OICC Press Journal of Nanostructure in Chemistry 2193-8865 14 5 2023 01 03 One-step construction of Co(OH)2-anchored g-C3N4 and rGO with phase junction for dopamine sensing and oxygen evolution reaction 10.1007/s40097-022-00521-1 EN Dexin Yu Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Harbin Normal University, Harbin, 150025, CN Feng Zhang Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Harbin Normal University, Harbin, 150025, CN Key Laboratory of Photonic and Electronic Bandgap Materials, Ministry of Education, Harbin Normal University, Harbin, 150025, CN Kai Yu Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Harbin Normal University, Harbin, 150025, CN Key Laboratory of Photonic and Electronic Bandgap Materials, Ministry of Education, Harbin Normal University, Harbin, 150025, CN Fengyu Qu Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Harbin Normal University, Harbin, 150025, CN Key Laboratory of Photonic and Electronic Bandgap Materials, Ministry of Education, Harbin Normal University, Harbin, 150025, CN Journal Article 2023 01 03 Abstract Cobalt-based Layered double hydroxides (Co-LDHs) through designing composite nanostructures and heterogenous junctions, has absorbed an increased concern for dual-function applications including electrochemical sensing and energy devices. Herein, the g-C 3 N 4 and GO are applied as two-dimensional (2D) scaffolds for one-pot synthesis of 2D α/β-Co(OH) 2 phase junction (α/β-Co(OH) 2 /g–C 3 N 4 /rGO, denoted as CCG) in dopamine sensing and oxygen evolution reaction (OER). The coexist of hetero-phase structure (α and β-Co(OH) 2 ) toward crystalline phase has been confirmed by various techniques. Dependent on hetero-phase structural and compositional characteristics of CCG, CCG has revealed excellent electrochemical performance: a ranking sensing response to dopamine with ppb-level sensitivity and wide detection range; and high electrocatalytic ability (38.02 mV dec −1 ) with more stable catalytic capacity toward oxygen evolution reaction (OER). The above considerable potentials for CCG ascribes to the synergistic effect of heterostructure, phase structure along with defect of α/β-Co(OH) 2 .