Incorporating oxophilic metals into noble metal-based catalysts represents an emerging strategy to improve the catalytic performance of electrocatalysts in fuel cells. However, effects of the distance between the noble metal and oxophilic metal active sites on the catalytic performance have rarely been investigated. Herein, we report on ultrasmall (∼5 nm) Pd–Ni–P ternary nanoparticles for ethanol electrooxidation. The activity is improved up to 4.95 A per mgPd, which is 6.88 times higher than commercial Pd/C (0.72 A per mgPd), by shortening the distance between Pd and Ni active sites, achieved through shape transformation from Pd/Ni–P heterodimers into Pd–Ni–P nanoparticles and tuning the Ni/Pd atomic ratio to 1:1. Density functional theory calculations reveal that the improved activity and stability stems from the promoted production of free OH radicals (on Ni active sites) which facilitate the oxidative removal of carbonaceous poison and combination with CH3CO radicals on adjacent Pd active sites.

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One‐dimensional anodic titanium oxide (ATO) nanotube arrays hold great potential as electrode materials for both dye‐sensitized solar cells (DSSCs) and electrochemical supercapacitors (SCs). In this work, a novel stack‐integrated photo‐supercapacitor (PSC) thin‐film device is presented, composed of a DSSC and a SC built on bi‐polar ATO nanotube arrays, where an improved SC performance is achieved through selective plasma‐assisted hydrogenation treatment. At a high current density of 1 mA/cm2 in charge/discharge measurements, the areal capacitance of selective hydrogenated ATO two‐electrode sub‐device is substantially increased ∼5.1 times, with the value as high as 1.100 mF/cm2. The optimized PSC exhibits a remarkable overall photoelectric conversion and storage efficiency up to 1.64%, with fast response and superior cycling capability for more than 100 photocharge/galvanostatic discharge cycles without any decay. To meet applicable demands with a larger output voltage, a tandem PSC system is constructed, serving as the self‐driven power source for an LED.

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Performance of thin film photovoltaics largely relies on photon absorption capability. Here, we introduce a novel substrate with patterned aluminum nanodent arrays with unique light management capability. Hydrogenated amorphous silicon thin film solar cells have been fabricated on the nano-texturized substrate for optical property study and photovoltaic performance evaluation. Our measurements have shown significant enhancement on broadband light absorption using these patterned substrates via both geometrical light trapping and plasmonic coupling. Particularly, the enhancement factor reaches as high as 5-30 times at wavelength near the band edge. Numerical simulations confirm the measurements and uncover the mechanisms of the enhancement. More importantly, photovoltaic measurements on nanodent solar cells present improvements of over 31% and 27% in short circuit current and energy conversion efficiency respectively compared with planar solar cells. Therefore, the novel patterned substrates are promising candidates for low cost and high performance thin film solar cells. Broader contextAmong various alternative energy sources, solar power is of great advantage over other candidates due to its abundance and environmental friendliness. Current solar cells still cannot satisfy people's expectation on performance and cost. Aiming at promoting the ability of harvesting solar power as well as reducing the manufacturing cost, a novel plasmonic substrate was developed using a convenient anodization method for thin lm amorphous silicon solar cells, which convert solar power into electricity within a very thin absorbing layer. According to experimental and nite-difference time-domain simulations, the devices exhibit impressive light trapping capability, due to the coupling of waveguide modes and surface plasmon resonances with the aid of nanoscale patterns. The optimized device conguration delivered 5-30 times absorption enhancement near the band edge. The optical absorption and propagation were systematically investigated in view of photonic guided modes and surface plasmon resonances as well as their coupling effects. In comparison to the device on planar substrates, the plasmonic solar cells achieved signicantly increased short circuit current (31%) with a promising energy conversion efficiency up to 7.11%.

One-dimensional anodic titanium oxide (ATO) nanotube arrays hold great potential as photoanode for photoelectrochemical (PEC) water splitting. In this work, we report a facile and eco-friendly electrochemical hydrogenation method to modify the electronic and PEC properties of ATO nanotube films. The hydrogenated ATO (ATO-H) electrodes present a significantly improved photocurrent of 0.65 mA/cm2 in comparison with that of pristine ATO nanotubes (0.29 mA/cm2) recorded under air mass 1.5 global illumination. The incident photon-to-current efficiency measurement suggests that the enhanced photocurrent of ATO-H nanotubes is mainly ascribed to the improved photoactivity in the UV region. We propose that the electrochemical hydrogenation induced surface oxygen vacancies contribute to the substantially enhanced electrical conductivity and photoactivity.

Thin film photovoltaic (PV) technologies are highly attractive for low-cost solar energy conversion and possess a wide range of potential applications from building-integrated PV generation to portable power sources. Inverted nanocones (i-cones) have been demonstrated as a promising structure for practical thin film PV devices/modules, owning to their antireflection effect, self-cleaning function, superior mechanical robustness, and so forth. In this work, we have demonstrated a low-cost and scalable approach to achieve perfectly ordered i-cone arrays. Thereafter, thin film amorphous silicon (a-Si:H) solar cells have been fabricated based on various i-cone substrates with different aspect ratios and pitches to investigate the impact of geometry of i-cone nanostructures on the performance of the as-obtained PV devices. Intriguingly, the optical property investigations and device performance characterizations demonstrated that the 0.5-aspect-ratio i-cone-based device performed the best on both light absorption capability and energy conversion efficiency, which is 34% higher than that of the flat counterpart. Moreover, the i-cone-based device enhanced the light absorption and device performance over the flat reference device omnidirectionally. These results demonstrate a viable and convenient route toward scalable fabrication of nanostructures for high-performance thin film PV devices based on a broad range of materials.

One-dimensional anodic titanium oxide (ATO) nanotube arrays hold great potential as electrode materials for high-performance electrochemical supercapacitors. However, their poor electronic conductivity limits their practical applications. Here, we develop a hydrogen (H2) plasma treatment method to greatly improve the electrochemical performance of ATO electrodes. Compared with pristine ATO, the nanotubes treated by H2 plasma illumination (ATO-H) present a rough and amorphous layer at the surface of the nanotubes with simultaneously incorporated Ti(3+) and -OH groups. At a current density of 0.05 mA cm(-2) in charge-discharge measurements, the specific capacitance of the ATO-H electrode has substantially increased ~7.4 times, with a value as high as 7.22 mF cm(-2). Moreover, the novel ATO-H electrode has also exhibited excellent rate capability (6.37 mF cm(-2) at a current density of 2 mA cm(-2)) and cycling performance with no degradation after 10,000 cycles.