Advanced Powder Materials最新文献

{"title":"Promoting effect of interfacial hole accumulation on photoelectrochemical water oxidation in BiVO4 and Mo-doped BiVO4","authors":"Xiaofeng Wu ,&nbsp;Freddy E. Oropeza ,&nbsp;Shixin Chang ,&nbsp;Marcus Einert ,&nbsp;Qingyang Wu ,&nbsp;Clément Maheu ,&nbsp;Julia Gallenberger ,&nbsp;Chuanmu Tian ,&nbsp;Kangle Lv ,&nbsp;Jan P. Hofmann","doi":"10.1016/j.apmate.2024.100234","DOIUrl":"10.1016/j.apmate.2024.100234","url":null,"abstract":"<div><div>Hole transfer at the semiconductor-electrolyte interface is a key elementary process in (photo)electrochemical (PEC) water oxidation. However, up to now, a detailed understanding of the hole transfer and the influence of surface hole density on PEC water oxidation kinetics is lacking. In this work, we propose a model for the first time in which the surface accumulated hole density in BiVO₄ and Mo-doped BiVO₄ samples during water oxidation can be acquired via employing illumination-dependent Mott-Schottky measurements. Based on this model, some results are demonstrated as below: (1) Although the surface hole density increases when increasing light intensity and applied potential, the hole transfer rate remains linearly proportional to surface hole density on a log-log scale. (2) Both water oxidation on BiVO₄ and Mo-doped BiVO₄ follow first-order reaction kinetics at low surface hole densities, which is in good agreement with literature. (3) We find that water oxidation active sites in both BiVO₄ and Mo-doped BiVO₄ are very likely to be Bi⁵⁺, which are produced by photoexcited or/and electro-induced surface holes, rather than VO_<em>x</em> species or Mo⁶⁺ due to their insufficient redox potential for water oxidation. (4) Introduction of Mo doping brings about higher OER activity of BiVO₄, as it suppresses the recombination rate of surface holes and increases formation of Bi⁵⁺. This surface hole model offers a general approach for the quantification of surface hole density in the field of semiconductor photoelectrocatalysis.</div></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 6","pages":"Article 100234"},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434169","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":"Emerging semiconductor ionic materials tailored by mixed ionic-electronic conductors for advanced fuel cells","authors":"Bushra Bibi ,&nbsp;Atif Nazar ,&nbsp;Bin Zhu ,&nbsp;Fan Yang ,&nbsp;Muhammad Yousaf ,&nbsp;Rizwan Raza ,&nbsp;M.A.K. Yousaf Shah ,&nbsp;Jung-Sik Kim ,&nbsp;Muhammad Afzal ,&nbsp;Yongpeng Lei ,&nbsp;Yifu Jing ,&nbsp;Peter Lund ,&nbsp;Sining Yun","doi":"10.1016/j.apmate.2024.100231","DOIUrl":"10.1016/j.apmate.2024.100231","url":null,"abstract":"<div><div>Mixed ionic-electronic conductors (MIECs) play a crucial role in the landscape of energy conversion and storage technologies, with a pronounced focus on electrode materials’ application in solid oxide fuel cells (SOFCs) and proton-conducting ceramic fuel cells (PCFCs). In parallel, the emergence of semiconductor ionic materials (SIMs) has introduced a new paradigm in the field of functional materials, particularly for both electrode and electrolyte development for low-temperature, 300–550 ​°C, SOFCs, and PCFCs. This review article critically delves into the intricate mechanisms underpinning the synergistic relationship between MIECs and SIMs, with a particular emphasis on elucidating the fundamental working principles of semiconductor ionic membrane fuel cells (SIMFCs). By exploring critical facets such as ion-coupled electron transfer/transport, junction effect, energy bands alignment, and theoretical computations, it casts an illuminating spotlight on the transformative potential of MIECs, also involving triple charge conducting oxides (TCOs) in the context of SIMs and advanced fuel cells (FCs). The insights and findings articulated herein contribute substantially to the advancement of SIMs and SIMFCs by tailoring MIECs (TCOs) as promising avenues toward the emergence of high-performance SIMFCs. This scientific quest not only addresses the insistent challenges surrounding efficient charge transfer, ionic transport and power output but also unlocks the profound potential for the widespread commercialization of FC technology<strong>.</strong></div></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 6","pages":"Article 100231"},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358238","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":"Advances in powder nano-photocatalysts as pollutant removal and as emerging contaminants in water: Analysis of pros and cons on health and environment","authors":"Sahil Thakur ,&nbsp;Abhijeet Ojha ,&nbsp;Sushil Kumar Kansal ,&nbsp;Navneet Kumar Gupta ,&nbsp;Hendrik C. Swart ,&nbsp;Junghyun Cho ,&nbsp;Andrej Kuznetsov ,&nbsp;Shuhui Sun ,&nbsp;Jai Prakash","doi":"10.1016/j.apmate.2024.100233","DOIUrl":"10.1016/j.apmate.2024.100233","url":null,"abstract":"<div><div>Photocatalysis is an advanced oxidation process where light exposure triggers a semiconducting nanomaterial (nano-photocatalyst) to generate electron-hole (e⁻/h⁺) pairs and free radicals. This phenomenon is widely used for the photocatalysis-assisted removal of organic and other contaminants using wide range of nano-photocatalysts, offering an efficient approach to environmental remediation. However, the introduction of powdered nano-photocatalysts into water systems often leads to unintended secondary pollution in the form of residual nano-photocatalysts, ion leaching, free radicals, toxic by-products etc. Such practices potentially introduce emerging secondary contaminants into aquatic environments, posing risks to both aquatic life and human health. The resulting chemical by-products and