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Main group Bi‐based materials have gained popularity as N2 reduction reaction (NRR) photo/electrocatalysts due to their ability to inhibit competitive H2 evolution reactions (HER) and the unique N2 adsorption activities. The introduction of defects in Bi‐based catalysts represents a highly effective strategy for enhancing light absorption, promoting efficient separation of photogenerated carriers, optimizing the activity of free radicals, regulating electronic structure, and improving catalytic performance. In this review, we outline the various applications of state of the defect engineering in Bi‐based catalysts and elucidate the impact of vacancies on NRR performance. In particular, the types of defects, methods of defects tailoring, advanced characterization techniques, as well as the Bi‐based catalysts with abundant defects and their corresponding catalytic behavior in NRR were elucidated in detail. Finally, the main challenges and opportunities for future development of defective Bi‐based NRR catalysts are discussed, which provides a comprehensive theoretical guidance for this field. [ABSTRACT FROM AUTHOR]

Development of highly active and selective electrocatalysts for the reduction of nitrate (NO3–) to ammonia is critical for the production of green ammonia. Herein, we designed and synthesized NiMoO4 nanocubes as an efficient electrocatalyst for nitrate reduction using deep eutectic solvents (DESs) as synthesis media. By constructing Mo and Ni dual-active sites, Mo facilitates NO3– adsorption/association, and Ni acts as an active hydrogen (*H) donating center. The amount and destination of *H can be regulated, which can effectively enhance the activity of the NO3– reduction to NH3 reaction (NO3–RR). The optimized sample possessed excellent NO3–RR activity. An NH3–N selectivity of up to 96.94% and a Faraday efficiency of up to 96.13% can be achieved at −0.4 V in a neutral solution. The catalytic NO3–RR mechanism was also investigated by density functional theory (DFT) calculations. This dual-active site electrocatalyst provides an alternative idea for the synthesis and application of high-performance NO3–RR catalysts. [ABSTRACT FROM AUTHOR]

Designing approaches to synthesizing nanostructure photocatalysts is crucial to boosting applications in photocatalytic H2 production. Herein, a Z-scheme p–n heterojunction for photocatalytic H2 production was designed and constructed by decorating p-type CoP3 quantum dots on n-type CdZnS nanorods. The flower-like CoP3/CdZnS nanorod assembly benefits from light absorption and full contact with the solution. An internal electric field forms at the interface of the p–n junction, which provides a Z-scheme charge transport path for efficient migration and separation of photogenerated charges. In result, the hydrogen production rate of the CoP3/CdZnS p–n junction is 33 times that of CdZnS. The study provided a novel approach to the synthesis of self-assembled nanostructures of quantum dots on nanorod assemblies that have important applications in photocatalysis for energy conversion. [ABSTRACT FROM AUTHOR]

Developing a highly efficient catalyst for the oxygen evolution reaction (OER) is of great significance for its application in electrocatalytic water splitting. Herein, a solid–solid transformation strategy has been developed to construct sulfur-doped Ni0.5Co0.5Fe2O4 spinel porous single-crystal nanosheet arrays on nickel foam (S-NCFO/NF). The single-crystalline nanosheet self-assembled nanostructures can provide fast charge transfer channels. With the effect of S-doping, a distorted/incomplete octahedral structure nanosheet can be formed. The unique porous S-NCFO nanosheets can provide a large number of active sites and sufficiently contact the electrolyte to adsorb OH– and desorb O2. By virtue of the porous single-crystal nanosheet, sulfur-doped spinel structure, and the unique self-assembled nanosheet configurations, the S-NCFO/NF electrode exhibits enhanced OER performance with low overpotentials at 100 mA cm–2 of 300 mV in 1 M KOH and 317 mV in 1 M KOH + 0.5 M NaCl. The synthesis strategy provides insight for the preparation and application of self-assembled nanostructures in electrocatalytic seawater splitting. [ABSTRACT FROM AUTHOR]

The 1.43" hybrid wearable AMOLED display (HWAD) had been developed based on low‐temperature polycrystalline silicon (LTPS) and thin‐film encapsulation (TFE) techniques, which was integrated touch and display functionalities with one driver IC. The 1.43" HWAD border was similar to flexible products, but less than rigid ones above 20%. Meanwhile, the ultra‐thin stack‐up module thickness was also close to that of flexible ones, but reduced about 31.4% compared to traditional rigid display. HWAD utilized a new pixel compensation circuit and a novel compensation algorithm, eventually achieved a flicker indicator FMA value of <3% in 5Hz AOD mode. The logic power consumption of the smart watch in 5Hz AOD model is reduced about 35% compared with the one in 30Hz. The novel HWAD aggregated the advantages of flexible and rigid displays with low process costs. The novel high‐performance HWAD had significant market application prospect. [ABSTRACT FROM AUTHOR]

