Construction of hierarchical nickel cobalt selenide complex hollow spheres for pseudocapacitors with enhanced performance

Conversion Reaction Mechanism of Ultrafine Bimetallic Co‐Fe Selenides Embedded in Hollow Mesoporous Carbon Nanospheres and Their Excellent K‐Ion Storage Performance

“…The XRD patterns of all composites composed of bimetallic selenides are slightly shifted in comparison with those of the mono-metal selenides, owing to the formation of a solid-solution. [25,26] The crystal structures of CFSe/C-250, -300, and -500 composites are well matched with those of hexagonal (Co 0.5 Fe 0.5 ) 0.85 Se, orthorhombic (Co 0.5 Fe 0.5 )Se 2 , and monoclinic (Co 0.5 Fe 0.5 ) 3 Se 4 , respectively. For each reaction temperature, the bimetallic selenides have the most stable crystal phase at that temperature; additionally, their crystalline sizes increase with temperature.…”

Expanding Multinary Selenide Based High-Efficiency Oxygen Evolution Electrocatalysts through Combinatorial Electrodeposition: Case Study with Fe–Cu–Co Selenides

“…The spectrum of Fe 2p in Figure c showed peaks at 708.45 and 722.27 eV corresponding to Fe 2+ , while peaks at 710.26 and 724.75 eV were assigned to Fe 3+ with satellite peaks at 716.08 and 730.57 eV. − In the Cu 2p spectrum as shown in Figure d, peaks at 930.32 and 950.12 eV were attributed to Cu + , and those at 932.16 and 952.23 eV corresponded to Cu 2+ respectively. Peaks at 939.75 and 960.15 eV were assigned to the satellite peaks. , In the Co 2p spectrum shown in Figure e, peaks at 779.14 and 794.48 eV referred to Co 2+ , and those at 783.80 and 800.61 eV corresponded to its satellite peaks, respectively. , In the Se 3d spectrum shown in Figure f, peaks at 55.24 and 56.22 eV were assigned to Se 3d 5/2 and Se 3d 3/2 respectively, while the big sharp peak around 59.0 eV was attributed to SeO x which might be a result of the surface oxidation of selenide. , The deconvoluted spectra revealed that both Fe 2p and Cu 2p were mixed valence metal cations, while Co 2p was present as only divalent ions. The XPS spectra also confirmed that the film composition was exclusively selenide with no indication of presence of other metal oxide/oxyhydroxide impurity.…”

“…79,80 In the Se 3d spectrum shown in Figure 5f, peaks at 55.24 and 56.22 eV were assigned to Se 3d 5/2 and Se 3d 3/2 respectively, while the big sharp peak around 59.0 eV was attributed to SeO x which might be a result of the surface oxidation of selenide. 81,82 The deconvoluted spectra revealed that both Fe 2p and Cu 2p were mixed valence metal cations, while Co 2p was present as only divalent ions. The XPS spectra also confirmed that the film composition was exclusively selenide with no indication of presence of other metal oxide/ oxyhydroxide impurity.…”

Regulation of the morphology and electrochemical properties of Ni0.85Se via Fe doping for overall water splitting and supercapacitors

“…In the HRTEM image (Fig. 3f), there are two well-resolved lattice fringes with interplanar distances of 0.27 nm and 0.29 nm, which can be indexed to the spacings of the (101) and (300) crystal planes of Ni 0.85 S and NiSe, 49,50 respectively.…”