RSC Advances

Phan, Nga Hang Thi; Nguyen, Chinh Chien; Dinh, Minh Tuan Nguyen

doi: 10.1039/d3ra00957bpmid: 37143917

In this study, a novel glucose-assisted redox hydrothermal method has been presented to prepare an Mn-doped CeO2 catalyst (denoted as Mn-CeO2-R) for the first time. The obtained catalyst contains uniform nanoparticles with a small crystallite size, a large mesopore volume, and rich active surface oxygen species. Such features collectively contribute to improving the catalytic activity for the total catalytic oxidation of methanol (CH3OH) and formaldehyde (HCHO). Interestingly, the large mesopore volume feature of the Mn-CeO2-R samples could be considered an essential factor to eliminate the diffusion limit, favoring the total oxidation of toluene (C7H8) at high conversion. Therefore, the Mn-CeO2-R catalyst outperforms both bare CeO2 and conventional Mn-CeO2 catalysts with T90 values of 150 °C and 178 °C for HCHO and CH3OH, respectively, and 315 °C for C7H8, at a high GHSV of 60 000 mL g−1 h−1. Such robust catalytic activities signify a potential utilization of Mn-CeO2-R for the catalytic oxidation of volatile organic compounds (VOCs).

Wang, Rui; Cao, Jingwen; Xu, Chunyu; Wu, Ningning; Zhang, Shu; Wu, Mengqiang

doi: 10.1039/d3ra01111apmid: 37143919

Silicon-based anode materials have been applied in lithium-ion batteries with high energy density. However, developing electrolytes that can meet the specific requirements of these batteries at low temperatures still remains a challenge. Herein, we report the effect of linear carboxylic ester ethyl propionate (EP), as the co-solvent in a carbonate-based electrolyte, on SiOx/graphite (SiOC) composite anodes. Using electrolytes with EP, the anode provides better electrochemical performance at both low temperatures and ambient temperature, showing a capacity of 680.31 mA h g−1 at −50 °C and 0.1C (63.66% retention relative to that at 25 °C), and a capacity retention of 97.02% after 100 cycles at 25 °C and 0.5C. Within the EP-containing electrolyte, SiOC‖LiCoO2 full cells also exhibit superior cycling stability at −20 °C for 200 cycles. These substantial improvements of the EP co-solvent at low temperatures are probably due to its involvement to form a solid electrolyte interphase with high integrity and facile transport kinetics in electrochemical processes.

Asl, Aref Mahmoudi; Karami, Bahador; Karimi, Zahra

doi: 10.1039/d3ra00804epmid: 37143914

In this study, tungstic acid immobilized on polycalix[4]resorcinarene, PC4RA@SiPr–OWO3H, as a mesoporous acidic solid catalyst was synthesized and investigated for its catalytic activity. Polycalix[4]resorcinarene was prepared via a reaction between formaldehyde and calix[4]resorcinarene, and then the resulting polycalix[4]resorcinarene was modified using (3-chloropropyl)trimethoxysilane (CPTMS) to obtain polycalix[4]resorcinarene@(CH2)3Cl that was finally functionalized with tungstic acid. The designed acidic catalyst was characterized by various methods including FT-IR spectroscopy, energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), elemental mapping analysis and transmission electron microscopy (TEM). The catalyst efficiency was evaluated via the preparation of 4H-pyran derivatives using dimethyl/diethyl acetylenedicarboxylate, malononitrile, and beta-carbonyl compounds, confirmed by FT-IR spectroscopy and 1H and 13C NMR spectroscopy. The synthetic catalyst was introduced as a suitable catalyst with high recycling power in 4H-pyran synthesis.

