Photocatalytic water splitting using semiconductor-based catalysts is a promising avenue to gain H2 fuel from renewable solar energy. Nonetheless, developing earth-abundant and visible-light-responsive photocatalysts for efficient H2 production still remains a huge challenge. In this work, unique two-dimensional hierarchitectures of S-deficient CdS integrated with ultrafine CoP nanocrystals embedding in graphitic N-doped C (CoP-CN) nanosheets are fabricated for the first time. Noticeably, the graphitic CN electron mediator not only enhances the photocatalytic stability of CdS/CoP-CN composites by protecting CoP from external corrosion but also induces the formation of an ohmic junction to boost electron extraction from CdS to CoP efficiently. Meanwhile, the S vacancies in CdS serve as electron traps to further enhance the separation of photogenerated carriers. Such unique CdS/CoP-CN hierarchical hybrid nanosheets exhibited an extraordinary visible-light-induced (λ > 400 nm) photocatalytic H2-evolving performance, delivering a high apparent quantum yield (26.3% at 420 nm) and an excellent H2 generation rate of 54.01 mmol·g–1·h–1, much superior to those of a CdS/CoP Schottky junction, Pt-loaded CdS, and a vast amount of CdS-based photocatalysts ever reported. In addition, the outstanding H2-evolving durability of CdS/CoP-CN composites was verified by cycling and long-term photocatalytic tests. The findings presented here are anticipated to enlighten the rational design and synthesis of highly active photocatalysts with an ohmic junction for application in energy and environment-related domains.

Fine-resolution land cover (LC) products are critical for studies of urban planning, global climate change, the Earth’s energy balance, and the geochemical cycle as fundamental geospatial data products. It is important and urgent to evaluate the performance of the updated global land cover maps. In this study, three widely used LC maps with 30 m spatial resolution (FROM-GLC30-2020, GLC_FCS30, and GlobeLand30) published around 2020 were evaluated in terms of their degree of consistency and accuracy metrics. First, we compared their similarities and difference in the area ratio and spatial patterns over different land cover types. Second, the sample and response protocol was proposed and validation samples were collected. Based on this, the overall accuracy, producer’s accuracy, and user’s accuracy were analyzed. The results revealed that: (1) the consistent areas of the three maps accounted for 65.96% of the total area and that two maps exceeded 75% of it. (2) The dominant land cover types, bare land and grassland, were the most consistent land cover types across the three products. In contrast, the spatial inconsistency of the wetland, shrubland, and built-up areas were relatively high, with the disagreement mainly occurring in the heterogeneous regions. (3) The overall accuracy of the GLC_FCS30 map was the highest with a value of 87.07%, which was followed by GlobeLand30 (85.69%) and FROM-GLC30 (83.49%). Overall, all three of the LC maps were found to be consistent and have a good performance in classification in the arid regions, but their ability to accurately classify specific types varied.

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