ACS Materials Au最新文献

{"title":"Fine-Tuning the Photocatalytic Activity of the Anatase {1 0 1} Facet through Dopant-Controlled Reduction of the Spontaneously Present Donor State Density","authors":"Szymon Dudziak*,&nbsp;Jakub Karczewski,&nbsp;Adam Ostrowski,&nbsp;Grzegorz Trykowski,&nbsp;Kostiantyn Nikiforow and Anna Zielińska-Jurek,&nbsp;","doi":"10.1021/acsmaterialsau.4c00008","DOIUrl":"10.1021/acsmaterialsau.4c00008","url":null,"abstract":"<p >The present study highlights the importance of the net density of charge carriers at the ground state on photocatalytic activity of the faceted particles, which can be seen as a highly underexplored problem. To investigate it in detail, we have systematically doped {1 0 1} enclosed anatase nanoparticles with Gd³⁺ ions to manipulate the charge carrier concentration. Furthermore, control experiments using an analogical Nb⁵⁺ doped sample were performed to discuss photocatalytic activity in the increased range of free electrons. Overall results showed significant enhancement of phenol degradation rate and coumarin hydroxylation, together with an increase of the designed Gd/Ti ratio up to 0.5 at. %. Simultaneously, the mineralization efficiency, measured as a TOC reduction, was controlled between the samples. The observed activity enhancement is connected with the controlled decrease of the donor state density within the materials, being the net effect of the spontaneously present defects and introduced dopants, witch reduce hydroxylation and the hole trapping ability of the {1 0 1} facets. This allows to fine-tune multi-/single-electron processes occurring over the prepared samples, leading to clear activity maxima for 4-nitrophenol reduction, H₂O₂ generation, and ·OH formation observed for different donor densities. The optimized material exceeds the activity of the TiO₂ P25 for phenol degradation by 52% (377% after surface normalization), showing its suitable design for water treatment. These results present a promising approach to boost photocatalyst activity as the combined result of the exposed crystal facet and dopant-optimized density of ground-state charge carriers.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 4","pages":"436–449"},"PeriodicalIF":5.7,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.4c00008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140298431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Light- and Solvent-Responsive Bilayer Hydrogel Actuators with Reversible Bending Behaviors","authors":"Gorkem Liman,&nbsp;Esma Mutluturk* and Gokhan Demirel*,&nbsp;","doi":"10.1021/acsmaterialsau.4c00005","DOIUrl":"10.1021/acsmaterialsau.4c00005","url":null,"abstract":"<p >Light-responsive hydrogel systems have gained significant attention due to their unique ability to undergo controlled and reversible swelling behavior in response to light stimuli. Combining light-responsive hydrogels with nonresponsive polymers offers a unique self-folding feature that can be used in soft robotic actuator designs. However, simple formulation of such systems with rapid response time is still a challenging task. Herein, we demonstrate a simple but versatile bilayer polymeric design combining light-responsive spiropyran–polyacrylamide (SP-PAAm) with polyacrylamide (PAAm) hydrogels. The photochromic spiropyran in our polymer design is a closed-ring, hydrophobic compound and turns into an open-ring, hydrophilic merocyanine isomer under light irradiation. The swelling degree of SP-PAAm and PAAm hydrogels was evaluated using LED lights with different wavelengths and solvent media (e.g., water, ethanol, DMF, and DMSO). We observed that SP-PAAm hydrogels reached a swelling ratio of ∼370% with the illumination of the blue LED in the DMF medium. By combining light-responsive SP-PAAm hydrogels with nonresponsive PAAm, a proof-of-concept demonstration was performed to demonstrate the applicability of our fabricated platforms. Although fabricated one-armed bilayer hydrogels possessed self-folding ability with a folding angle of ∼40° in 30 min, the four-armed bilayer platforms demonstrated more efficient and rapid folding behavior and reached a folding angle of ∼75° in ∼15 min. Given their simplicity and efficiency, we believe that such polymeric designs may offer new avenues for the fields of polymeric actuators and soft robotic systems.