Warman, Harry; Slocombe, Louie; Sacchi, Marco

doi: 10.1039/d3ra00983apmid: 37143915

Hachimoji DNA is a synthetic nucleic acid extension of DNA, formed by an additional four bases, Z, P, S, and B, that can encode information and sustain Darwinian evolution. In this paper, we aim to look into the properties of hachimoji DNA and investigate the probability of proton transfer between the bases, resulting in base mismatch under replication. First, we present a proton transfer mechanism for hachimoji DNA, analogous to the one presented by Löwdin years prior. Then, we use density functional theory to calculate proton transfer rates, tunnelling factors and the kinetic isotope effect in hachimoji DNA. We determined that the reaction barriers are sufficiently low that proton transfer is likely to occur even at biological temperatures. Furthermore, the rates of proton transfer of hachimoji DNA are much faster than in Watson–Crick DNA due to the barrier for Z–P and S–B being 30% lower than in G–C and A–T. Suggesting that proton transfer occurs more frequently in hachimoji DNA than canonical DNA, potentially leading to a higher mutation rate.

Wu, Hao; Fu, Yanlin; Dong, Wenrui; Fu, Bina; Zhang, Dong H.

doi: 10.1039/d3ra02069jpmid: 37143908

An accurate global full-dimensional machine learning-based potential energy surface (PES) of the simplest Criegee intermediate (CH2OO) reaction with water monomer was developed based on the high level of extensive CCSD(T)-F12a/aug-cc-pVTZ calculations. This analytical global PES not only covers the regions of reactants to hydroxymethyl hydroperoxide (HMHP) intermediates, but also different end product channels, which facilities both the reliable and efficient kinetics and dynamics calculations. The rate coefficients calculated by the transition state theory with the interface to the full-dimensional PES agree well with the experimental results, indicating the accuracy of the current PES. Extensive quasi-classical trajectory (QCT) calculations were performed both from the bimolecular reaction CH2OO + H2O and from HMHP intermediate on the new PES. The product branching ratios of hydroxymethoxy radical (HOCH2O, HMO) + OH radical, formaldehyde (CH2O) + H2O2 and formic acid (HCOOH) + H2O were calculated. The reaction yields dominantly HMO + OH, because of the barrierless pathway from HMHP to this channel. The computed dynamical results for this product channel show the total available energy was deposited into the internal rovibrational excitation of HMO, and the energy release in OH and translational energy is limited. The large amount of OH radical found in the current study implies that the CH2OO + H2O reaction can provide crucially OH yield in Earth's atmosphere.

Xu, Xiao-yu; Xu, Zheng; Wang, Li-ding; Wang, Xiao-dong; Sun, Zhong-ping; Yu, Yu

doi: 10.1039/d3ra01140bpmid: 37143918

The stretching breakup of a conical liquid bridge is the core process of micro-dispensing. To precisely control the droplet loading and improve the dispensing resolution, a detailed study of bridge breakup with a moving contact line is required. A conical liquid bridge is established by an electric field and stretching breakup is investigated here. The effect of contact line state is investigated by examining the pressure at the symmetry axis. Compared to the pinned case, the moving contact line causes a shift of the pressure maximum from the bridge neck to top, and it facilitates the evacuation of the bridge top. For the moving case, factors affecting the contact line motion are then considered. The results show that the increase of the stretching velocity U and the decrease of the initial top radius Rtop accelerate the contact line motion. And the amount of contact line movement is basically constant. To analyze the influence of the moving contact line on bridge breakup, neck evolution is tracked under different U. An increase of U decreases the breakup time and increases the breakup position. Based on the breakup position and the remnant radius, the influences of U and Rtop on remnant volume Vd are examined. It is found that Vd decreases with an increase of U and increases with an increase of Rtop. Accordingly, different sizes of remnant volume can be obtained by adjusting U and Rtop. This is helpful for the optimization of liquid loading for transfer printing.

