Pt,Pd,Ni/MgO, Pt,Pd,Ni/Mg_0.97La³⁺_0.03O, Pt,Pd,Ni/Mg_0.93La³⁺_0.07O, and Pt,Pd,Ni/Mg_0.85La³⁺_0.15O (1% of each of the Ni, Pd, and Pt) catalysts were prepared by a surfactant-assisted co-precipitation method. Samples were characterized by the XRD, XPS, XRF, FT-IR, H₂-TPR, TEM, the Brunauer–Emmett–Teller (BET) method, and TGA and were tested for the dry reforming of methane (DRM). TEM and thermal gravimetric analysis (TGA) methods were used to analyze the carbon deposition on spent catalysts after 200 h at 900 °C. At a temperature of 900 °C and a 1:1 CH₄:CO₂ ratio, the tri-metallic Pt,Pd,Ni/Mg_0.85La³⁺_0.15O catalyst with a lanthanum promoter showed a higher conversion of CH₄ (85.01%) and CO₂ (98.97%) compared to the Ni,Pd,Pt/MgO catalysts in the whole temperature range. The selectivity of H₂/CO decreased in the following order: Pt,Pd,Ni/Mg_0.85La³⁺_0.15O > Pt,Pd,Ni/Mg_0.93La³⁺_0.07O > Pt,Pd,Ni/Mg_0.97La³⁺_0.03O > Ni,Pd,Pt/MgO. The results indicated that among the catalysts, the Pt,Pd,Ni/Mg_0.85La₂³⁺_0.15O catalyst exhibited the highest activity, making it the most suitable for the dry reforming of methane reaction.

Catalysts Ni/Mg_1−xCe_x⁴⁺O and Ni,Pd,Pt/Mg_1−xCe_x⁴⁺O were developed using the co-precipitation–impregnation methods. Catalyst characterization took place using XRD, H₂-TPR, XRF, XPS, Brunauer–Emmett–Teller (BET), TGA TEM, and FE-SEM. Testing the catalysts for the dry reforming of CH₄ took place at temperatures of 700–900 °C. Findings from this study revealed a higher CH₄ and CO₂ conversion using the tri-metallic Ni,Pd,Pt/Mg_1−xCe_x⁴⁺O catalyst in comparison with Ni monometallic systems in the whole temperature ranges. The catalyst Ni,Pd,Pt/Mg_0.85Ce⁴⁺_0.15O also reported an elevated activity level (CH₄; 78%, and CO₂; 90%) and an outstanding stability. Carbon deposition on spent catalysts was analyzed using TEM and Temperature programmed oxidation-mass spectroscopy (TPO-MS) following 200 h under an oxygen stream. The TEM and TPO-MS analysis results indicated a better anti-coking activity of the reduced catalyst along with a minimal concentration of platinum and palladium metals.

Silver-doped magnesia nanoparticles (Ag/MgO) were synthesized using the precipitation method and characterized by various techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), Brunner-Emmett-Teller (BET) surface area measurements, and dispersive X-ray spectroscopy (EDX). The morphology of Ag/MgO nanoparticles was determined by transmission and scanning electron microscopy, which revealed cuboidal shaped nanoparticles with sizes ranging from 31 to 68 nm and an average size of 43.5 ± 10.6 nm. The anticancer effects of Ag/MgO nanoparticles were evaluated on human colorectal (HT29) and lung adenocarcinoma (A549) cell lines, and their caspase-3, -8, and -9 activities, as well as Bcl-2, Bax, p53, cytochrome C protein expressions were estimated. Ag/MgO nanoparticles showed selective toxicity towards HT29 and A549 cells while remaining relatively innocuous towards the normal human colorectal, CCD-18Co, and lung, MRC-5 cells. The IC₅₀ values of Ag/MgO nanoparticles on the HT29 and A549 cells were found to be 90.2 ± 2.6 and 85.0 ± 3.5 μg/mL, respectively. The Ag/MgO nanoparticles upregulated caspase-3 and -9 activities, downregulated Bcl-2, upregulated Bax and p53 protein expressions in the cancer cells. The morphology of the Ag/MgO nanoparticle treated HT29 and A549 cells was typical of apoptosis, with cell detachment, shrinkage, and membrane blebbing. The results suggest that Ag/MgO nanoparticles induce apoptosis in cancer cells and exhibit potential as a promising anticancer agent.

Nickel, palladium, and platinum catalysts (1 wt.% each) supported on MgO and MgZrO to prepare Pt,Pd,Ni/Mg1-xZrxO catalysts (where x = 0, 0.03, 0.07, and 0.15), were synthesized by using co-precipitation method with K2CO3 as the precipitant. X-ray diffraction (XRD), X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM), H2-temperature programmed reduction (H2-TPR), and thermo gravimetric analysis (TGA) were employed to observe the characteristics of the prepared catalysts. The Pt,Pd,Ni/Mg0.85Zr0.15O showed the best activity in dry reforming of methane (DRM) with 99 % and 91 % for CO2 and CH4 conversions, respectively and 1.28 for H2/CO ratio at temperature 900 °C and 1:1 of CH4:CO2 ratio. The stability of Pt,Pd,Ni/Mg0.85Zr0.15O catalyst in the presence and absence of low stream 1.25 % oxygen was investigated. Carbon formation and amount in spent catalysts were examined by TEM and TGA in the presence of stream oxygen. The results showed that the amount of carbon was suppressed and negligible coke formation (less than 3 %) was observed. Several effects were observed with ZrO2 use as a promoter in the catalyst. Firstly, the magnesia cubic phase stabilized. Secondly, thermal stability and support for basicity increased. Thirdly, carbon deposition and the reducibility of Ni2+, Pd2+, and Pt2+ ions decreased.