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 4","pages":"385–392"},"PeriodicalIF":5.7,"publicationDate":"2024-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.4c00005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140204244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Depolymerization of Polyester Fibers with Dimethyl Carbonate-Aided Methanolysis","authors":"Shinji Tanaka*,&nbsp;Maito Koga,&nbsp;Takashi Kuragano,&nbsp;Atsuko Ogawa,&nbsp;Hibiki Ogiwara,&nbsp;Kazuhiko Sato and Yumiko Nakajima*,&nbsp;","doi":"10.1021/acsmaterialsau.3c00091","DOIUrl":"10.1021/acsmaterialsau.3c00091","url":null,"abstract":"<p >Polyester fibers, comprising mostly poly(ethylene terephthalate) with high crystalline content, represent the most commonly produced plastic for ubiquitous textiles, and approximately 60 million tons are manufactured annually worldwide. Considering the social issues of mismanaged waste produced from used textile products, there is an urgent demand for sustainable waste polyester fiber recycling methods. We developed a low-temperature, rapid, and efficient depolymerization method for recycling polyester fibers. By utilizing methanolysis with dimethyl carbonate as a trapping agent for ethylene glycol, depolymerization of polyester fibers from textile products proceeded at 50 °C for 2 h, affording dimethyl terephthalate (DMT) in a &gt;90% yield. This strategy allowed us to depolymerize even practical polyester textiles blended with other fibers to selectively isolate DMT in high yields. This method was also applicable for colored polyester textiles, and analytically pure DMT was isolated via depolymerization and decolorization processes.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 3","pages":"335–345"},"PeriodicalIF":0.0,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.3c00091","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140165870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Celebrating Inclusion and Diversity of Women in Science","authors":"Diana Mancera-Zapata*,&nbsp; and ,&nbsp;Astrid Saldaña,&nbsp;","doi":"10.1021/acsmaterialsau.4c00009","DOIUrl":"https://doi.org/10.1021/acsmaterialsau.4c00009","url":null,"abstract":"","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 2","pages":"107"},"PeriodicalIF":0.0,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.4c00009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140112635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of Electrocoagulated Sewage as a Photoelectrocatalyst for Water Splitting","authors":"Lalita Sharma, Jyoti Rohilla, Pravin P. Ingole, Aditi Halder","doi":"10.1021/acsmaterialsau.4c00006","DOIUrl":"https://doi.org/10.1021/acsmaterialsau.4c00006","url":null,"abstract":"Electrocoagulation (EC) as a wastewater treatment process for the removal of pollutants has been demonstrated in numerous studies. However, proper management of solid waste generated after EC treatment is essential to minimize its environmental impact. Hence, more emphasis needs to be paid towards unused solid waste after EC treatment. The present study investigates the possibilities of utilizing waste released after the EC process as an electrocatalyst in the presence of sunlight. In this study, the sludge produced after domestic wastewater treatment by the EC process is collected and tested for water oxidation reaction under AM 1.5 illumination of simulated solar light. The sludge produced after EC treatment was characterized meticulously and confirmed to be the magnetite phase of iron oxide, which is used as a photoanode for photoelectrochemical (PEC) water splitting. The chemical composition of sludge is majorly dependent on the treatment time, which plays a crucial role in deciding the metal ions present in the sludge. After 30 min, which is the optimized time for EC treatment, sludge was studied as an efficient photoanode material. The band gap illumination of sludge (iron oxide) as working electrodes results in anodic current; the photocurrent appears at a bias of ca. 390 mV with respect to the flat-band potential. The PEC activity of waste is treatment-time dependent and decreases after reaching an optimal time of 30 min. A photocurrent density of 4.6 × 10^–6 A cm^–2 was found at the potential of 1.23 V (vs RHE) for sludge collected after 30 min of treatment time. It indicates that the sludge-derived photoanode has the potential to be an efficient component in PEC systems, contributing to the overall efficiency of water-splitting processes. Our experimental results show a new pathway of a <b>“</b>waste to energy<b>”</b> approach that aligns with the principles of circular economy and sustainable resource management.","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140001429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of Electrocoagulated Sewage as a Photoelectrocatalyst for Water Splitting","authors":"Lalita Sharma,&nbsp;Jyoti Rohilla,&nbsp;Pravin P. Ingole and Aditi