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Here comes the sun: A conversion efficiency as high as 5.4 % has been achieved on dye‐sensitized ZnO solar cells with photoelectrode films consisting of polydisperse aggregates, compared to 2.4 % for the films with only nanosized crystallites. The aggregation of nanocrystallites with a broad size distribution is effective in enhancing the light‐harvesting efficiency by inducing light scattering within the photoelectrode films.

The structure and function of alpine grassland ecosystems, including their extensive soil carbon stocks, are largely shaped by temperature. The Tibetan Plateau in particular has experienced significant warming over the past 50 y, and this warming trend is projected to intensify in the future. Such climate change will likely alter plant species composition and net primary production (NPP). Here we combined 32 y of observations and monitoring with a manipulative experiment of temperature and precipitation to explore the effects of changing climate on plant community structure and ecosystem function. First, long-term climate warming from 1983 to 2014, which occurred without systematic changes in precipitation, led to higher grass abundance and lower sedge abundance, but did not affect aboveground NPP. Second, an experimental warming experiment conducted over 4 y had no effects on any aspect of NPP, whereas drought manipulation (reducing precipitation by 50%), shifted NPP allocation belowground without affecting total NPP. Third, both experimental warming and drought treatments, supported by a meta-analysis at nine sites across the plateau, increased grass abundance at the expense of biomass of sedges and forbs. This shift in functional group composition led to deeper root systems, which may have enabled plant communities to acquire more water and thus stabilize ecosystem primary production even with a changing climate. Overall, our study demonstrates that shifting plant species composition in response to climate change may have stabilized primary production in this high-elevation ecosystem, but it also caused a shift from aboveground to belowground productivity.

Nanomaterials lie at the heart of the fundamental advances in efficient energy storage/conversion and other types of nanodevices in which the surface process and transport kinetics play determining roles. This review describes some recent developments in the synthesis and characterizations of various vanadium oxide nanostructures including nanowires, nanorolls, nanobelts, and ordered arrays of nanorods, nanotubes, and nanocables for significantly enhanced intercalation properties. The major topic of this article is to highlight the lithium ion intercalation properties of nanostructured vanadium oxides for energy storage as well as other applications in sensors, actuators, and transistors.