Time series-based prediction of antibiotic degradation via photocatalysis using ensemble gradient boosting

This study aims to evaluate the effectiveness of the laboratory-made catalyst Ni2P-ZrO2 (NPZ) in the degradation of an antibiotic in an aqueous suspension when exposed to ultraviolet (UV) light. The degradation of amoxicillin (AMX) was predicted using time series forecasting through the ensemble gradient boosting model. The degradation experiments were conducted utilizing two distinct photocatalyst compositions of Nickel phosphide-zirconium dioxide (NPZ) in the proportions of 1:9 and 2:8. The most effective experimental results were obtained using a natural pH, a catalyst concentration of 0.20 g/L and reaction duration of 0.5 h after testing the different catalysts. Experimental data were used for training, validating and confirming time series predictions. The use of ensemble technique highly affected the experimental findings. The model's performance was quite satisfactory in terms of correlation coefficient (94.00%), normalized mean square error (0.01) and mean square root error (0.0911) which significantly contributed to the model's accuracy. All input variables, such as pH, catalyst dose and irradiation time, had a significant impact on the degrading efficacy. The study has demonstrated that time series forecasting can be used for predicting the degradation process precisely.

Interfacial nanoarchitectonics of nickel phosphide supported on activated carbon for transfer hydrogenation of nitroarenes under mild conditions

Metal phosphides are promising catalysts for hydrogenation reactions due to their unique ability to generate active hydrogen species which are essential for desired reactions. In this work, the hydrogenation potential of nickel phosphide (Ni2P) is explored for the transfer hydrogenation of aromatic nitro compounds using hydrazine hydrate as hydrogen source. The Ni2P was supported on activated carbon (AC) to facilitate highly exposed active reaction sites. The as-synthesized Ni2P-AC catalyst showed excellent catalytic potential for the hydrogenation of nitro compounds to corresponding amines with 100% conversion efficiency and resulted in excellent yields. The reaction conditions were optimized by varying different reaction parameters, such as time, temperature, solvents, catalyst amount and hydrogen sources. The developed reaction protocol is highly selective for nitro compounds having reduction susceptible functional groups like -Cl, -Br, -CHO, etc. The structure-activity relationship of the Ni2P-AC was also examined which suggested that both acidic and basic sites present in Ni2P-AC catalyst plays crucial role in hydrogenation reaction. Besides, an in-depth insight into the reaction mechanism illustrates that the reaction proceeds via N-phenyl hydroxylamine as the reaction intermediate. In addition, decent recyclability and stability of Ni2P-AC catalyst demonstrates its highly versatile nature for potential large-scale applications. The use of highly efficient Ni2P-AC catalyst for hydrogenation reactions can lead the way towards sustainable and effective industrial organic catalysis.

NiCoP modified lead-free double perovskite Cs2AgBiBr6 for efficient photocatalytic hydrogen generation

A NiCoP/Cs2AgBiBr6 composite was successfully synthesised via electrostatic coupling to achieve a hydrogen generation rate of 12.5%, which was ∼88 times higher than that of pure Cs2AgBiBr6.

Triphenylphosphine-Assisted Transformation of NiS to Ni2P through a Solvent-Less Pyrolysis Route: Synthesis and Electrocatalytic Performance

Straightforward synthetic routes to the preparation of transition metal phosphides or their chalcogenide analogues are highly desired due to their widespread applications, including catalysis. We report a facile and simple route for the preparation of a pure phase nickel phosphide (Ni₂P) and phase transformations in the nickel sulfide (NiS) system through a solvent-less synthetic protocol. Decomposition of different sulfur-based complexes (dithiocarbamate, xanthate, and dithiophosphonate) of nickel(II) was investigated in the presence and absence of triphenylphosphine (TPP). The optimization of reaction parameters (nature of precursor, ratio of TPP, temperature, and time) indicated that phosphorus- and sulfur-containing inorganic dithiophosphonate complexes and TPP (1:1 mole ratio) produced pure nickel phosphide, whereas different phases of nickel sulfide were obtained from dithiocarbamate and xanthate precursors in the presence or absence of TPP. A plausible explanation of the sulfide or phosphide phase formation is suggested, and the performance of Ni₂P was investigated as an electrocatalyst for supercapacitance and overall water-splitting reactions. The performance of Ni₂P with the surface free of any capping agents is not well explored, as common synthetic methods are solution-based routes; therefore, the electrocatalytic performance was also compared with metal phosphides, prepared by other routes. The highest specific capacitance of 367 F/g was observed at 1 A/g, and the maximum energy and power density of Ni₂P were calculated to be 17.9 Wh/kg and 6951 W/kg, respectively. The prepared nickel phosphide required overpotentials of 174 and 316 mV along with Tafel slopes of 115 and 95 mV/dec to achieve a current density of 10 mA/cm² for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively.

Comparison of four different synthetic routes of Ni2P/TiO2–Al2O3 catalysts for hydrodesulfurization of dibenzothiophene

A highly active Ni₂P/TiO₂–Al₂O₃ catalyst was simply synthesized at a much lower temperature (573 K) than previously reported methods (973 K).