Anion engineering guided MOF-to-hollow nickel phosphate transformation enabling robust electrochemical platforms for detection of hydrogen peroxide and hydrazine

Abstract

Rationally designing of transition metal phosphate (TMP) with charming structure and exploiting their electroanalytic functionalities are of great potential and challenging. Herein, in-situ adoption of MOF as the framework and skillfully regulation of the evolution process through the mass ratios of sodium phosphate (namely as both etchants and reactants) and Ni-MOFs led to the configuration of a series of nickel phosphate (NiP) counterparts with well-defined structures and definable compositions, and further their bifunctional sensing performance for H2O2 and N2H4 were investigated, where the ratio of 4:3 prepared NiP, with pure ingredient, amorphous states and 2D scaly nanosheets uniformly decorated 3D hollow scaffolds, collectively reveals rich electrocatalytic sites, shorten ion transfer/diffusion channels and excellent electrical conductivity, thus affording an significant enhancement for its electrochemical behaviors, especially its low detection limit (27.9 nM and 45.1 nM) and wide measurable range (0.001–2.6 mM and 0.005–4.5 mM) for H2O2 and N2H4, respectively. Additionally, its powerful anti-interference and recognition for H2O2 and N2H4 in water samples verify the practicality of our electrochemical platforms. Our design establishes the promising strategy for engineering of new class MOF-derived diversified functionally materials for electroanalytical application and beyond.