RSC Advances

Bonomi, Sara; Patrini, Maddalena; Bongiovanni, Giovanni; Malavasi, Lorenzo

doi: 10.1039/d0ra04680apmid: 35520057

We report on the successful application of RF-magnetron sputtering to deposit, by using a single type of target, three different materials in the form of thin films within the Cs–Sn–Br compositional range, namely, CsSnBr3, CsSn2Br5 and Cs2SnBr6. It is shown that, by playing with the deposition parameters and post-deposition treatments, it is possible to stabilize these three perovskites or perovskite related compounds by exploiting the versatility of vapor phase deposition. Full characterization in terms of crystal structure, optical properties and morphology is reported. The power of vapor phase methods in growing all-inorganic materials of interest for photovoltaic and optoelectronic applications is demonstrated here, indicating the advantageous use of sputtering for these complex materials.

Rejinold, N. Sanoj; Thomas, Reju George; Muthiah, Muthunarayanan; Chennazhi, K. P.; Park, In-Kyu; Jeong, Yong Yeon; Manzoor, K.; Jayakumar, R.

doi: 10.1039/d0ra90082fpmid: 35532389

Retraction of ‘Radio frequency triggered curcumin delivery from thermo and pH responsive nanoparticles containing gold nanoparticles and its in vivo localization studies in an orthotopic breast tumor model’ by N. Sanoj Rejinold et al., RSC Adv., 2014, 4, 39408–39427, DOI: 10.1039/C4RA05727A.

Pazin, W. M.; Almeida, A. K. A.; Manzoni, V.; Dias, J. M. M.; de Abreu, A. C. F.; Navarro, M.; Ito, A. S.; Ribeiro, A. S.; de Oliveira, I. N.

doi: 10.1039/d0ra05949hpmid: 35520094

Environmental conditions have a profound effect on the photophysical behavior of highly conjugated compounds, which can be exploited in a large variety of applications. In this context, we use a combination of experimental and computational methods to investigate thermal and solvatochromic effects on the fluorescence properties of a dansyl derivative bearing a thienyl substituent, namely 2-(3-thienyl)ethyl dansylglycinate (TEDG). In particular, we analyze how the solvent polarity and temperature affect the ground and excited state energies of TEDG by using time-resolved and steady-state fluorescence techniques. We determine the changes in dipole moment of the TEDG molecule upon photoexcitation, as well as the solvent polarity effects on the excited state lifetime. Besides, we provide theoretical modeling of the HOMO–LUMO orbitals and the vertical absorption and emission energies using time-dependent density functional theory (TDDFT) as well as the polarizable continuum model (PCM) to include the solvent contribution to the absorption and emission energies. Our results show that the emission mechanism of TEDG involves locally excited states derived from hybrid molecular orbitals, accompanied by a moderate variation of the molecular dipole moment upon light excitation. Our findings demonstrate that TEDG exhibits desirable fluorescence properties that make it a promising candidate for use as a photoactive material in electrochromic, optical thermometry, and thermography applications.

Burungale, V. V.; Bae, Hyojung; Kamble, A. S.; Kim, J.-H.; Patil, P. S.; Ha, J.-S.

doi: 10.1039/d0ra04744apmid: 35520089

Carbon doping from a Ti precursor in TiO2 synthesized by a hydrothermal method was studied. The structural, optical and morphological study of the deposited material was carried out using X-ray diffraction, UV-vis spectroscopy and scanning electron microscopy characterization techniques. The elemental composition of the TiO2 deposited with different precursor concentrations was studied using X-ray photoelectron spectroscopy and electron dispersive X-ray spectroscopy. The amount of elemental carbon in the TiO2 matrix is found to be increased as the Ti precursor concentration is increased, which strengthens the proposed idea of carbon doping via a Ti precursor.

Hu, Yang; Jin, Yurong; Zhang, Guangbiao; Yan, Yuli

doi: 10.1039/d0ra04984kpmid: 35520033

We investigate the transport properties of bulk Ca2YZ (Y = Au, Hg; Z = As, Sb, Bi, Sn and Pb) by a combination method of first-principles and Boltzmann transport theory. The focus of this article is the systematic study of the thermoelectric properties under the effect of a spin–orbit coupling. The highest dimensionless figure of merit (ZT) of Ca2AuAs at optimum carrier concentration are 1.23 at 700 K. Interestingly enough, for n-type Ca2HgPb, the maximum ZT are close to each other from 500 K to 900 K and these values are close to 1, which suggests that semimetallic material can also be used as an excellent candidate for thermoelectric materials. From another viewpoint, at room temperature, the maximum PF for Ca2YZ are greater than 3 mW m−1 K−2, which is very close to that of ∼3 mW m−1 K−2 for Bi2Te3 and ∼4 mW m−1 K−2 for Fe2VAl. However, the room temperature theoretical κl of Ca2YZ is only about 0.85–1.6 W m−1 K−1, which is comparing to 1.4 W m−1 K−1 for Bi2Te3 and remarkably lower than 28 W m−1 K−1 for Fe2VAl at same temperature. So Ca2YZ should be a new type of promising thermoelectric material at room temperature.

