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Improving the low charge separation efficiency, poor light absorption capacity, and insufficient active sites of photocatalysts are the important challenges for CO2 photoreduction. In this study, a Mo modified InOOH/In(OH)3 heterojunction with enhanced CO2 reduction efficiency was synthesized in situ by using an In(OH)3 monatomic lamellar material with isolated In atom sites exposed on its surface. And bandgap tuning via the energy levels formed by Mo doping and vacancy defect engineering can simultaneously improve visible light absorption and photogenerated charge separation. The results of experimental characterization and DFT calculation show that the Mo impurity energy levels, O defect energy levels, and surface Mo atoms existing in the InOOH phase can act as an electron transfer ladder in cooperation with the In defect energy levels in the In(OH)3 phase, thereby promoting electron transfer between heterogeneous interfaces. Under visible light irradiation, the evolution rates of CH4 and CO of the Mo modified InOOH/In(OH)3 photocatalyst are more than ∼11 and ∼8 times higher than those of InOOH, respectively. This work provides new insights into the design of the CO2 photoreduction platform through a collaborative strategy of bandgap tuning, transition metal doping, and heterostructure construction. [ABSTRACT FROM AUTHOR]

The effect of rare earth (RE) single atoms on photocatalytic activity is very complex due to its special electronic configuration, which leads to few reports on the RE single atoms. Here, Dy3+ single atom composite photocatalysts are successfully constructed based on both the special role of Dy3+ and the special advantages of CdS/g‐C3N4 heterojunction in the field of photocatalysis. The results show that an efficient way of electron transfer is provided to promote charge separation, and the dual functions of CO2 molecular activation of rare‐earth single atom and 4f levels as electron transport bridge are fully exploited. It is exciting that under visible‐light irradiation, the catalytic performance of CdS:Dy3+/g‐C3N4 is ≈6.9 times higher than that of pure g‐C3N4. The catalytic performance of CdS:Dy3+ and CdS:Dy3+/g‐C3N4 are ≈7 and ≈13.7 times higher than those of pure CdS, respectively. Besides, not all RE ions are suitable for charge transfer bridges, which is not only related to the 4f levels of RE ions but also related to the bandgap structure of CdS and g‐C3N4. The pattern of combining single‐atom catalysis and heterojunction opens up new methods for enhancing photocatalytic activity. [ABSTRACT FROM AUTHOR]

Only when the interfacial charge separation is enhanced and the CO2 activation is improved, can the heterojunction nanocomposite photocatalyst be brought into full play for the CO2 reduction reaction (CO2RR). Here, Er3+ single atom composite photocatalysts were successfully constructed based on both the special role of Er3+ single atoms and the special advantages of the SrTiO3:Er3+/g-C3N4 heterojunction in the field of photocatalysis for the first time. As we expected, the SrTiO3:Er3+/g-C3N4 (22.35 and 16.90 μmol g−1 h−1 for CO and CH4) exhibits about 5 times enhancement in visible-light photocatalytic activity compared to pure g-C3N4 (4.60 and 3.40 μmol g−1 h−1 for CO and CH4). In particular, the photocatalytic performance of SrTiO3:Er3+/g-C3N4 is more than three times higher than that of SrTiO3/g-C3N4. From Er3+ fluorescence quenching measurements, photoelectrochemical studies, transient PL studies and DFT calculations, it is verified that a small fraction of surface doping of Er3+ formed Er single-atoms on SrTiO3 building an energy transfer bridge between the interface of SrTiO3 and g-C3N4, resulting in enhanced interfacial charge separation. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (AC HAADF-STEM) and adsorption energy calculations demonstrated that the exposed Er single-atoms outside the interface on SrTiO3 preferentially activate the adsorbed CO2, leading to the high photoactivity for the CO2RR. A novel enhanced photocatalytic mechanism was proposed, in which Er single-atoms play dual roles of an energy transfer bridge and activating CO2 to promote charge separation. This provides new insights and feasible routes to develop highly efficient photocatalytic materials by engineering rare-earth single-atom doping. [ABSTRACT FROM AUTHOR]

Multifunctional nanomaterials for bioprobe and drug carrier have drawn great attention for their applications in the early monitoring the progression and treatment of cancers. In this work, we have developed new multifunctional water-soluble NaLnF4@MOF-Ln nanocomposites with dual-mode luminescence, which is based on stokes luminescent mesoporous lanthanide metal–organic frameworks (MOFs-Y:Eu3+) and anti-stokes luminescent NaYF4:Tm3+/Yb3+ nanoparticles. The fluorescence mechanism and dynamics are investigated and the applications of these nanocomposites as bioprobes and drug carriers in the cancer imaging and treatment are explored. Our results demonstrate that these nanocomposites with the excellent two-color emission show great potential in drug delivery, cancer cell imaging, and treatment, which are attributed to the unique spatial structure and good biocompatibility characteristics of NaLnF4@MOF-Ln nanocomposites. [ABSTRACT FROM AUTHOR]

