Aluminum MOF-based sensor for simultaneous colorimetric and fluorometric detection of Co+2 in electroplating wastewater samples and recovery of Pd+2 ions from electronic wastes

The study aimed to develop an innovative Aluminum-based sensitive sensor material, HPDTP-Al MOF sensor. The sensor was meticulously crafted through the diazotization of the NH2-MIL53(Al) MOF and coupling it with resorcinol to develop the HPDTP-Al MOF sensor material. The performance, selectivity, and sensitivity of the developed HPDTP-Al MOF were thoroughly evaluated. It successfully detected ultra-trace concentrations of Co2+ and Pd2+ ions using spectrophotometric and fluorometric methods. The MOF was tested by detecting and removing Co2+ in real electroplating wastewater samples. It was also used to recover Pd2+ ions from electronic wastes. To comprehensively characterize the HPDTP-Al MOF sensor material, a range of techniques involving TEM, XRD, BET, SEM, and XPS were employed. These methods not only confirmed the successful synthesis of the sensor material, but also provided valuable insights into its surface and structural properties. The optimization process involved fine-tuning the conditions for Co2+ and Pd2+ ions detection using both colorimetric and fluorometric approaches. Impressively, the sensor material exhibited swift detection capabilities, achieving a stable spectroscopic signal in under 1 min. Furthermore, the study delved into the sensor material's recyclability, which exhibited promising results, enabling its efficient reuse for up to 6 cycles. The exploitation of 0.1 M HCl and 0.1 Citrate as an eluent for the regeneration of the sensor material. The sensor's real-world potential was assessed through the analysis of diverse sample types, including electroplating wastewater for the removal and detection of Co2+ ions and the recovery of valuable Pd2+ ions from electronic wastes. These findings unequivocally emphasize the sensor material's promise for practical applications in various real-world scenarios, especially as environmental solutions.