Bifunctional 2D/2D g-C3N4/BiO2-x nanosheets heterojunction for bacterial disinfection mechanisms under visible and near-infrared light irradiation.

The efficient deployment of visible and near-infrared (NIR) light for photocatalytic disinfection is of great concern a matter. Herein, we report a specific bifunctional 2D/2D g-C3N4/BiO2-x nanosheets heterojunction, prepared through a self-assembly approach. Delightfully, the obtained 2D/2D heterojunctions exhibited satisfactory photocatalytic disinfection performance towards Escherichia coli K-12 (E. coli K-12) under visible light irradiation, which was credited to the Z-scheme interfacial heterojunction facilitating the migration of photogenerated carries. The photoactivity enhancement driven by NIR light illumination was ascribed to the cooperative synergy effect of photothermal effect and "hot electrons", engineering efficient charge transfer. Intriguingly, the carboxyl groups emerged on g-C3N4 nanosheets contributed a vital role in establishing the enhanced photocatalytic reaction. Moreover, the disinfection mechanism was systematically described. The cell membrane was destroyed, evidenced by the generation of lipid peroxidation reaction and loss of energy metabolism. Subsequently, the damage of defense enzymes and release of intracellular constituents announced the irreversible death of E. coli K-12. Interestingly enough, considerable microbial community shifts of surface water were observed after visible and NIR light exposure, highlighting the critical feature of disinfection process in shaping microbial communities. The authors believe that this work gives a fresh light on the feasibility of heterostructures-enabled disinfection processes.

Defect Regulating of Few-Layer Antimonene from Acid-Assisted Exfoliation for Enhanced Electrocatalytic Nitrogen Fixation.

Nitrogen reduction reaction (NRR), as a green and sustainable technology, is far from a practical application due to the lack of efficient electrocatalysts. In this work, we found that antimonene, a group-VA elemental two-dimensional (2D) material, is attractive as an electrocatalyst for NRR. The antimonene here is acquired through chemical exfoliation of antimony (Sb) using H2SO4 for the first time, which simultaneously achieved efficient large-sized exfoliation and created a high density of active edge sites. Moreover, the concentration of defects shows a gradual increasing tendency as the treatment time extends. The obtained antimonene exhibited favorable average ammonia (NH3) yield and Faradaic efficiency as high as 2.08 µg h-1 cm-2 and 14.25% at -0.7 V versus RHE, respectively. Density functional theory calculations prove that the sufficient exposure of edge defects is favorable for reducing the reaction barrier and strengthening the interaction between antimonene and the intermediates of NRR, thus increasing the selectivity and yield rate of NH3. The chemical exfoliation of Sb reported here offers an alternative avenue to engineer the surface structures of group-VA elemental-based catalysts. Investigation of NRR using 2D antimonene can further provide deep insight into the mechanism and principle of NRR over group-VA elemental nanosheets.

Macroscopic urea-functionalized cadmium sulfide material with high visible-light photocatalytic activity for rewritable paper application.

A macroscopic urea-functionalized CdS (CdS-U) is synthesized for the first time. The CdS-U material is formed through the interaction between NH2/NH groups on urea and COO- groups on sodium oleate-capped CdS nanoparticles (CdS-So NPs). The CdS-U material exhibites excellent visible light photocatalytic activity and plasticity and has the potential to be produced as rewritable papers. It is convenience to produce a large-scale film by CdS-U. Letters can be written on the CdS-U film and disappear through a dissolution-irradiation process, and then the CdS-U film can be recycled by drying. This novel CdS-U material might be of interest and provide a new chance to advance the application of visible light photocatalyst on rewritable papers.

The plumbing of land surface models: is poor performance a result of methodology or data quality?

The PALS Land sUrface Model Benchmarking Evaluation pRoject (PLUMBER) illustrated the value of prescribing a priori performance targets in model intercomparisons. It showed that the performance of turbulent energy flux predictions from different land surface models, at a broad range of flux tower sites using common evaluation metrics, was on average worse than relatively simple empirical models. For sensible heat fluxes, all land surface models were outperformed by a linear regression against downward shortwave radiation. For latent heat flux, all land surface models were outperformed by a regression against downward shortwave, surface air temperature and relative humidity. These results are explored here in greater detail and possible causes are investigated. We examine whether particular metrics or sites unduly influence the collated results, whether results change according to time-scale aggregation and whether a lack of energy conservation in flux tower data gives the empirical models an unfair advantage in the intercomparison. We demonstrate that energy conservation in the observational data is not responsible for these results. We also show that the partitioning between sensible and latent heat fluxes in LSMs, rather than the calculation of available energy, is the cause of the original findings. Finally, we present evidence suggesting that the nature of this partitioning problem is likely shared among all contributing LSMs. While we do not find a single candidate explanation for why land surface models perform poorly relative to empirical benchmarks in PLUMBER, we do exclude multiple possible explanations and provide guidance on where future research should focus.