A Ta-TaS2 monolith catalyst with robust and metallic interface for superior hydrogen evolution

Abstract

The use of highly-active and robust catalysts is crucial for producing green hydrogen by water electrolysis as we strive to achieve global carbon neutrality. Noble metals like platinum are currently used catalysts in industry for the hydrogen evolution, but suffer from scarcity, high price and unsatisfied performance and stability at large current density, restrict their large-scale implementations. Here we report the synthesis of a type of monolith catalyst consisting of a metal disulfide (e.g., tantalum sulfides) vertically bonded to a conductive substrate of the same metal tantalum by strong covalent bonds. These features give the monolith catalyst a mechanically-robust and electrically near-zero-resistance interface, leading to an excellent hydrogen evolution performance including rapid charge transfer and excellent durability, together with a low overpotential of 398 mV to achieve a current density of 2,000 mA cm−2 as required by industry. The monolith catalyst has a negligible performance decay after 200 h operation at large current densities. In light of its robust and metallic interface and the various choices of metals giving the same structure, such monolith materials would have broad uses besides catalysis.

Recent Advances in Design of Electrocatalysts for High‐Current‐Density Water Splitting

“…Batch-type cell, 1 m KOH, on Ni foam, electrode area: ≈1 cm 2 [40] MoC 2 /MoS 2 220 mV @ 1000 mA cm -2 Batch-type cell, 1 m KOH, on Ti foil, electrode area: ≈1 cm 2 [24] h-NiMoFe 97 mV @ 1000 mA cm -2 Batch-type cell, 1 m KOH, on Ni foam, electrode area: 1 cm 2 [41] GDY/MoO 3 1850 mV @ 1200 mA cm -2 Batch-type cell, 0.1 m KOH, on Cu foam, electrode area: 1 cm 2 [26] CoP HNS/CF 180 mV @ 500 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4 , on carbon foam, electrode area: ≈1 cm 2 [42] 2H-Nb 1.35 S 2 420 mV @ 5000 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4 , on glassy carbon, electrode area: not referred to [25] Ta-TaS 2 398 mV @ 2000 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4 , material itself as both electrodes and catalyst, electrode area: ≈1 cm 2 [43] MoC 2 /MoS 2 227 mV @ 1000 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4 , on Ti foil, electrode area: ≈1 cm 2 [24] α-MoB 2 334 mV @ 1000 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4 , on Cu foil, electrode area: ≈1 cm 2 [44] PtGa 113 mV @ 600 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4, material itself acts as both electrode and catalyst, electrode area: not referred to [21] HC-MoS 2 /Mo 2 C 414 mV @1000 mA cm -2 Batch-type cell, 0.5 m H 2 SO 4 , on Cu foam, electrode area: ≈1 cm 2 [45] Ta-TaS 2 (HER) || IrO 2 1.98 V @ 1000 mA cm -2 PEM electrolyzer, ambient condition, electrode area: 1 cm 2 [43] CoP (HER) || IrO x 2.02 V @ 1860 mA cm -2 PEM electrolyzer, at 55 °C, 400 psi, electrode area: 86 cm 2 [22] Pd/PG (HER) || RuO 2 2.32 V @ 2000 mA cm -2 PEM electrolyzer, at 80 °C, catalyst on PEM, electrode area: 25 cm 2 [46] Mo 3 S 13 -NCNT (HER) || IrO 2 2.36 V @ 4000 mA cm -2 PEM electrolyzer, at 80 °C, on carbon cloth, electrode area: 5 cm 2 [47] MoP|S-CB (HER) || Ir/C 1.81 V @ 500 mA cm -2 PEM electrolyzer, at 80 °C, on carbon paper, electrode area: 5 cm 2 [23] NiCu mixed metal oxide (HER) || Ir/C 2.0 V @ 1850 mA -2 AEM electrolyzer, at 50 °C, on carbon paper, electrode area: 25 cm 2 [48] OER Co-doped FeNi carbonate hydroxide 254 mV @ 500 mA cm -2 Batch-type cell,1 m KOH, on Ni foam, electrode area: ≈1 cm 2 [29] Nanostructured NiFe (oxy)hydroxide 261 mV @ 500 mA cm -2 Batch-type cell, 1 m KOH, on Ni foam. electrode area: ≈1 cm 2 [30] Ni-Fe oxyhydroxide @ NiFe alloy 248 mV @ 500 mA cm -2 258 mV @ 1000 mA cm -2 Batch-type cell, 1 m KOH, on Ni foam.…”

Synthesis of Nickel Nitride‐Based 1D/0D Heterostructure via a Morphology‐Inherited Nitridation Strategy for Efficient Electrocatalytic Hydrogen Evolution

“…Moreover, the corresponding elemental mapping images (Figure 2g) also exhibit shortage of Mo element around the nanoparticles, demonstrating the nanoparticles exist as Ni 3 N instead of Ni 0.2 Mo 0.8 N. It should be pointed out that the interface of the as‐obtained 1D Ni 0.2 Mo 0.8 N/0D Ni 3 N heterostructure is intimate in view of them deriving from the same oxide precursor, as should favor the interface electron transfer. [ 32 ] The above results integrally reveal that the nitrided sample exists as the intimate heterostructure composed of 1D Ni 0.2 Mo 0.8 N and 0D Ni 3 N.…”

Recent progress on the long‐term stability of hydrogen evolution reaction electrocatalysts

“…Ta-TaS 2 MC 0.5 M H 2 SO 4 2000@398 -@200@--20 000@- [44] N-WC nanoarray 0.5 M H 2 SO 4 193 144@10@97.1% + 156@10@98.1% --…”