High activity, high stability, and low cost have always been the pursuit of photocatalyst design and development. Herein, a simple method is used to integrate abundant anion vacancies (VS) and cation vacancies (VZn) on the surface of ZnS (M–ZnS), deriving VS and VZn pairs (vacancy pairs), isolated Zn atoms (Zniso), and isolated S atoms (Siso). Abundant surface vacancy defects fully expose and activate the surface atoms, regulate the band structure, and significantly improve the separation of photogenerated carriers. M–ZnS is endowed with high activity, and the average hydrogen production rate of the optimal sample increases to 576.07 μmol·g–1·h–1 (λ > 400 nm). Theoretical simulations indicate that the activated Zn atoms are the dominant active sites via the formation of a Zn–OH bond with H2O. Especially, the strong interactions of electrons in atomic orbitals at vacancy pairs and the introduction of VZn are conducive to high stability. The optimal sample maintains an average hydrogen production rate of 6.59 mmol·g–1·h–1 (300 W Xe lamp) after nine cycles. Hence, this work deepens the understanding of vacancy defects and provides an idea for the design of a stable photocatalyst.

Fully printable, hole-conductor-free, carbon-based perovskite solar cells are attractive and promising for industrial production due to their low cost and high stability. However, the efficiency of this type of device is difficult to improve due to the undesirable interfacial contact during the printing process compared to the spin coating process and the higher recombination ratio than the devices with a hole conductor. Herein, a porous anatase nanocrystal (Nano-TiO2) derived by MIL-125, a type of titanium-based metal–organic frameworks (MOFs), was used as the electron transporting material (ETM). The Nano-TiO2 can be conveniently covered on a substrate by screen-printing and still maintain the cakelike morphology, which is beneficial to large-scale production. Moreover, the cakelike morphology composed of nanocrystals is more favorable for the crystallization of perovskites than commercial TiO2 (P25) and can reduce the recombination of photogenerated electron–hole pairs to improve device performance. The device based on Nano-TiO2 shows a V OC of 0.907 V and a fill factor of 68.14% at the forward scan, which is higher than that of the devices based on P25 (0.853 V and 52.95%). It paves a promising way for carbon-based printable perovskite solar cells.

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Transcription factors that act as positive regulators of gibberellin (GA) biosynthetic genes in plants are not well understood. A nuclear-localized basic leucine zipper transcription factor, ZmGRF, was isolated from maize. The core DNA sequence motif recognized for binding by ZmGRF was CCANNTGGC. ZmGRF overexpression in transgenic Arabidopsis plants promoted flowering, stem elongation, and cell expansion. Chromatin immunoprecipitation assays revealed that ZmGRF bound directly to the cis-element CCANNTGGC in the promoter of the Arabidopsis ent-kaurene oxidase (AtKO1) gene and promoted AtKO1 expression. GA4 content increased by 372-567% in transgenic Arabidopsis plants overexpressing ZmGRF compared to wild-type control plants. The GIBBERELLIN-INSENSITIVE DWARF1 gene, which encodes a GA receptor, was also upregulated and the growth-repressing DELLA protein gene GA INSENSITIVE was downregulated. Our results showed ZmGRF functioned through the GA-signaling pathway.

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