Liu, Yang; Wang, Yungang; Zou, Li; Bai, Yanyuan; Xiu, Haoran

doi: 10.1039/d3ra01452epmid: 37143916

Walnut shell is characterized by high yield, high fixed carbon content, and low ash content. In this paper, the thermodynamic parameters for walnut shell during the carbonization process is investigated, and its carbonization and mechanism are discussed. Then, the optimal carbonization process of walnut shell is proposed. Results demonstrated that the comprehensive characteristic index of pyrolysis first increases and then decreases with the increase of heating rate and reaches the peak at about 10 °C min−1. Note that the carbonization reaction intensifies at this heating rate. The carbonization process of walnut shell is a complex reaction involving multiple steps. It decomposes hemicellulose, cellulose, and lignin in stages, and the activation energy of this process gradually increases. The simulation and experimental analyses showed that the optimal process presents a heating time of 14.8 min, final temperature of 324.7 °C, holding time of 55.5 min, particle size of material of about 2 mm, and optimum carbonization rate of 69.4%.

Ayoub, Irfan; Kumar, Vijay

doi: 10.1039/d3ra02659kpmid: 37152566

Here, we report a series of white-emitting Ba(La2−xDyx)ZnO5 (x = 0–7 mol%) phosphors synthesized via a high-temperature solid-state reaction. The synthesized phosphor's phase purity and tetragonal crystal structure were confirmed by an X-ray powder diffraction (XRPD) pattern. The wide bandgap characteristic feature was assessed through reflectance spectra, and the estimated bandgap was found to be 4.70 eV. Besides analyzing the effect of doping on the surface morphology, the distribution of ions on the surface was observed through the secondary ion mass spectroscopy technique. The synthesized phosphor was found to display bluish (486 nm) and yellowish (576 nm) bands in the emission spectra under the excitation of 325 nm and 352 nm, which together are responsible for producing the white luminescence. The analysis of Judd–Ofelt parameters indicates the symmetric nature of Dy3+ substitution in the present host. The thermal stability of the phosphor was assessed by varying the temperature up to 403 K, and it was found that the synthesized phosphor possesses improved thermal stability with an activation energy of 0.29 eV. The photometric evaluations of the present phosphor revealed the CIE coordinates around the near-white regime (0.3448, 0.3836), along with the color-correlated temperature value of 5102 K. All research on this luminescent material's unique features points to the possibility of using it to fabricate white-light-emitting devices for solid-state lighting applications.

Ahrestani, Zahra; Sadeghzadeh, Sadegh; Emrooz, Hosein Banna Motejadded

doi: 10.1039/d3ra90037apmid: 37152565

Correction for ‘An overview of atmospheric water harvesting methods, the inevitable path of the future in water supply’ by Zahra Ahrestani et al., RSC Adv., 2023, 13, 10273–10307, https://doi.org/10.1039/D2RA07733G.

Saleem, Qasar; Shahid, Sammia; Rahim, Abdur; Bajaber, Majed A.; Mansoor, Sana; Javed, Mohsin; Iqbal, Shahid; Bahadur, Ali; Aljazzar, Samar O.; Pashameah, Rami Adel; AlSubhi, Samah A.; Alzahrani, Eman; Farouk, Abd-ElAziem

doi: 10.1039/d2ra07847cpmid: 37152558

Catechol is a pollutant that can lead to serious health issues. Identification in aquatic environments is difficult. A highly specific, selective, and sensitive electrochemical biosensor based on a copper-polypyrrole composite and a glassy carbon electrode has been created for catechol detection. The novelty of this newly developed biosensor was tested using electrochemical techniques. The charge and mass transfer functions and partially reversible oxidation kinetics of catechol on the redesigned electrode surface were examined using electrochemical impedance spectroscopy and cyclic voltammetry scan rates. Using cyclic voltammetry, chronoamperometry, and differential pulse voltammetry, the characteristics of sensitivity (8.5699 μA cm−2), LOD (1.52 × 10−7 μM), LOQ (3.52 × 10−5 μM), linear range (0.02–2500 μM), specificity, interference, and real sample detection were investigated. The morphological, structural, and bonding characteristics were investigated using XRD, Raman, FTIR, and SEM. Using an oxidation–reduction technique, a suitable biosensor material was produced. In the presence of interfering compounds, it was shown that it was selective for catechol, like an enzyme.