A novel high excited state energy transfer pathway to overcome the phonon quenching effect in rare-earth (RE) oxide upconversion (UC) materials is reported. In Er(Tm)-Yb oxide systems, an extraordinary enhancement of UC luminescence efficiency with four orders of magnitude is realized by Mo co-doping. The RE oxides with significant UC efficiency are successfully utilized for temperature sensing and in vivo imaging.

We have realized in-situ growth of ultrathin ZnIn2S4 nanosheets on the sheet-like g-C3N4 surfaces to construct a “sheet-on-sheet” hierarchical heterostructure. The as-synthesized ZnIn2S4/g-C3N4 heterojunction nanosheets exhibit remarkably enhancement on the photocatalytic activity for H2 production. This enhanced photoactivity is mainly attributed to the efficient interfacial transfer of photoinduced electrons and holes from g-C3N4 to ZnIn2S4 nanosheets, resulting in the decreased charge recombination on g-C3N4 nanosheets and the increased amount of photoinduced charge carriers in ZnIn2S4 nanosheets. Meanwhile, the increased surface-active-sites and extended light absorption of g-C3N4 nanosheets after the decoration of ZnIn2S4 nanosheets may also play a certain role for the enhancement of photocatalytic activity. Further investigations by the surface photovoltage spectroscopy and transient photoluminescence spectroscopy demonstrate that ZnIn2S4/g-C3N4 heterojunction nanosheets considerable boost the charge transfer efficiency, therefore improve the probability of photoinduced charge carriers to reach the photocatalysts surfaces for highly efficient H2 production.

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Liquid-crystal monomers (LCMs), especially fluorinated biphenyls and analogues (FBAs), are considered to be a new generation of persistent, bioaccumulative, and toxic organic pollutants, but their emissions from liquid-crystal display (LCD)-associated e-waste dismantling remain unknown. To fill this knowledge gap, a broad range of 46 LCMs, including 39 FBAs and 7 biphenyls/bicyclohexyls and analogues (BAs), were investigated by a dedicated target analysis in e-waste dust samples. Of 39 target FBAs, 34 were detected in LCD dismantlingassociated dust. Among these 34 detectable FBAs, 9 were detected in 100% of the samples and 25 were frequently detected in >50% of the samples. The total concentrations of these 34 FBAs (∑ 34 FBAs) detected in LCD e-waste dust were in the range of 225−976,000 (median: 18,500) ng/g, significantly higher than those in non-LCD e-waste dust (range: 292−18,500, median: 2300 ng/g). In addition to FBAs, six of seven BAs were also frequently detected in LCD e-waste dust with total concentrations (∑ 6 BAs) of 29.8−269,000 (median: 3470) ng/g. Very strong and significant correlations (P < 0.01) were identified in all frequently detected LCMs, indicating their common applications and similar sources. Our findings demonstrate that e-waste dismantling contributes elevated emissions of FBAs and BAs to the ambient environment.