In this work, a highly active H2 evolution NiS x catalyst decorated on graphene (NiS x /G) nanohybrid was prepared by an in situ chemical deposition method, in which nickel ion was first adsorbed onto graphene and subsequently reacted with sulfide ion to yield the NiS x /G nanohybrid. The NiS x /G catalyst exhibited activity for hydrogen generation 2-fold higher than that of pristine NiS x under visible light irradiation. The highest quantum efficiency of 32.5% was reached at 430 nm when Eosin Y was used as a photosensitizer. In this system, graphene not only provided a large area and two-dimensional substrate for the confined growth of NiS x but also greatly enhanced the transfer of photoelectrons from excited Eosin Y to the NiS x cocatalyst because of its promotion of charge separation, leading to the great enhancement of photocatalytic hydrogen evolution.

Water splitting via two two-electron processes (the H 2 O first photocatalytically converted to H 2 and H 2 O 2 under visible light irradiation and then the H 2 O 2 disproportionation to H 2 O and O 2 by a thermal catalytic process) has attracted extensive attention recently. 1,2 Contrary to these reports, we found that not only the photocatalytic H 2 generation could be driven by visible light but also the two-electron H 2 O 2 disproportionation to form H 2 O and O 2 could also be photocatalyzed by visible light over g-C 3 N 4 catalysts. Photocatalytic H 2 , O 2 generation, and simultaneous H 2 O 2 formation in Cu/C 3 N 4 and Fe/C 3 N 4 dispersions were confirmed, about 2.1 and 1.4 μmol of H 2 and 0.8 and 0.5 μmol of O 2 evolved over Cu/C 3 N 4 and Fe/C 3 N 4 in 12 h, respectively. To prove the photocatalytic process of H 2 O 2 disproportionation, the H 2 O 2 was added as a reagent in g-C 3 N 4 , Cu/C 3 N 4 , and Fe/C 3 N 4 dispersions. The results showed that the activity of H 2 evolution decreased with the increase of H 2 O 2 concentration; the corresponding AQEs of oxygen formation were 16.1%, 42.6%, and 78.5% at 400 nm, respectively. The remarkable increase of anodic photocurrents over Fe/ C 3 N 4 /ITO and Cu/C 3 N 4 /ITO electrodes indicated that the two-electron H 2 O 2 disproportionation was catalyzed via surface photocatalytic mechanism. The ESR results implied reaction occurred by O 2 − • radical path over g-C 3 N 4 under irradiation.

Survival of KRAS mutant pancreatic cancer is critically dependent on reprogrammed metabolism including elevated macropinocytosis, autophagy, and lysosomal degradation of proteins. Lysosomal acidification is indispensable to protein catabolism, which makes it an exploitable metabolic target for KRAS mutant pancreatic cancer. Herein we investigated ultra-pH-sensitive micelles (UPSM) with pH-specific buffering of organelle pH and rapid drug release as a promising therapy against pancreatic cancer. UPSM undergo micelle–unimer phase transition at their apparent pK a, with dramatically increased buffer capacity in a narrow pH range (<0.3 pH). Cell studies including amino acid profiling showed that UPSM inhibited lysosomal catabolism more efficiently than conventional lysosomotropic agents (e.g., chloroquine) and induced cell apoptosis under starved condition. Moreover, pH-triggered rapid drug release from triptolide prodrug-loaded UPSM (T-UPSM) significantly enhanced cytotoxicity over non-pH-sensitive micelles (T-NPSM). Importantly, T-UPSM demonstrated superior safety and antitumor efficacy over triptolide and T-NPSM in KRAS mutant pancreatic cancer mouse models. Our findings suggest that the ultra-pH-sensitive nanoparticles are a promising therapeutic platform to treat KRAS mutant pancreatic cancer through simultaneous lysosomal pH buffering and rapid drug release.

Thiomolybdate [MoS] nanoclusters, as a molecular mimic of MoS edge sites, showed high efficiency in catalyzing photochemical H evolution from a molecular system of Ru(bpy)Cl-ascorbic acid (HA) under visible light irradiation (≥420 nm), providing a turnover number of 1570 and an initial turnover frequency of 335 h for H evolution based on the [MoS] catalyst.