Halder*,&nbsp;","doi":"10.1021/acsmaterialsau.4c0000610.1021/acsmaterialsau.4c00006","DOIUrl":"https://doi.org/10.1021/acsmaterialsau.4c00006https://doi.org/10.1021/acsmaterialsau.4c00006","url":null,"abstract":"<p >Electrocoagulation (EC) as a wastewater treatment process for the removal of pollutants has been demonstrated in numerous studies. However, proper management of solid waste generated after EC treatment is essential to minimize its environmental impact. Hence, more emphasis needs to be paid towards unused solid waste after EC treatment. The present study investigates the possibilities of utilizing waste released after the EC process as an electrocatalyst in the presence of sunlight. In this study, the sludge produced after domestic wastewater treatment by the EC process is collected and tested for water oxidation reaction under AM 1.5 illumination of simulated solar light. The sludge produced after EC treatment was characterized meticulously and confirmed to be the magnetite phase of iron oxide, which is used as a photoanode for photoelectrochemical (PEC) water splitting. The chemical composition of sludge is majorly dependent on the treatment time, which plays a crucial role in deciding the metal ions present in the sludge. After 30 min, which is the optimized time for EC treatment, sludge was studied as an efficient photoanode material. The band gap illumination of sludge (iron oxide) as working electrodes results in anodic current; the photocurrent appears at a bias of ca. 390 mV with respect to the flat-band potential. The PEC activity of waste is treatment-time dependent and decreases after reaching an optimal time of 30 min. A photocurrent density of 4.6 × 10^–6 A cm^–2 was found at the potential of 1.23 V (vs RHE) for sludge collected after 30 min of treatment time. It indicates that the sludge-derived photoanode has the potential to be an efficient component in PEC systems, contributing to the overall efficiency of water-splitting processes. Our experimental results show a new pathway of a <b>“</b>waste to energy<b>”</b> approach that aligns with the principles of circular economy and sustainable resource management.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 5","pages":"459–467 459–467"},"PeriodicalIF":5.7,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.4c00006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142161260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiscale Length Structural Investigation and Thermoelectric Performance of Double-Filled Sr0.2Yb0.2Co4Sb12: An Exceptional Thermal Conductivity Reduction by Filler Segregation to the Grain Boundaries","authors":"Federico Serrano-Sanchez,&nbsp;João Elias Rodrigues,&nbsp;Javier Gainza,&nbsp;Catherine Dejoie,&nbsp;Oscar J. Dura,&nbsp;Neven Biskup,&nbsp;Norbert M. Nemes,&nbsp;José Luis Martínez and José Antonio Alonso*,&nbsp;","doi":"10.1021/acsmaterialsau.3c00107","DOIUrl":"10.1021/acsmaterialsau.3c00107","url":null,"abstract":"<p >Among thermoelectric materials, skutterudites are the most prominent candidates in the mid-temperature range applications. In the multiple-filled Sr_0.2Yb_0.2Co₄Sb₁₂ skutterudite, with Sr and Yb as fillers, we have enhanced the thermoelectric performance of CoSb₃ through the reduction of lattice thermal conductivity and the optimization of carrier concentration and electrical conductivity. The high-pressure synthesis of the double-filled derivative promotes filling fraction fluctuation. This is observed by high angular resolution synchrotron X-ray diffraction, showing a phase segregation that corresponds to an inhomogeneous distribution of the filler atoms, located at the 2<i>a</i> positions of the cubic space group Im3̅. In addition, scanning transmission electron microscopy (STEM) combined with EELS spectroscopy clearly shows a segregation of Sr atoms from the surface of the grains, which is compatible with the synchrotron X-ray powder diffraction results. Mean square displacement parameters analysis results in Einstein temperatures of ∼94 and ∼67 K for Sr and Yb, respectively, and a Debye temperature of ∼250 K. The strong effect on resonant and disorder scattering yields a significantly lower lattice thermal conductivity of 2.5 W m^–1 K^–1 at 773 K. Still, good weighed-mobility values were obtained, with high filling fraction of the Yb and Sr elements. This drives a reduced electrical resistivity of 2.1 × 10^–5 Ω m, which leads to a peak <i>zT</i> of 0.26 at 773 K. The analysis and results performed for the synthesized (Sr,Yb)-double filled CoSb₃, shed light on skutterudites for potential waste-heat recovery applications.