Hydrogen evolution reaction (HER) on earth-abundant molybdenum disulfide (MoS 2) in acidic media is a robust process, but is kinetically retarded in alkaline media. Thus, improving the sluggish kinetics for HER in alkaline media is crucial for advancing the performance of water-alkali electrolyzers. Here, we demonstrate a dramatic enhancement of HER kinetics in base by judiciously hybridizing vertical MoS 2 sheets with another earth-abundant material, layered double hydroxide (LDH). The resultant MoS 2 /NiCo-LDH hybrid exhibits an extremely low HER overpotential of 78 mV at 10 mA/cm 2 and a low Tafel slope of 76.6 mV/dec in 1 M KOH solution. At the current density of 20 mA/cm 2 or even higher, the MoS 2 /NiCo-LDH composite can operate without degradation for 48 hr. This work not only brought forth a cost-effective and robust electrocatalyst, but more generally opened up new vistas for developing high-performance electrocatalysts in unfavorable media recalcitrant to conventional catalyst design.

Tough hydrogels, polymeric network structures with excellent mechanical properties (such as high stretchability and toughness), are emerging soft materials. Despite their remarkably mechanical features, tough hydrogels exhibit two flaws (freezing around the icing temperatures of water and drying under arid conditions). Inspired by cryoprotectants (CPAs) used in the inhibition of the icing of water in biological samples, a versatile and straightforward method is reported to fabricate extreme anti-freezing, non-drying CPA-based organohydrogels with long-term stability by partially displacing water molecules within the pre-fabricated hydrogels. CPA-based Ca-alginate/polyacrylamide (PAAm) tough hydrogels were successfully fabricated with glycerol, glycol, and sorbitol. The CPA-based organohydrogels remain unfrozen and mechanically flexible even up to -70 °C and are stable under ambient conditions or even vacuum.

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Significantly enhanced HER kinetics were achieved by controllably fabricating a stepped MoS2 surface structure which possesses more optimal free energy of H-adsorption.

Tough hydrogels, polymeric network structures with excellent mechanical properties (such as high stretchability and toughness), are emerging soft materials. Despite their remarkably mechanical features, tough hydrogels exhibit two flaws (freezing around the icing temperatures of water and drying under arid conditions). Inspired by cryoprotectants (CPAs) used in the inhibition of the icing of water in biological samples, a versatile and straightforward method is reported to fabricate extreme anti‐freezing, non‐drying CPA‐based organohydrogels with long‐term stability by partially displacing water molecules within the pre‐fabricated hydrogels. CPA‐based Ca‐alginate/polyacrylamide (PAAm) tough hydrogels were successfully fabricated with glycerol, glycol, and sorbitol. The CPA‐based organohydrogels remain unfrozen and mechanically flexible even up to −70 °C and are stable under ambient conditions or even vacuum.

Compared to the conventional perovskite solar cells (PSCs) containing hole-transport materials (HTM), carbon materials based HTM-free PSCs (C-PSCs) have often suffered from inferior power conversion efficiencies (PCEs) arising at least partially from the inefficient hole extraction at the perovskite-carbon interface. Here, we show that boron (B) doping of multiwalled carbon nanotubes (B-MWNTs) electrodes are superior in enabling enhanced hole extraction and transport by increasing work function, carrier concentration, and conductivity of MWNTs. The C-PSCs prepared using the B-MWNTs as the counter electrodes to extract and transport hole carriers have achieved remarkably higher performances than that with the undoped MWNTs, with the resulting PCE being considerably improved from 10.70% (average of 9.58%) to 14.60% (average of 13.70%). Significantly, these cells show negligible hysteretic behavior. Moreover, by coating a thin layer of insulating aluminum oxide (AlO) on the mesoporous TiO film as a physical barrier to substantially reduce the charge losses, the PCE has been further pushed to 15.23% (average 14.20%). Finally, the impressive durability and stability of the prepared C-PSCs were also testified under various conditions, including long-term air exposure, heat treatment, and high humidity.

Mechanism of metal catalysts controlling formation of single-wall carbon nanotubes AIP Conf.Carbon nanocapsules and singlelayered nanotubes produced with platinumgroup metals (Ru, Rh, Pd, Os, Ir, Pt) by arc discharge

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