Hierarchically Converged Defect Engineering with 2-Dimensional Black Phosphorus/MXene Sequence for Sensitive Photoelectrochemical-Electrostatic Sensors
Wei Zeng, Yuan Zhang, Zhengyin Wu, Zichu Zhang, Liting Deng, Yuan Tian, Mengying Che, Yi‐Ming Chen, Yi Xiong, Yumin Wang, Pengfei Fang, Yun Tang, Shuoxue Jin, Suiting Ning
Abstract
The function-integrated sensors have harvested increasingly vital across diverse applications, especially in the field of smart wearables, yet optimizing the synergy between electrostatic and light signals in photoelectrochemical (PEC) systems remains a critical challenge. Here, we fabricate a hierarchical ZnO/Bi 2 O 3 /BiOCl/black phosphorus (BP)/MXene (Ti 3 C 2 T x ) heterostructure and develop a PEC sensor tailored for electrostatic coupling and surface electromyography (sEMG) detection. Sequential integration of 2-dimensional (2D) BP and Ti 3 C 2 T x precisely repairs defects in the 3D ZnO/Bi 2 O 3 /BiOCl framework, enhancing electrode contact area and forming multidimensional heterostructures that markedly boost electron–hole separation. Under illumination or ambient electrostatic field (AEF) stimulation, the composite electrode outperforms its pristine counterpart, achieving a photocurrent of 20.46 μA cm −2 under 30-W blue light, which is 2.4 times higher than the device without the 2D layers. A synergistic AEF–light effect further enhances carrier transport, amplifying AEF detection sensitivity. These results highlight defect engineering as a robust strategy for advancing PEC performance in PEC applications and enable a light-assisted sEMG sensor with marked signal improvement.