Ionothermal synthesis of three-dimensional hierarchical Ni₃Se₂mesoporous nanosheet networks with enhanced performance for asymmetric supercapacitors

Abstract

Ni3Se2 3D hierarchical mesoporous architectures comprising 2D nanosheets are synthesized through an ionothermal process, delivering exceptional electrochemical performance in supercapacitors.

Synthesis of bimetallic nickel cobalt selenide particles for high-performance hybrid supercapacitors

“…The corresponding devices are NiSe–Se@NF//AC@Ni (29.9 W h kg −1 at 594.46 W kg −1 ), 41 NCS/NGF//AC (36.8 W h kg −1 at 375 W kg −1 ), 42 NiSe@MoSe 2 //N-PMCN (32.6 W h kg −1 at 415 W kg −1 ), 43 Ni 0.85 Se@MoSe 2 //GNS (25.5 W h kg −1 at 420 W kg −1 ), 44 Ni 3 Se 2 -24//AC (22.3 W h Kg −1 at 160.4 W kg −1 ), 32 NiSe 2 @CNT//AC (25.61 W h kg −1 at 810 W kg −1 ), 45 NiCo 2 O 4 @Ni 0.85 Se//AC (29.3 W h kg −1 at 799 W kg −1 ), 46 Ni 3 Se 2 3D HMNN//AC (38.4 W h kg −1 at 794.5 W kg −1 ). 37 These above results suggest that the Ni 0.95 Co 2.05 Se 4 //C device possesses remarkable energy storage capability and cycling stability, which demonstrate greatly practical applications in energy storage devices.…”

“…3d), there is a pair of metal-selenium bonds, which indicates the presence selenium ions in Ni 0.95 Co 2.05 Se 4 nanoparticles. The broad peak situated at 57.24 eV reects surface Se species with a high oxidation state (SeO x ), 36,37 which is attributed to a small amount of oxidation on the surface.…”

Maximizing Redox Charge Storage via Cation (V)–Anion (S) Dual Doping on Nickel Diselenide Nanodiscs for Hybrid Supercapacitors

“…Figure c displays CV curves of V, S-NiSe 2 in the scan rate range of 2–75 mV s –1 and potential regime of 0–0.5 V. A pair of redox peaks is distinctly observed with increasing scan rates, indicating good electronic conduction of V, S-NiSe 2 . Although, oxidation and reduction peaks shift slightly owing to polarization and internal resistance, , the shape of the CV curves remained mostly unchanged at lower scan rates, indicating complete OH – ion insertion at lower scan rates Figure d illustrates the GCD curves of V, S-NiSe 2 in the potential range of 0–0.45 V (vs SCE) with C sp values of 1464 (1 A g –1 ), 1354 (2 A g –1 ), 1285 (3 A g –1 ), 1147 (4 A g –1 ), 1132 (8 A g –1 ), and 1064 F g –1 (9 A g –1 ).…”

“…Although, oxidation and reduction peaks shift slightly owing to polarization and internal resistance, 49,50 the shape of the CV curves remained mostly unchanged at lower scan rates, indicating complete OH − ion insertion at lower scan rates. 51 Figure 4d illustrates the GCD curves of V, S-NiSe 2 in the potential range of 0−0.45 V (vs SCE) with C sp values of 1464 (1 A g −1 ), 1354 (2 A g −1 ), 1285 (3 A g −1 ), 1147 (4 A g −1 ), 1132 (8 A g −1 ), and 1064 F g −1 (9 A g −1 ). Additionally, voltage plateaus at approximately 0.25 V confirmed the redox behavior of V, S-NiSe 2 , as suggested previously from CV results.…”

Three‐In‐One Alkylamine‐Tuned MoOx for Lab‐Scale to Real‐Life Aqueous Supercapacitors

“…Figure 7e shows the Ragone plot of the assembled MoO x -HDA-3//MnO 2 device compared with other recently reported representative devices. It is noteworthy that the MoO x -HDA-3//MnO 2 device presents an ultrahigh energy density of 78.2 Wh kg −1 at 300 W kg −1 and 30.4 Wh kg −1 at 3172 W kg −1 , which is better than most of the recently reported devices, for example, RuO 2 @COF (23.3 Wh kg −1 , 261 W kg −1 ), [46] Bi 2 Se 3 @Co 0.85 Se (30.9 Wh kg −1 , 559 W kg −1 ), [47] NiCoP@GO (32.9 Wh kg −1 , 1301 W kg −1 ), [48] C-GMOF@AC (30.3 Wh kg −1 , 137 W kg −1 ), [49] LDH-NF@ VG (56.8 Wh kg −1 , 260 W kg −1 ), [50] Ni 3 Se 2 @AC (38.4 Wh kg −1 , 794.5 W kg −1 ), [51] CoP@FeP 4 (46.3 Wh kg −1 , 695 W kg −1 ), [52] MXene@CNT-HQ (62 Wh kg −1 , 281 W kg −1 ), [53] MnO 2 -GO@CGO (31.8 Wh kg −1 , 453 W kg −1 ), [54] Li 4 Ti 5 O 12 @NGO (26.2 Wh kg −1 , 799 W kg −1 ), [55] NCNs-0.1@AC (43.02 Wh kg −1 , 840.3 W kg −1 ), [56] rP-rGO@Ni 2 P (41.66 Wh kg −1 , 1200 W kg −1 ), [57] and RGO@ Mn 3 O 4 (23.5 Wh kg −1 , 990 W kg −1 ). [58] More importantly, at 100 mV s −1 , 97% specific capacitance of the assembled MoO x -HDA-3//MnO 2 device is retained after 30 000 cycles, which indicates a practical long-cycle stability.…”