER activities can be greatly promoted by ~ 4.8 and ~ 8.5 times over Co-C3N4 after BDC-NH2 induced self-adaptive processes under different environments, arising from the reduced energy barrier of O* to OOH* and ΔGH*. Impressively, the proposed BDC-NH2-induced smart regulation strategy is applicable to a series of 3d metal-C3N4, including Co, Ni and Fe, providing a general structural upgrading scheme for constructing smart electrocatalytic systems.