掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.1021/acsomega.4c00403

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry (RSC)  

The bandgap of lead-free, non-toxic Cs₃Bi₂Br₉ perovskite material is reduced from 2.54 eV to 1.78 eV by changing the crystal structure to Cs₃Bi_2−xFe_xBr₉, Cs₂Bi_1−xFe_xBr₅, and CsFeBr₄, depending on the varying Fe doping concentrations.

DOI： 10.1039/d4ra04062g

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掲載種別：研究論文（学術雑誌）  

A promising green energy technology, anion exchange membrane fuel cells (AEMFCs) offer several advantages over proton exchange membrane fuel cells (PEMFCs), including lower cost, higher durability, and improved effectiveness. However, the widespread commercialization of AEMFCs has been hindered by the lack of low-cost, high-conductivity anion-exchange membranes (AEMs). This work reports the fabrication of a high-conductivity OH− ion exchange membrane using simple freeze-drying of graphene oxide at pH = 11 (3DGO11). At 25 °C and 100% RH conditions, the resulting membrane exhibits a through-plane hydroxide ion conductivity of 1.93 × 10−4 S cm−1 and an in-plane conductivity of 3.74 × 10−2 S cm−1. This high conductivity is attributed to the high porosity and multi-directional ion transport pathways created by the three-dimensional alkaline graphene oxide structure. These findings suggest a route for the development of cost-effective and high-performance AEMFCs.

DOI： 10.1039/d4ya00059e

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society on Water Environment  

DOI： 10.2965/jwet.23-071

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society on Water Environment  

DOI： 10.2965/jwet.24-044

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this study, we investigated the impact of benzophenone (BP), a small molecule additive, on the performance and stability of inverted perovskite solar cells (PSCs). Specifically, we introduced BP into the perovskite precursor solution of FAPbI3 to fabricate PSCs with an ITO/PEDOT:PSS/BP:FAPbI3/PCBM/C60/PCB/Ag architecture. The incorporation of BP with an optimum concentration of 2 mg mL-1 significantly enhanced the power conversion efficiency (PCE) of the inverted PSC from 13.12 to 18.84% with negligible hysteresis. Notably, the BP-based PSCs retained ∼90% of their initial PCE after being stored in ambient air with 30% relative humidity at 25 °C for 700 h. In contrast, control devices showed rapid degradation, retaining only 30% of their initial value within 300 h under the same conditions. We attributed the superior performance and stability of the BP-based PSCs to the grain boundary passivation of the perovskite film. The improvement was mainly attributed to the intermolecular interaction between the O-donor Lewis base BP material and both Pb2+ and FA+ in FAPbI3. This effectively suppresses trap-assisted recombination and promotes the conversion of the δ-phase to photoactive and stable α-phase FAPbI3. Overall, our findings suggest that BP is a promising additive for improving the performance and stability of inverted PSCs.

DOI： 10.1021/acsami.3c09835

PubMed

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.20710/dojo.94.4_245

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Janus transition metal dichalcogenides (TMDCs), with dissimilar chalcogen atoms on each side of TMDCs, have garnered considerable research attention because of the out-of-plane intrinsic polarization in monolayer TMDCs. Although a plasma process has been proposed for synthesizing Janus TMDCs based on the atomic substitution of surface atoms at room temperature, the formation dynamics and intermediate electronic states have not been completely examined. In this study, we investigated the intermediate state between MoSe2 and Janus MoSeS during plasma processing. Atomic composition analysis and atomic scale structural observations revealed the intermediate partially substituted Janus (PSJ) structure. Combined with theoretical calculations, we successfully clarified the characteristic Raman modes in the intermediate PSJ structure. The PL exhibited discontinuous transitions that could not be explained by the theoretical calculations. These findings will contribute toward understanding the formation process and electronic-state modulation of Janus TMDCs.