Colletotrichum species are notorious for causing anthracnose on many fruits, leading to significant economic losses worldwide. As a model, we functionally characterized cys2-his2 (C 2 H 2 ) zinc finger proteins (CsCZFs) in Colletotrichum scovillei , a major causal agent of pepper fruit anthracnose in many countries. In all, 62 CsCZFs were identified by in silico genomic analysis. Twelve were selected based on their expression profiles to generate targeted deletion mutants for functional investigation. ΔCsczf1 markedly reduced conidiation and constitutive expression of CsCZF1 partially recovered conidiation in an asexual reproduction-defective mutant, ΔCshox2 . Deletion of CsCZF12 , orthologous to the calcineurin-responsive transcription factor Crz1 , impaired autophagy in C. scovillei. ΔCsczf9 was defective in surface recognition, appressorium formation, and suppression of host defenses. CsCZF9 was identified as an essential and novel regulator under the control of the mitogen-activated protein kinase (CsPMK1) in an early step of appressorium development in C. scovillei . This study provides novel insights into CsCZF -mediated regulation of differentiation and pathogenicity in C. scovillei , contributing to understanding the regulatory mechanisms governing fruit anthracnose epidemics.IMPORTANCEThe phytopathogenic fungus Colletotrichum scovillei is known to cause serious anthracnose on chili pepper. However, the molecular mechanism underlying anthracnose caused by this fungus remains largely unknown. Here, we systematically analyzed the functional roles of cys2-his2 zinc finger proteins (CsCZFs) in the dissemination and pathogenic development of this fungus. Our results showed that CsCZF1 plays an important role in conidiation and constitutive expression of CsCZF1 restored conidiation in an asexual reproduction-defective mutant, ΔCshox2 . The CsCZF9, a novel target of the mitogen-activated protein kinase (CsPMK1), is essential for surface recognition to allow appressorium formation and suppression of host defenses in C. scovillei . The CsCZF12, orthologous to the calcineurin-responsive transcription factor Crz1, is involved in the autophagy of C. scovillei . Our findings reveal a comprehensive mechanism underlying CsCZF-mediated regulation of differentiation and pathogenicity of C. scovillei , which contributes to the understanding of fruit anthracnose epidemics and the development of novel strategies for disease management.

It is still challenging to design a stable and efficient catalyst for visible-light CO 2 reduction. Here, Er 3+ single atom composite photocatalysts are successfully constructed based on both the special role of Er 3+ and the special advantages of Zn 2 GeO 4 /g-C 3 N 4 heterojunction in the photocatalysis reduction of CO 2 . Especially, Zn 2 GeO 4 :Er 3+ /g-C 3 N 4 obtained by in situ synthesis is not only more conducive to the tight junction of Zn 2 GeO 4 and g-C 3 N 4 , but also more favorable for g-C 3 N 4 to anchor rare-earth atoms. Under visible-light irradiation, Zn 2 GeO 4 :Er 3+ /g-C 3 N 4 shows more than five times enhancement in the catalytic efficiency compared to that of pure g-C 3 N 4 without any sacrificial agent in the photocatalytic reaction system. A series of theoretical and experimental results show that the charge density around Er, Ge, Zn, and O increases compared with Zn 2 GeO 4 :Er 3+ , while the charge density around C decreases compared with g-C 3 N 4 . These results show that an efficient way of electron transfer is provided to promote charge separation, and the dual functions of CO 2 molecular activation of Er 3+ single atom and 4f levels as electron transport bridge are fully exploited. The pattern of combining single-atom catalysis and heterojunction opens up new methods for enhancing photocatalytic activity., (© 2021 Wiley-VCH GmbH.)

Multifunctional nanomaterials for bioprobe and drug carrier have drawn great attention for their applications in the early monitoring the progression and treatment of cancers. In this work, we have developed new multifunctional water-soluble NaLnF 4 @MOF-Ln nanocomposites with dual-mode luminescence, which is based on stokes luminescent mesoporous lanthanide metal-organic frameworks (MOFs-Y:Eu 3+ ) and anti-stokes luminescent NaYF 4 :Tm 3+ /Yb 3+ nanoparticles. The fluorescence mechanism and dynamics are investigated and the applications of these nanocomposites as bioprobes and drug carriers in the cancer imaging and treatment are explored. Our results demonstrate that these nanocomposites with the excellent two-color emission show great potential in drug delivery, cancer cell imaging, and treatment, which are attributed to the unique spatial structure and good biocompatibility characteristics of NaLnF 4 @MOF-Ln nanocomposites., Competing Interests: The authors declare no conflict of interest.