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Exploring high-efficiency, low-cost, and stable photocatalysts that enable full solar spectrum including UV, visible, and near-infrared (NIR) light utilization for photocatalytic hydrogen generation still faces huge challenge. Herein, a Co2P/CdS Z-scheme photocatalyst without a noble metal is rationally fabricated to achieve ultrabroad UV–vis–NIR harvesting. Compared to Pt/CdS, CdS, and Co2P, the optimized Co2P/CdS exhibits much more outstanding performance with the H2generation rates of 262.16, 66.98, and 3.93 mmol/g/h under solar, visible (780 nm > λ > 420 nm), and NIR (λ > 780 nm) light, respectively. Particularly, 10% Co2P/CdS displays a prominent apparent quantum efficiency value of 2.26% at 700 nm. The Z-scheme transform route can effectively enhance the separation of charge carriers in Co2P/CdS for UV–vis-driven HER, as confirmed by photoluminescence and photoelectrochemical measurements. More importantly, the Co–S bonds at the interface demonstrated by Fourier transform infrared, Raman (mapping), and X-ray photoelectron spectroscopy and density functional theory calculations can act as a “bridge” for charge transfer, thereby enhancing the full spectrum-driven H2evolution. To the best of our knowledge, this is a rare research on full spectrum-driven photocatalytic HER without a noble metal.

Ceramic Li1.3Al0.3Ti1.7(PO4)3(LATP) with high ionic conductivity and stability in ambient atmosphere is considered to be potent as a solid-state electrolyte of solid-state lithium metal batteries (SSLMBs), but its huge interfacial impedance with electrodes and the unwanted Ti4+-mediated reduction reaction caused by the lithium (Li) metal anode greatly limit its application in LMBs. Herein, a composite polymer electrolyte (CPET) was integrated by in situ gelation of dual-permeable 1, 3-dioxolane (DOL) in the tandem framework composed of the commercial cellulose membrane TF4030 and a porous three-dimensional (3D) skeleton-structured LATP. The in situ gelled DOL anchored in the tandem framework ensured nice interfacial contact between the as-prepared CPET and electrodes. The introduction of the porous 3D LATP endowed CPET the increased lithium-ion migration number (tLi+) of 0.70, a wide electrochemical stability window (ESW) of 4.86 V, and a high ionic conductivity of 1.16 × 10–4S cm–1at room temperature (RT). Meanwhile, the side reaction of the LATP/Li metal was adequately restrained by inserting TF4030 between the porous LATP and Li anode. Profiting from the superb interfacial stability and the enhanced ionic transport capacity of CPET, Li/Li batteries based on the optimal CPET (CPET2) cycled over 2000 h at 20∼30 °C smoothly. Moreover, solid-state LiFePO4(LFP)/Li with CPET2 exhibited excellent electrochemical performance with a capacity retention ratio of 72.2% after 400 cycles at 0.5C. This work offers an integrated strategy to guide the fabrication of a highly conductive solid electrolyte and a stable interface design for high-performance SSLMBs.

A novel direct Z-scheme CoTiO3/g-C3N4(CT-U) photocatalytic system with different weight percentage of CoTiO3was synthesized using a facile in situ growth method for H2evolution from water splitting. The as-prepared CT-U composites composed of 1D CoTiO3microrod and 2D g-C3N4nanosheet were characterized by various techniques including XRD, SEM, TEM, XPS, FTIR, and UV–vis. Results demonstrate that the CT-U composite photocatalysts were successfully fabricated, with intimate interfacial contact and heterojunction interaction between g-C3N4and CoTiO3which can significantly boost the photocatalytic activity compared with prinstine g-C3N4and CoTiO3. The most enhanced H2-evolution rate of 858 μmol h–1g–1and high quantum efficiency (38.4% at 365 nm, 3.23% at 420 ± 20 nm) are achieved at an optimal 0.15% CT-U. Meanwhile, the 0.15% CT-U sample exhibits good photocatalytic stability in recycling H2evolution. Accordingly, direct Z-scheme mechanism capable of leading efficient charge carrier separation and strong reduction ability for enhanced H2production was proposed, and further evidenced by PL, photoelectrochemical analysis, and ESR assay.