DOI： 10.1021/acs.nanolett.3c00972

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Dynamic nuclear polarizing (DNP) technique in nuclear magnetic resonance (NMR) is a powerful tool for a microanalysis. Nevertheless, it has not been applied to analyses of carbon materials such as graphene oxide (GO) and amorphous carbon effectively because of the electroconductivity and microwave absorption of the carbon, which attenuate the enhancement effect of DNP. For this study, we applied DNP-NMR to analyses of surface functional groups on GO and sucrose-derived carbon to evaluate the method. The 1H-13C cross-polarization magic-angle spinning (CP/MAS) DNP-NMR of a GO sample with AMUPol (polarizing agent) showed 2.2-times -enhanced peaks of 13C in epoxide, bonding to hydroxyl group, and in the graphene plane. Signal enhance-ment was raised by AMUPol radicals neighboring the surface functional groups and the graphene planes on GO particles, although attenuation by temperature rise must be considered. Furthermore, additional new peaks assigned to CH3 group on the GO particle surface were highly enhanced and were observed clearly only by the accumulations of 64 scans. For sucrose-derived carbon, DNP-NMR clearly revealed the -OH group on the carbon surface or carbon edge by heat treatment, which was not possible using conventional CP/MAS experiments. Cross Effect was found to be dominant in signal enhancements of the functional groups on GO and sucrose-derived carbon samples, except for the CH3 groups on GO. The CH3 enhancement is ascribed mainly to the Over-hauser effect or solid effect.

DOI： 10.1016/j.carbon.2023.02.010

Web of Science

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掲載種別：研究論文（学術雑誌）  

Phosphorus (P) release from sediment caused eutrophication in Kojima Lake, Japan. The efficiency of iron-added sediment microbial fuel cells (SMFCs) in regulating P release from agricultural drainage sediment was investigated in this study. Surface sediment collected from an agricultural drainage canal flowing into Kojima Lake was mixed with iron oxide (Fe2O3) or amorphous iron oxyhydroxide (FeOOH) at 50 mmol kg−1. A 14.6-cm high acrylic pipe was filled with 80 mL of deionized water after 130 g of sediment was placed. A 3 x 3 cm graphite felt was used for the anode in a dual chamber SMFC, while a carbon rod was used for the cathode. Three treatments: No Fe, Fe2O3, and FeOOH, were operated for 408 h under open or closed circuit conditions. Results showed that FeOOH addition lowered P release from sediment regardless of SMFC operational conditions, suggesting that higher P adsorption by FeOOH may mask the effect of SMFCs. Fe2O3 did not reduce total P concentration in the overlying water. In addition, electricity generation was not enhanced by Fe-added SMFCs. Although SMFCs increased sedimentary redox potential, P release was not suppressed by the SMFC operation, indicating that organic P would be released by SMFCs from P-rich sediment.

DOI： 10.2965/JWET.23-040

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掲載種別：研究論文（国際会議プロシーディングス）  

The main purpose of this research is to convert palm acid oil (PAO) into high quality 2nd generation biodiesel fuel (2ndgen.BDF). In this study, we aim to promote decarboxylation (DCX), decarbonylation (DCN), hydrodeoxygenation (HDO), and catalytic cracking (CC) reactions under low pressure using a fixed bed reactor and a batch reactor. In order to proceed with the desired reaction smoothly, some inexpensive composite base metal catalysts supported on silica gel (SiO2) particles were used. Experiments conducted under atmospheric pressure using a fixed bed reactor showed that the recovery of 2ndgen.BDF was up to 50-60% and the acid number was reduced by 94%. In addition, saturated hydrocarbons of C10-C17 are generated in the main components. On the other hand, experiments with a batch reactor at an initial pressure of 0.1 MPa resulted in up to 93% recovery of 2ndgen.BDF and up to 72% reduction in acid value (AV). C15 and C17 saturated hydrocarbons were found to be the main products, indicating a selective reaction.

Scopus

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1627/jpi.61.59

Scopus

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J-GLOBAL

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J-GLOBAL

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J-GLOBAL

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J-GLOBAL

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