The channel in the marine environment is a time-varying and space-varying channel. Pulse-truncated continuous wave (PCW) speed measurement is often used in sonar, but the instability effect of PCW signal in the channel limits the effectiveness of speed measurement. Hyperbolic frequency modulation (HFM) signal is insensitive to Doppler; therefore, HFM signals are widely used in ranging and velocity measurement of sonar and radar. However, due to the filtering effect of the marine environment, the HFM signal of a single frequency band may cause excessive transmission loss, and the echo energy may be too weak to detect the target. Based on the analysis of the influence of speed on the distance measurement of HFM signal, a pulse sequence method based on HFM for speed measurement (PHS) is proposed, which uses HFM signals of different frequency bands and pulse widths in the pulse sequence to perform speed measurement. Extensive simulation results show that PHS method not only guarantees the speed measurement but also makes full use of the energy of the HFM sequence to improve the accuracy of the distance measurement. And PHS method is valuable to the practical application of engineering. [ABSTRACT FROM AUTHOR]

Photocatalytic nitrogen reduction reaction (NRR) is a sustainable process for ammonia synthesis under mild conditions. However, photocatalytic NRR activity and are generally limited by inefficient carrier separation and transfer. Therefore, parallel engineering of bulk phase doping and surface coupling is critical to achieving the goal of efficient NRR. In this study, Cl doped BiOBr nanosheet assemblies (BiOBr/Cl) were constructed in delicately designed deep eutectic solvents (DESs), combined with ionothermal methods at low temperatures and Bi 3+ exsolution reduction strategy at high temperatures. The unique liquid state and reducibility of DESs induce the reduction of Bi 3+ and the in situ coupling of Bi quantum dots at the surface of BiOBr/Cl nanosheets along with the construction of Bi-BiOBr/Cl nanosheet assemblies. The experimental results show that Cl doping could reduce the exciton dissociation energy and promote its dissociation to free carriers. Bi quantum dots could form tightly coupled Schottky junction with BiOBr/Cl enabling the efficient and unidirectional transmission of photogenerated electrons from BiOBr/Cl to metal Bi. The formed electron deficient region at Schottky interface promotes the adsorption and activation of N 2 . The hierarchical structure of Bi-BiOBr/Cl nanosheet assembly benefits to providing more N 2 adsorption active sites. The DFT calculation shows that the accumulation of high concentration of active hydrogen in Bi-BiOBr/Cl leads to a significant decrease of energy barrier of the first step hydrogenation of N 2 . Bi-BiOBr/Clis more inclined to adsorb nitrogen for NRR in comparison with H* for hydrogen production. The synergistic effect of Cl doping and Bi coupling result in a high NRR activity of Bi-BiOBr/Cl photocatalyst of 6.67 mmol·g -1 ·h -1 , which was 11.3 times higher than that of initial BiOBr. This study provides a promising strategy for designing highly active NRR photocatalysts with high efficiency carrier dissociation and transport., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Main group Bi-based materials have gained popularity as N 2 reduction reaction (NRR) photo/electrocatalysts due to their ability to inhibit competitive H 2 evolution reactions (HER) and the unique N 2 adsorption activities. The introduction of defects in Bi-based catalysts represents a highly effective strategy for enhancing light absorption, promoting efficient separation of photogenerated carriers, optimizing the activity of free radicals, regulating electronic structure, and improving catalytic performance. In this review, we outline the various applications of state of the defect engineering in Bi-based catalysts and elucidate the impact of vacancies on NRR performance. In particular, the types of defects, methods of defects tailoring, advanced characterization techniques, as well as the Bi-based catalysts with abundant defects and their corresponding catalytic behavior in NRR were elucidated in detail. Finally, the main challenges and opportunities for future development of defective Bi-based NRR catalysts are discussed, which provides a comprehensive theoretical guidance for this field., (© 2024 Wiley-VCH GmbH.)

Photothermal conversion has garnered significant attention due to its potential for efficient energy conversion and application in targeted therapies. However, controlling photothermal properties at the atomic level remains a challenge in current materials synthesis. In this study, we report the synthesis and structural determination of a phosphine and mercaptan co-protected Au 5 Ag 12 (SR) 9 (dppf) 4 (Au5Ag12) nanocluster with an extremely low quantum yield (∼0%). For comparative purposes, we synthesized three alloy nanoclusters of similar size. Notably, Au5Ag12 demonstrates a remarkably superior photothermal conversion performance, significantly outperforming the other clusters. We investigated this variance from both absorption and emission perspectives. This research not only opens new avenues for the application of clusters with extremely low quantum yields, but also provides experimental evidence for understanding the photothermal conversion properties of cluster materials at the atomic level.