Mesoporous LDH Metastructure from Multiscale Assembly of Defective Nanodomains by Laser Shock for Oxygen Evolution Reaction

Abstract

Laser is a powerful tool for the synthesis of nanomaterials. The intensive laser pulses delivered to materials within nanoseconds allow the formation of novel structures that are inaccessible for conventional methods. Layered double hydroxide (LDH) nanostructures with high porosity, suitable dopants, and rich defects are desirable for catalysts, however, tremendously difficult in a one‐pot synthesis. Here it is found that confined laser shock in solvent leads to the formation of nanoreactors which guide the assembly of multiscale LDH building units, larger nanosheets as frame and smaller nanodomains as building blocks. These nanodomains have rich vacancy defects and are interlocked in a high packed density of 1013 cm−2, leaving rich mesopores across the nanosheets and coral‐like morphology. Like the natural coral reef that has multiscale structure to accommodate different marine organisms, the coral‐like LDH metastructure provides large surface area and rich active sites for the interaction with guest molecules. Benefiting from the multiscale porous structure and rational dopant, this LDH catalyst exhibits a low overpotential of 220 mV at 10 mA cm−2 for oxygen evolution reaction (OER), standing as one of the best LDH catalysts to date.

Recent Advances on Transition‐Metal‐Based Layered Double Hydroxides Nanosheets for Electrocatalytic Energy Conversion

“…CoV-LDHs 1 m KOH 250 @ 10 44 [58] NiFe-LDHs 1 m KOH 270 @ 10 48.6 [59] NiFe-LDHs-MPs 1 m KOH 250 @ 100 34.5 [51] NiFe-LDHs 1 m KOH 324 @ 10 57.4 [60] CoNi-LDHs-E 1 m KOH 280 @ 10 81 [61] Ta-NiFe LDHs 1 m KOH 260 @ 50 58.95 [62] D-NiFe LDHs 1 m KOH 199 @ 10 26.9 [52] NiFe LDHs/Co 1−x S 1 m KOH 251 @ 10 41.67 [63] NiFeV-LDHs 1 m KOH 195 @ 20 42 [64] NiFe III (1:1)-LDHs 1 m KOH 183 @ 10 31.1 [65] NiCo 1 Fe 1 -LDHs 1 m KOH 231 @ 10 59 [66] CoVRu-LDHs 1 m KOH 263 @ 25 74.5 [53] Fe-NiV-LDHs 1 m KOH 255 @ 10 56 [67] NiFeV-LDHs 1 m KOH 224 @ 10 32.7 [68] NiFeNb-0.25-LDHs 1 m KOH 277 @ 100 50.6 [69] NiFeCo-LDHs 1 m KOH 249 @ 10 42 [70] v-NiFe-LDHs 1 m KOH 195 @ 10 47.9 [71] EE-NiFe-LDHs 1 m KOH 205 @ 10 41.8 [72] NiCoFe-LDHs 1 m KOH 174 @ 10 50 [73] NiFe-LDHs-V Ni 1 M KOH 229 @ 10 62.9 [74] v-NiFe-LDHs 1 m KOH 150 @ 10 37.1 [75] D-NiFeZn-LDHs 0.1 m KOH 200 @ 20 34.9 [54] NiFe-LDHS-V O 1 m KOH 230 @ 10 39.6 [76] D-CoFe-LDHs 1 m KOH 283 @ 10 39 [77] MnNiFe-LDHs-laser 1 m KOH 220 @ 10 37 [78] M-NiFe-LDHs 1 m KOH 217 @ 10 45.1 [79] AGC/MnCo-LDHs 1 m KOH 370 @ 10 127.5 [80] Co-C@NiFe-LDHs 1 m KOH 249 @ 10 57.9 [56] FeNi-LDHs/CoP 1 m KOH 231@ 20 33.5 [81] FeCoNi-LDHs/CuO/Cu 1 m KOH 243.1 @ 50 63.8 [57] FeNi 2 Se 4 -FeNi-LDHs 1 m KOH 205 @ 10 30.14 [55] MIM-CoFe-LDHs 1 m KOH 216.8@10 39.3 [82] CoNi-LDHs/Ti 3 C 2 T x 1 m KOH 200 @ 50 68 [83] CoNi-LDHs@PCPs 1 m KOH 350 @ 10 58 [84] Ni 3 S 2 /Cu-NiCo-LDHs 1 m KOH 119 @ 10 70 [85] NiCo-LDHs/NiCoS 1 m KOH 308@ 100 48 …”

Co‐Adjusting d‐Band Center of Fe to Accelerate Proton Coupling for Efficient Oxygen Electrocatalysis

“…The pyrolysis and phosphating process break the continuous crystal structure of CoFe-LDH nanosheets, resulting in the formation of plentiful mesopores. [39,40] The mesopores facilitate the formation of a rich three-phase interface for the oxygen electrocatalytic reaction. [41] The analysis of XRD, BET, SEM, and TEM confirmed the successful preparation of CoFeP@NBC catalysts with morphology and crystal structure.…”

Tungstate Intercalated NiFe Layered Double Hydroxide Enables Long‐Term Alkaline Seawater Oxidation

“…[26][27][28][29] In particular, the layered double hydroxides (LDHs) with a 2D sheet structure, provide a larger surface area and expose more active sites for the reaction. [30][31][32] Transition metal layered materials, such as NiFe LDH are widely used in OER process. [33] Generally, the outstanding water oxidation activity of NiFe LDH under alkaline electrolyte arises in that surface metal sites are prone to form species at higher valence states (e.g., 𝛾-NiOOH), which are real active sites for electrocatalysis reaction.…”