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 3","pages":"324–334"},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.3c00107","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139904180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ACS Materials Au: Announcing the 2023 Rising Stars in Materials Science","authors":"Stephanie L. Brock*,&nbsp;Maksym V. Kovalenko and Mary Ann Meador,&nbsp;","doi":"10.1021/acsmaterialsau.4c00004","DOIUrl":"10.1021/acsmaterialsau.4c00004","url":null,"abstract":"","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 2","pages":"99–106"},"PeriodicalIF":0.0,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.4c00004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139760698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Salt Effects on the Mechanical Properties of Ionic Conductive Polymer: A Molecular Dynamics Study","authors":"Harish Gudla,&nbsp;Kristina Edström and Chao Zhang*,&nbsp;","doi":"10.1021/acsmaterialsau.3c00098","DOIUrl":"10.1021/acsmaterialsau.3c00098","url":null,"abstract":"<p >Functional polymers can be used as electrolyte and binder materials in solid-state batteries. This often requires performance targets in terms of both the transport and mechanical properties. In this work, a model ionic conductive polymer system, i.e., poly(ethylene oxide)-LiTFSI, was used to study the impact of salt concentrations on mechanical properties, including different types of elastic moduli and the viscoelasticity with both nonequilibrium and equilibrium molecular dynamics simulations. We found an encouragingly good agreement between experiments and simulations regarding Young’s modulus, bulk modulus, and viscosity. In addition, we identified an intermediate salt concentration at which the system shows high ionic conductivity, high Young’s modulus, and short elastic restoration time. Therefore, this study laid the groundwork for investigating ionic conductive polymer binders with self-healing functionality from molecular dynamics simulations.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 3","pages":"300–307"},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.3c00098","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139680016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resistive Avalanches in La1–xSrxCoO3−δ (x = 0, 0.3) Thin Films and Their Reversible Evolution by Tuning Lattice Oxygen Vacancies (δ)","authors":"Soumya Biswas,&nbsp;Noora Naushad,&nbsp;Kalyani S and Vinayak B. Kamble*,&nbsp;","doi":"10.1021/acsmaterialsau.3c00101","DOIUrl":"10.1021/acsmaterialsau.3c00101","url":null,"abstract":"<p >Strong correlations are often manifested by exotic electronic phases and phase transitions. LaCoO_3−δ (LCO) is a system that exhibits such strong electronic correlations with lattice–spin–charge–orbital degrees of freedom. Here, we show that mesoscopic oxygen-deficient LCO films show resistive avalanches of about 2 orders of magnitude due to the metal–insulator transition (MIT) of the film at about 372 K for the 25 W RF power-deposited LCO film on the Si/SiO₂ substrate. In bulk, this transition is otherwise gradual and occurs over a very large temperature range. In thin films of LCO, the oxygen deficiency (0 &lt; δ &lt; 0.5) is more easily reversibly tuned, resulting in avalanches. The avalanches disappear after vacuum annealing, and the films behave like normal insulators (δ ∼0.5) with Co²⁺ in charge ordering alternatively with Co³⁺. This oxidation state change induces spin state crossovers that result in a spin blockade in the insulating phase, while the conductivity arises from hole hopping among the allowed cobalt Co⁴⁺ ion spin states at high temperature. The chemical pressure (strain) of 30% Sr²⁺ doping at the La³⁺ site results in reduction in the avalanche magnitude as well as their retention in subsequent heating cycles. The charge nonstoichiometry arising due to Sr²⁺ doping is found to contribute toward hole doping (i.e., Co³⁺ oxidation to Co⁴⁺) and thereby the retention of the hole percolation pathway. This is also manifested in energies of crossover from the 3D variable range hopping (VRH) type transport observed in the temperature range of 300–425 K, while small polaron hopping (SPH) is observed in the temperature range of 600–725 K for LCO. On the other hand, Sr-doped LCO does not show any crossover and only the VRH type of transport. The strain due to Sr²⁺ doping refrains the lattice from complete conversion of δ going to 0.5, retaining the avalanches.</p>","PeriodicalId":29798,"journal":{"name":"ACS Materials Au","volume":"4 3","pages":"308–323"},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmaterialsau.3c00101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139678421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}