## 2 Materials and Methods
### CuFeNPs@TWM Physicochemical Characterization  
The binary catalyst and its components were analyzed using various analytical techniques to gather detailed information on their morphology, structure, chemical composition, and particle size. X-ray diffraction (XRD) was employed to study the crystallinity of the catalysts, using a Bragg-Brentano powder diffractometer (PANalytical, Almelo, The Netherlands, model X'Pert PRO MPD \(\theta\)/\(\theta\)) equipped with a Co/K\(\alpha\) radiation source (AK\(\alpha\) = 1.7903 A; AK\(\alpha_{1}\) = 1.7890 A, AK\(\alpha_{2}\) = 1.7929 A) operating at 40 kV and 45 mA. The average crystalline size was determined using the Scherrer method [44] based on the data obtained by XRD analysis. The surface composition and chemical state of the elements in the material were investigated using X-ray photoelectron spectroscopy (XPS) with an ESFOSCAN instrument based on the PHI 5000 VersaProbe from Physical Electronics (ULVAC-PHI), Chanhassen, MN, USA. Measurements were conducted with a monochromatic, focused X-ray source (Al/K\(\alpha\) line: 1486.6 eV), calibrated using the Ag 3d\({}_{5/2}\) line (full width at half maximum of 0.6 eV). The analyzed area was a 100 \(\upmu\)m diameter circle. The spectral resolution was set to 224 eV Pass Energy and 0.8 eV/step for the survey spectra and 27 eV Pass Energy and 0.1 eV/step for high-resolution spectra. All measurements were performed in an ultrahigh vacuum (UHV) chamber, maintaining pressures between 5 \(\times\) 10\({}^{-10}\) and 5 \(\times\) 10\({}^{-9}\) Torr. Raman spectroscopy was performed using a Renishaw Raman spectrometer (Wotton-under-Edge, UK) with a 532 nm green laser. Surface composition was assessed through X-ray photoelectron spectroscopy (XPS) using a specific equipment model. Fourier-transform infrared spectroscopy (FT-IR) on a Nicolet iS5 Thermo Scientific (Waltham, MA, USA) system was used to identify functional groups present in the catalyst. The morphology of CuFe@TWM was examined using scanning electron microscopy (SEM) with a GeminiSEM 360 Zeiss FESEM (Oberkochen, Germany), operated under high vacuum conditions and coupled with an Ultim Max 40 Oxford energy-dispersive spectroscopy (SEM-EDS) detector (High Wycombe, UK). The magnetization properties of the catalyst were investigated at room temperature using a homemade magnetometer (Santiago, Chile). Finally, the specific surface area was determined by the Brunauer-Emmett-Teller (BET) method, using the Rouquerol criteria. For this purpose, N\({}_{2}\) adsorption/desorption isotherms at 77 K were performed in a 3 Flex Micromerities instrument (Norcross, GA, USA). The total pore volume was determined for all materials at p/p\({}_{0}\) = 0.99.  
The point of zero charge (pH\({}_{\text{p}ac}\)) of the catalyst was determined by the pH drift method [45]. For this purpose, 0.1 mol L\({}^{-1}\) of Na\({}_{2}\)SO\({}_{4}\) solution was used as an inert electrolyte. The pH was studied in the range of 1-9 and measured using a digital pH meter (Thermo Fisher Scientific, Waltham, MA, USA; model Stara 3215 Orion). The pH of the series of 20 mL of the electrolyte solution was adjusted using 0.1 mol L\({}^{-1}\) of H\({}_{2}\)SO\({}_{4}\)/NaOH solutions. These pH values were labeled as initial pH (pH\({}_{\text{i}}\)). Catalyst loads (4 mg) were added to the different solutions in stoppered glass tubes and equilibrated for 24 h. After this, the final pH (pH\({}_{\text{f}}\)) was measured and plotted against the pH\({}_{\text{i}}\). The pHpzc was taken when the pH crossed the line pH\({}_{\text{i}}\) = pH\({}_{\text{f}}\).