Liang, Liping; Cheng, Liubiao; Zhang, Yuting; Wang, Qian; Wu, Qian; Xue, Yuanyuan; Meng, Xu

doi: 10.1039/d0ra03125apmid: 35520040

Based on the Fe0/H2O2 heterogeneous Fenton system, the degradation of rhodamine B (RhB, an organic dye pollutant) was researched in this paper. The effects of initial pH value, concentration of H2O2, dosage of zero-valent iron (ZVI), and initial RhB concentration on RhB degradation by Fe0/H2O2 were studied. The results showed that when the initial pH = 4, dosage of ZVI was 9 mM, and concentrations of H2O2 and RhB were 8 mM and 0.1 mM, respectively, the color of RhB could be completely faded within 30 min, and the total organic carbon (TOC) removal percentage was about 63% after 120 min. The dissolved oxygen (DO) content and oxidation–reduction potential (ORP) were monitored during the reaction. Quenching experiments with methanol confirmed that the degradation of the dye was mainly due to oxidation by the ˙OH radical. Besides, the results from UV-Vis spectroscopy showed that the degradation of RhB was mainly due to the destruction of the conjugated oxygen hetero-anthracene in the RhB molecule. The solid-phase characterization of the ZVI samples after reaction confirmed that the original regular and slippery ZVI samples finally were corroded into rough and irregular lepidocrocite and magnetite. Two possible competitive reaction pathways for the degradation of RhB by Fe0/H2O2 were proposed by GC-MS analysis, which were attributed to the dissociation of ethyl radicals and the degradation of chromophore radicals.

Akiyoshi, Kazutaka; Kameyama, Tatsuya; Yamamoto, Takahisa; Kuwabata, Susumu; Tatsuma, Tetsu; Torimoto, Tsukasa

doi: 10.1039/d0ra05165apmid: 35520071

Nanoparticles composed of molybdenum oxide, MoOx, were successfully prepared by room-temperature ionic liquid (RTIL)/metal sputtering followed by heat treatment. Hydroxyl groups in RTIL molecules retarded the coalescence between MoOx NPs during heat treatment at 473 K in air, while the oxidation state of Mo species in MoOx nanoparticles (NPs) could be modified by changing the heat treatment time. An LSPR peak was observed at 840 nm in the near-IR region for MoOx NPs of 55 nm or larger in size that were annealed in a hydroxyl-functionalized RTIL. Photoexcitation of the LSPR peak of MoOx NPs induced electron transfer from NPs to ITO electrodes.

Liu, Guoquan; Li, Fei; Zhu, Yong; Li, Jiayuan; Sun, Licheng

doi: 10.1039/d0ra01961epmid: 35520082

A facile electrodeposition method was developed to prepare Co-BiVO4 thin films with rich oxygen vacancies. The resulting photoanode exhibited a photocurrent density of 3.5 mA cm−2 1.23 V (vs. reversible hydrogen electrode (RHE), AM 1.5 G), which is over two times higher than that of undoped BiVO4.

Peng, Shigui; He, Min; Yang, Zhao; Zhang, Kai; Xue, Bin; Qin, Shuhao; Yu, Jie; Xu, Guomin

doi: 10.1039/d0ra04790bpmid: 35520035

In this work, we creatively obtained reinforced and toughened PC/PMMA/GNs composites by tuning the migration and selective location of graphene nanosheets (GNs) during melt blending. TEM results revealed that the migration of GNs in PC/PMMA blends during melt blending always existed no matter how the GNs were introduced, and most of them exclusively localized at the interface of PC and PMMA phase due to interfacial effects. The migration of GNs could refine the size of the dispersed phase, and the exclusive localization of GNs at the interface show obvious interfacial compatibilizing effects, leading to improved mechanical properties of the composites. It was found that the composite prepared by one-step compounding showed significant enhanced strength and toughness with addition of mere 0.05 wt% GNs and the tensile strength and elongation of the composite increased by about 62.96% and 94.54%, respectively as compared to the PC/PMMA blends. Moreover, the composite prepared by one-step compounding also showed improved thermal conductivity at the same time, indicating excellent comprehensive properties. It is believed that tuning the migration and selective localization of GNs open perspectives for the development of high-performance polymer composites.

Qiao, Hongwei; Bai, Jiakun; Zhang, Sichun; Li, Chao

doi: 10.1039/d0ra05254jpmid: 35520041

Guanosine-based supramolecular hydrogels are particularly of interest for biomaterial and biomedical purposes, as they are generally biocompatible and stimuli-responsive. We found a strong and long-life transparent hydrogel made by mixing guanosine (G) with 1 equiv. of 2-formylbenzeneboronic acid (2FPB) and KOH. Alkali cations can assist the stacking of individual G-quartet to give extended nanowires, but only K+ ion induces the formation of a stable and self-supporting network hydrogel for a couple of months. Data from variable temperature NMR indicated that guanosine 2-formylbenzeneborate ester and G are the key components of the self-assembly. Further, G-2FPB-K+ hydrogel solution can induce berberine (BBR) fluorescence, showing high selectivity to K+ ion and anti-ion interference capability. A good linear relationship between fluorescent intensity and K+ concentration allowed us to directly detect K+ levels in human blood serum.