@article{scholars18746,
            year = {2023},
         journal = {Chemosensors},
          number = {3},
            note = {cited By 0},
          volume = {11},
           title = {Facile Electrochemical Approach Based on Hydrogen-Bonded MOFs-Derived Tungsten Ethoxide/Polypyrrole-Reduced GO Nanocrystal for ppb Level Ammonium Ions Detection},
             doi = {10.3390/chemosensors11030201},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85151160961&doi=10.3390\%2fchemosensors11030201&partnerID=40&md5=74f4bc5363a2227f8fb5daa8462414fc},
          author = {Mohd Hizam, S. M. and Mohamed Saheed, M. S.},
        abstract = {Ammonium (NH4+) ions are a primary contaminant in the river and along the waterside near an agricultural area, therefore, necessitating sensitive detection of pollutants before irreversibly damaging environment. Herein, a new approach of metal-organic framework-derived tungsten ethoxide/polypyrrole-reduced graphene oxide (MOFs-W(OCH2CH3)6/Ppy-rGO) electrochemical sensors are introduced. Through a simple hydrothermal process, Ppy-rGO is linked to tungsten ethoxide as an organic linker. This creates the MOFs-W(OCH2CH3)6/Ppy-rGO nanocrystal through hydrogen bonding. The synergistic combination of tungsten ethoxide and Ppy-rGO provides three-fold advantages: stabilization of Ppy-rGO for extended usage, enabling detection of analytes at ambient temperature, and availability of multiple pathways for effective detection of analytes. This is demonstrated through excellent detection of NH4+ ions over a dynamic concentration range of 0.85 to 3.35 {\^A}uM with a ppb level detection limit of 0.278 {\^A}uM (9.74 ppb) and a quantitation limit of 0.843 {\^A}uM (29.54 ppb). The increment in the concentration of NH4+ ions contributes to the increment in proton (H+) concentration. The increment in proton concentration in the solution will increase the bonding activity and thus increase the conductivity. The cyclic voltammetry curves of all concentrations of NH4+ analytes at the operating potential window between {\^a}??1.5 and 1.5 V exhibit a quasi-rectangular shape, indicating consistent electronic and ionic transport. The distinctive resistance changes of the MOFs-W(OCH2CH3)6/Ppy-rGO to various NH4+ ion concentrations and ultrasensitive detection provide an extraordinary platform for its application in the agriculture industry. {\^A}{\copyright} 2023 by the authors.}
}