Generating highly active oxide-phosphide heterostructure through interfacial engineering to break the energy scaling relation toward urea-assisted natural seawater electrolysis

Urea-assisted natural seawater electrolysis is an emerging technology that is effective for grid-scale carbon-neutral hydrogen mass production yet challenging.Circumventing scaling relations is an effective strategy to break through the bottleneck of natural seawater splitting.Herein,by DFT calculation,we demonstrated that the interface boundaries between Ni_(2)P and MoO_(2) play an essential role in the selfrelaxation of the Ni-O interfacial bond,effectively modulating a coordination number of intermediates to control independently their adsorption-free energy,thus circumventing the adsorption-energy scaling relation.Following this conceptual model,a well-defined 3D F-doped Ni_(2)P-MoO_(2) heterostructure microrod array was rationally designed via an interfacial engineering strategy toward urea-assisted natural seawater electrolysis.As a result,the F-Ni_(2)P-MoO_(2) exhibits eminently active and durable bifunctional catalysts for both HER and OER in acid,alkaline,and alkaline sea water-based electrolytes.By in-situ analysis,we found that a thin amorphous layer of NiOOH,which is evolved from the Ni_(2)P during anodic reaction,is real catalytic active sites for the OER and UOR processes.Remarkable,such electrode-assembled urea-assisted natural seawater electrolyzer requires low voltages of 1.29 and 1.75 V to drive 10 and600 mA cm^(-2)and demonstrates superior durability by operating continuously for 100 h at 100 mA cm^(-2),beyond commercial Pt/C||RuO_(2) and most previous reports.

Exploring catalytic behaviors of CoS_(2)-ReS_(2) heterojunction by interfacial engineering

Herein, a stable and efficient CoS_(2)-ReS_(2) electrocatalyst is successfully constructed by using the different molar ratios of CoS_(2) on ReS_(2). The size and morphology of the catalysts are significantly changed after the CoS_(2) is grown on ReS_(2), providing regulation of the catalytic activity of ReS_(2). Particularly, the optimized CoS_(2)-ReS_(2) shows superior electrocatalytic properties with a low voltage of 1.48 V at 20 mA cm^(-2) for overall water splitting in 1.0 M KOH, which is smaller than the noble metal-based catalysts(1.77 V at 20 mA cm^(-2)). The XPS, XAS, and theoretical data confirm that the interfacial regulation of ReS_(2) by CoS_(2) can provide rich edge catalytic sites, which greatly optimizes the catalytic kinetics and drop the energy barrier for oxygen/hydrogen evolution reactions. Our results demonstrated that interfacial engineering is an efficient route for fabricating high-performance water splitting electrocatalysts.