Enhanced electrochemical activity by MOF superstructure derived Ni₂P@C for ultrasensitive sensing of Bisphenol A

Electrochemical (EC) sensing of bisphenol A (BPA), a notorious persistent contaminant, is of pressing interest. However, the state-of-the-art BPA sensors are challenged by two performance parameters: limited EC catalysis and sensitivity. Herein, a two-dimensional (2D) metal-organic framework (MOF) superstructure-derived Ni₂P@C probe elicits a novel EC sensor that exhibits high-efficiency BPA detection. Thanks to the abundant Ni^δ+ active sites exposed uniformly on cross-linked layers stemming from the inherited 2D-MOF superstructures as the precursors, high conductivity results from the organic linkers-derived graphitic carbon. The prepared Ni₂P@C composites-based EC sensors demonstrated exceptional BPA-induced sensing responses with a wide dynamic response range, high sensitivity of 0.951 μA cm⁻²·μM⁻¹, a low limit of detection (LOD, 56.8 nM) in the linear range of 1 μM–100 μM. Below 1 μM, the response followed the logarithm of BPA concentrations, indicating the potential for detection down to 5 pM. The excellent selectivity in the presence of similar interferents, combined with high reproducibility and chemical stability, underscores the potential of 2D MOF-derived Ni₂P@C for accurate monitoring of hazardous phenols, opening new avenues for environmental sensing and remediation.