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The conversion of water current to voltage generation through graphene has gained interest in both basic physics and applications such as sensors and electricity generation systems. However, many aspects of the mechanism remain unclear. Recently, quantum-based momentum transfer theories have been reported, but these often do not account for flow conditions. In this study, we investigated the correlation between the flow conditions of a liquid medium and the electrical conduction of graphene through experiments and numerical calculations. Our results suggest that the necessary condition is that the flow must be neither irregular nor purely laminar; instead, graphene responds to the transition process of the fluid. This finding supports the extension of current theories and presents valuable insights for both basic science and industrial applications. [ABSTRACT FROM AUTHOR]

Layered double hydroxide (LDH) is considered a highly promising electrode material for supercapacitors (SCs) due to its high theoretical specific capacitance. However, LDH powders often suffer from poor electrical conductivity, structure pulverization, slow charge transport, and insufficient active sites. Herein, a self‐supporting electrode with a Mott–Schottky heterostructure has been designed for high‐performance SCs. The electrode consists of low crystallinity NiCo‐LDH nanosheets and vertical graphene (VG) directly grown on carbon cloth. The LDH was converted from a metal–organic framework (MOF) by the sol–gel method. This self‐supporting electrode provides fast charge transfer, reducing the pulverization effect and energy barrier. The Mott–Schottky heterostructure of LDH@VG regulates electron density and enhances electron transfer, as confirmed by density functional theory calculation. The optimized LDH@VG heterostructure electrode exhibits an excellent areal capacitance of 5513.8 mF cm−2 and rate capability of 82.1%. Furthermore, the fabricated hybrid SC demonstrates excellent energy density of 404.8 μWh cm−2 at 1.6 mW cm−2 and a remarkable cycling life, with a capacitance of 92.0% after 10 000 cycles. This work not only provides a simple dip‐coating and MOF conversion method to synthesize heterojunction‐based electrodes, but also broadens the horizon for designing advanced electrode materials for SCs. [ABSTRACT FROM AUTHOR]

Due to its suitable bandgap and excellent stability, 3C-SiC is being investigated as one of the promising candidates for photoelectrochemical (PEC) water oxidation. However, the limited surface activity and short carrier lifetime prevent 3C-SiC photoanodes from facilitating efficient PEC water splitting. To tackle these problems, this work proposes a plasma technique to control the crystal structure and optical characteristics of 3C-SiC. Nitrogen plasma induces carbon vacancies (Vc) and Si–N bonds, further leading to a narrower bandgap of 3C-SiC. The combination of Vc and N doping enhanced the light trapping capability of the electrode, thereby improving the efficiency of electron–hole pair separation and charge transfer, resulting in an accelerated water oxidation reaction, i.e., photocurrent density (2.50 mA cm−2 at 1.23 VRHE) increased by 7.6 times compared to that of pristine SiC. This work offers an effective strategy for regulating the electronic structure of SiC-based photoanodes by plasma treatment, which may be extended to other photoelectrodes for PEC application. [ABSTRACT FROM AUTHOR]

Abstract The outbreak of coronavirus disease 2019 has seriously threatened human health. Rapidly and sensitively detecting SARS-CoV-2 viruses can help control the spread of viruses. However, it is an arduous challenge to apply semiconductor-based substrates for virus SERS detection due to their poor sensitivity. Therefore, it is worthwhile to search novel semiconductor-based substrates with excellent SERS sensitivity. Herein we report, for the first time, Nb2C and Ta2C MXenes exhibit a remarkable SERS enhancement, which is synergistically enabled by the charge transfer resonance enhancement and electromagnetic enhancement. Their SERS sensitivity is optimized to 3.0 × 106 and 1.4 × 106 under the optimal resonance excitation wavelength of 532 nm. Additionally, remarkable SERS sensitivity endows Ta2C MXenes with capability to sensitively detect and accurately identify the SARS-CoV-2 spike protein. Moreover, its detection limit is as low as 5 × 10−9 M, which is beneficial to achieve real-time monitoring and early warning of novel coronavirus. This research not only provides helpful theoretical guidance for exploring other novel SERS-active semiconductor-based materials but also provides a potential candidate for the practical applications of SERS technology.

Bamboo has become a new trend or focus point as a source of biomass energy in which its proper application is believed to generate the electricity with near-zero waste. ASEAN countries especially have an abundant amount of bamboo that has been use for decades in various applications through their civilization. This study aims to determine the feasibility of bamboo as a renewable energy resource in Malaysia, Indonesia, Vietnam and Japan. This paper reviews general biomass bamboo, availability, and methods of technology in the respective countries based on the review of publication papers and country reports. This fast-growing crop is identical for biomass production as it rapidly self-propagates. Bamboo requires minimum maintenance to grow and is always accessible to be harvested. The woody nature of the tropical bamboo stem contributes to its high calorific value in the form of energy. It was found that Indonesia had become a leading country in generating renewable energy via biomass bamboo through a power plant with a capacity of 700 kW off-grid in Mentawai, Japan with a power generation capacity of 995 kW and Malaysia with 4 MW, will be commercialised by 2023 and 2022. In conclusion, biomass bamboo has great potential for renewable energy generation within these countries. This has consequently contributed to increase in the value of bamboos while positively impacting the socioeconomic stance of the community.

Portable power supplies, particularly lithium‐ion batteries (LIBs), will play a key role in achieving sustainable development goals, and electrode active materials for the next generation of LIBs with higher energy density and longer life time is highly demanded. For this, in situ visualization of Li behavior during the charge/discharge process is essential, and transmission electron microscopy (TEM) will be promising for this purpose. Here, a quite simple experimental setup consisting of a newly developed Li–C nanocomposite film sputter‐deposited onto Au nanoprotrusions at room temperature and graphene synthesized on a W probe at 500 °C for the in situ TEM observation of the battery reaction is proposed. The preservation of the metallic Li in the Li–C film that is transferred to TEM without using any transfer vessels under atmospheric conditions is confirmed by high resolution TEM before the in situ electrochemical process in TEM. After the one cycle of the in situ electrochemical process, the intercalation of Li ions into graphene (lithiation) is clearly observed. Thus, it is concluded that the metallic Li stored in the Li–C film works well as the anode active material in the electrochemical process for solid state LIBs, implying the developed in situ experimental system is promising. [ABSTRACT FROM AUTHOR]