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A wideband module antenna comprised of a small ground radiation antenna in the module and a parasitic radiation loop in the evaluation board is proposed. Unlike conventional ground radiation antennas, the ground radiation antenna in the module works as an exciter to the parasitic radiation loop, which further couples with the evaluation board as a radiator. Thus, a space‐saving antenna is obtained with wide bandwidth and easy tuning. Accordingly, dual resonance can be generated by tuning the resonant frequencies of the ground radiation antenna and the parasitic radiation loop equally. When measured, the antennas have wide bandwidths (2:1 voltage standing wave ratio bandwidth of 270 MHz) and high efficiency (ranging from 44 to 74%). [ABSTRACT FROM AUTHOR]

[Display omitted] • Pure CeO 2 was applied to hydrogen sensor in the air for the first time. • CeO 2 nanorods were synthesized via hydrothermal method. • CeO 2 nanorods showed enhanced hydrogen sensing performance. In this work, the ceria nanorods (8–12 nm) and nanospheres (100–140 nm) were synthesized by solvothermal method, which were verified by structural characterization techniques. Compared to the nanospheres, the ceria nanorods exhibited enhanced hydrogen gas sensing performance. The optimal operating temperature of ceria was reduced from 150 °C to 100 °C after morphology transformation. The response value of the ceria nanorods toward 1000 ppm hydrogen was 5.32, which was nearly 1.6 times higher than that of nanospheres at 100 °C. The enhanced gas sensing performance could be attributed to its larger specific surface area (21.054 m2/g) and small crystallite size (8–12 nm). [ABSTRACT FROM AUTHOR]

Two ground radiation antennas with polarisation diversity performance were proposed for MIMO WLAN applications in wearable devices. The antennas can simultaneously excite the vertical mode and horizontal mode of the ground plane and the phase difference between the two modes can be controlled by utilising an inductor‐loaded metal strip in the ground plane, generating circular polarisation. A 3:1 VSWR bandwidth of 140 MHz with high isolation (above 17 dB) and a 3 dB axial ratio bandwidth of 100 MHz was obtained. The opposite rotations generated by the two antennas resulted in good diversity performance, which was verified by the measured envelope correlation coefficient. [ABSTRACT FROM AUTHOR]

Abstract In recent years, the favorable effect of oxygen vacancies on photoelectrochemical performance has been observed in various metal oxides except In 2 O 3 and little attention has been paid to the photoelectrochemical properties of hydrogenated In 2 O 3 nanostructures. In this work, oxygen vacancies were introduced into In 2 O 3 nanocubes via hydrogenation. The formation of oxygen vacancies was verified by a variety of characterization techniques. Compared to the pristine In 2 O 3 nanocubes, the hydrogenated In 2 O 3 nanocubes exhibited substantially higher photoelectrochemical performance. The enhanced photoelectrochemical performance of hydrogenated In 2 O 3 nanocubes could be attributed to the increased optical absorption, more donor density and the efficient charge transfer and separation of photo-induced charge carrier derived from oxygen vacancies. Graphical abstract Unlabelled Image Highlights • Oxygen vacancy was produced via hydrogenation. • Hydrogenated In 2 O 3 showed outstanding photoelectrochemical performance. • Correlation between Oxygen vacancy and performance was evaluated. [ABSTRACT FROM AUTHOR]

[Display omitted] • In 2 O 3 -loaded CeO 2 nanorods was applied to hydrogen sensor in the air for the first time. • In 2 O 3 -loaded CeO 2 nanorods exhibited enhanced hydrogen sensing performance. • Enhanced hydrogen sensing performance is due to n-n junction and the larger specific surface area. Hydrogen (H 2) detection sensors based on pure CeO 2 nanorods (NRs) and In 2 O 3 -loaded CeO 2 NRs with different In 2 O 3 contents (5 wt%, 10 wt%, and 15 wt%) were investigated. The crystal phase evolution, morphology features, and response characteristics of the In 2 O 3 -loaded CeO 2 NRs were analyzed in detail using characteristic techniques. Gas sensing results showed that the In 2 O 3 -loaded CeO 2 gas sensors exhibited superior H 2 sensing performances compared with pure CeO 2 NRs under low operating temperature (100 °C). Notably, the gas sensors based on the 10 wt% In 2 O 3 -loaded CeO 2 nanocomposite showed the most refined performance, with response values of 2.79 and 2.43 times higher than those of the pure CeO 2 NRs sensors for 1000 ppm and 4000 ppm H 2 , respectively. The response values exhibited a linear relationship with the detection concentration. Moreover, the In 2 O 3 -loaded CeO 2 gas sensor demonstrated enhanced H 2 selectivity, good recyclability, and long-term stability. Finally, the improved gas sensing mechanism of the In 2 O 3 -loaded CeO 2 gas sensor for H 2 was also proposed. [ABSTRACT FROM AUTHOR]