We systematically investigate the doping of 24 homonuclear 3d transition metal configurations into the Ni2P(001). Our results reveal that the 1*Cr@Ni2P, 1*V@Ni2P, and 2*Ti@Ni2P are candidates for bifunctional hydrazine oxidation reaction (HzOR)/hydrogen evolution reaction (HER) electrocatalysis because they exhibit low formation energies and display more favorable Gibbs free energy barriers of the rate-determining steps (ΔGRDS) and optimal hydrogen adsorption Gibbs free energies (ΔGH*) compared to pure Ni2P(001). Our machine learning analyses indicate that the formation energy and the d-band center serve as key predictive descriptors for HzOR and HER activities, respectively. Moreover, constant-potential density functional theory calculations confirm that at pH = 7 and U = 0 V vs reversible hydrogen electrode, the 1*Cr@Ni2P, 1*V@Ni2P, and 2*Ti@Ni2P electrocatalysts exhibit excellent bifunctional activity, with ΔGRDS/ΔGH* values of 0.10/−0.37 eV, 0.22/−0.19 eV, and 0.20/−0.10 eV, respectively. Thus, this can significantly reduce practical implementation costs compared to harsh acidic or alkaline environments.
The flower-like hierarchical Ag/ZnTi-layered double hydroxide (ZnTi-LDH)/ZnIn2S4 S-scheme heterojunction was built by depositing plasmonic Ag nanoparticles and ZnTi-LDH nanosheets on ZnIn2S4 microspheres. The optimized catalyst under visible-light irradiation achieves a H2 evolution rate of 3462.41 μmol g−1 h−1, which is about six times greater than pure ZnIn2S4. Meanwhile, it had an excellent tetracycline degradation rate of 98.49% in 60 min. The formation of an internal electric field (IEF) and an S-scheme electron-transfer mechanism were confirmed by photoluminescence (PL) spectroscopy and in situ X-ray photoelectron spectroscopy (XPS). Moreover, density functional theory (DFT) simulations showed that interfacial electron transfer is spontaneous, which allows the effective spatial separation of photogenerated charge carriers. These results indicate that the integration of photothermal effects induced by plasmon with S-scheme heterojunctions is a promising approach to achieving the simultaneous enhancement of solar-driven hydrogen generation and environmental cleanup. This method has a lot of potential and should be explored due to its high photocatalytic efficiency.
A nickel-based ZSM-5 zeolite catalyst was synthesized via a one-pot approach for the hydrogen production via the water-gas shift reaction. Comprehensive characterization was performed using several complementary techniques. The presence of Ni species exhibiting different interactions with the support was evidenced by temperature-programmed reduction and near-ambient-pressure X-ray spectroscopy experiments.To compare performance, a catalyst with the same Ni loading was prepared via incipient wetness impregnation; both catalysts were active and selective for the water-gas shift reaction at 400 °C and 1 atm. Notably, the one-pot-synthesized catalyst, Ni2.4@ZSM-5, achieved higher CO conversion than the wet-impregnated catalyst, remained stable over 48 h of continuous operation (as shown by stability and on-off cycling tests), and exhibited high hydrogen selectivity. In situ DRIFT and NAP-XPS spectroscopy further revealed transient species, providing insights into the reaction mechanism.
Hydrogen has emerged as an alternative energy carrier used to decarbonize hard-to-electrify sectors and serve as a long-duration storage asset, but deployment pathways remain uncertain. Using a hydrogen-coupled capacity expansion model, we explore the policy, economic, and demand conditions necessary to support power-to-gas-to-power infrastructure in 2050. We find that steam methane reformation constitutes up to 78% of hydrogen production capacity even under optimistic cost and demand scenarios and that significant policy support is necessary for electrolyzer deployment. Fuel cell deployment is only viable under net-zero conditions and is limited by the need to meet end-use hydrogen demand, with only 33% of scenarios dispatching fuel cells for more than 24 h per year. Additionally, while storage from power-to-gas-to-power infrastructure can reduce power capacity requirements by up to 11%, projected large load growth could offset sector coupling benefits. Our results elucidate the conditions necessary for large-scale hydrogen deployment and its potential competitiveness.
The simultaneous photocatalytic hydrogen production and organic pollutant degradation offers an environmentally friendly and cost-effective strategy for energy generation and wastewater treatment. Herein, a Ti3C2 quantum dot-decorated ZnCo2O4/ZnIn2S4 (TC/ZCO/ZIS) composite was fabricated via condensation reflux and electrostatic self-assembly. The intimate ZCO/ZIS heterojunction and conductive Ti3C2 quantum dots promoted charge separation and electron transfer, achieving an H2 evolution rate of 27,221.4 μmol h−1 g−1 with triethanolamine. Using 2-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol as electron donors, degradation efficiencies reached 92.0%, 84.0%, and 81.3% after 4 h, accompanied by H2 evolution rates of 468.4, 407.3, and 319.5 μmol h−1 g−1, respectively. Characterization and mechanism studies confirmed that the synergistic heterojunction and Ti3C2 quantum dots accelerated charge separation, providing an efficient dual-functional photocatalyst for wastewater remediation and sustainable hydrogen production.
