Hu Yi,Xu Jingsong,Zhang Tianzhu,Zhong Hang,Chen Jun,Liu Xinai,Pan Qifa,Liu Ruidong,Jiang Chunli,Chen Jun
Electrocatalytic water splitting to produce hydrogen is a promising route to provide green hydrogen on a large scale. To explore non-noble metal electrocatalysts with high performance is still a challenge. Herein, a one-step electrodeposition way is developed to construct the heterostructural (NiO-La 2 O 3 )/(Ni-La)/NiO/Ni electrocatalysts on Ni foam. The dark Ni-La coating was prepared by co-electrodeposition from an aqueous solution containing LaCl 3 and NiCl 2 with a molar concentration ratio of 1:5. Among these heterostructural Ni-based electrocatalysts, an excellent HER activity is achieved: an overpotential of 22 mV at the current density of 10 mA cm −2 in 1 M KOH solution. It is demonstrated that the introduction of La significantly reduces the overpotential for HER. The higher the La content in the Ni-La coating of these electrocatalysts, the better the electrocatalytic HER performance was exhibited. This work provides a facile and inexpensive route to prepare Ni-La coating on electrodes in an aqueous solution.
Nickel electrodes under continuous potential cycling were applied for the electrooxidation of benzyl alcohol and glycine in KOH solutions, and their activities were measured and compared by cyclic voltammetry. It is shown that intrinsic activities of both reactions decrease with the increasing catalyst loadings, and a more significant decreasing trend was observed in glycine electrooxidation when compared to benzyl alcohol electrooxidation. These phenomena may be explained by an increasing of mass loading induced a decrease of the catalyst surface conductivity, structure changes of Ni(OH)2from α-phase to β-phase, and the intercalation of glycine molecules into nickel hydroxide interlayers.
Designing a Z-scheme heterojunction is of great significance to achieve high separation of photogenerated carriers and strong photo-redox properties of two semiconductor materials . In photosynthesis, the effects of photocatalytic electrolytes (adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH)) on chemical energy has attracted numerous interests. In this case, developing photocatalytic electrolytes with more active site and efficient charge extraction and separation would be beneficial for superior photocatalytic activity in Z-scheme system. Herein, we synthesized a Black/Red (BP/RP) phosphorus Z-scheme hybrid via a feasible two-steps sonochemical method, and the adding photocatalytic electrolytes ATP and NADPH in KOH solution endow the system with new vitality in photocatalysis . Consequently, photoelectrochemical (PEC) tests demonstrated the as-prepared BP/RP Z-scheme hybrid exhibits enhanced photocurrent of 9 μA/cm 2 at 0.5 V compared to the sole RP, while adding NADPH and ATP, the photocurrent of BP/RP Z-scheme hybrid shows dramatic increment of 30 μA cm −2 at a bias potential of 0.6 V. The improved photocatalytic activity is ascribed to the abundant active sites, higher carrier mobility of the BP/RP Z-scheme system, as well as the efficient photogenerated carrier separation and the prolonged lifetime of photocatalytic electrolytes. This work demonstrated the photocatalytic electrolytes can meet the unity of coordination and efficiency of achieving efficient PEC catalytic in the Z-Scheme system, and provides positive ideas for the possibility and superiority for other 2D materials in the field of ultrafast Photonics , photodetectors , etc.