intermediates can effectively induce chronic toxicity, neurological and developmental disorders, cardiovascular defects, and intestinal ailments in humans and aquatic species. Despite having a range of health and environmental consequences, this dark side of nano-photocatalysts has been comparatively less explored and discussed in the literature. In this review, the pros and cons of powder nano-photocatalysts are discussed in view of their advantages as well as disadvantages in wastewater treatment. The discussion encompasses their classification based on composition, dimensions, structure, and activity, as well as recent advancements in improving their photocatalytic efficiency. The article also explores the recent advances on their applications in photocatalytic removal of various water pollutants/contaminants of emerging concern (i.e., organic pollutants, micro/nano plastics, heavy ions, disinfections, etc.) Furthermore, an emphasis on the role of such nano-photocatalysts as emerging (secondary) contaminants in water system, along with a thorough discussion of latest studies related to the health and environmental issues, has been discussed. Additionally, it addresses critical issues in applying powder nano-photocatalysts for wastewater detoxification and explores potential solutions to these challenges followed by future prospects.</div></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 6","pages":"Article 100233"},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441374","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":"Surface engineering of nickel-rich single-crystal layered oxide cathode enables high-capacity and long cycle-life sulfide all-solid-state batteries","authors":"Xuebao Li ,&nbsp;Jiasen Wang ,&nbsp;Cheng Han ,&nbsp;Kun Zeng ,&nbsp;Zhuangzhi Wu ,&nbsp;Dezhi Wang","doi":"10.1016/j.apmate.2024.100228","DOIUrl":"10.1016/j.apmate.2024.100228","url":null,"abstract":"<div><p>Sulfide all-solid-state lithium batteries (SASSLBs) with a single-crystal nickel-rich layered oxide cathode (LiNi_<em>x</em>Co_<em>y</em>Mn_{1-<em>x</em>-<em>y</em>}O₂, <em>x</em> ​≥ ​0.8) are highly desirable for advanced power batteries owing to their excellent energy density and safety. Nevertheless, the cathode material's cracking issue and its severe interfacial problem with sulfide solid electrolytes have hindered the further development. This study proposes to employ surface modification engineering to produce B-NCM cathode materials coated with boride nanostructure stabilizer in situ by utilizing NCM encapsulated with residual lithium. This approach enhances the electrochemical performance of SASSLBs by effectively inhibiting electrochemical-mechanical degradation of the NCM cathode material on cycling and reducing deleterious side reactions with the solid sulfide electrolyte. The B-NCM/LPSCl/Gr SASSLBs demonstrate impressive cycling stability, retaining 84.19 ​% of its capacity after 500 cycles at 0.2 ​C, which represents a 30.13 ​% increase vs. NCM/LPSCl/Gr. It also exhibits a specific capacity of 170.4 mAh/g during its first discharge at 0.1 ​C. This work demonstrates an effective surface engineering strategy for enhancing capacity and cycle life, providing valuable insights into solving interfacial problems in SASSLBs.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100228"},"PeriodicalIF":0.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000599/pdfft?md5=d3b60979e51850a599f1440f00d030e5&pid=1-s2.0-S2772834X24000599-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142048835","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":"New lead-free chemistry for in-situ monitoring of advanced nuclear power plant","authors":"Lexing Liang ,&nbsp;Xiuling Wang ,&nbsp;Cong Zhang ,&nbsp;Kailei Lu ,&nbsp;Guangfan Tan ,&nbsp;Yanhao Dong ,&nbsp;Yanli Shi ,&nbsp;Jianqi Qi ,&nbsp;Tiecheng Lu","doi":"10.1016/j.apmate.2024.100229","DOIUrl":"10.1016/j.apmate.2024.100229","url":null,"abstract":"<div><p>Nuclear power is essential for sustainable energy infrastructure and economic development, necessitating materials for high-radiation environments that can facilitate visualization and observation. Conventional lead glass is inadequate for future requirements due to radiation-induced darkening, poor mechanical properties, and toxicity. Therefore, there is urgent to find new window materials that offer multi-ionization shielding (particularly against deep-penetrating gamma ray, γ, and neutron, n, radiations), desirable opto-mechanical properties, service stability against darkening, and non-toxicity. In this study, we report a family of transparent rare-earth pyrochlore ceramics La_<em>x</em>Gd_{2−<em>x</em>}Zr₂O₇, offering unique chemo-physical properties that are ideal for robust radiation shielding windows. Remarkably, we demonstrated the capability of maintaining high transparency under heavy-dose exposure to 1000 ​kGy ⁶⁰Co γ radiation. We observed the service stability against radiation darkening can be greatly enhanced with La-rich compositions, while Gd-rich compositions undergo shallow darkening that can be reversibly recovered under visible light. This behavior is attributed to mitigated oxygen migration from 48f to 8a in La-rich compositions, which have high pyrochlore phase stability and well-ordered atomic structures, and reversible oxygen migration between 48f and 8a in Gd-rich compositions, which remain active at room temperature. Our proposal and demonstration unlock ample opportunities in designing functional transparent ceramics as window materials for demanding applications in high-radiation environments.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100229"},"PeriodicalIF":0.0,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000605/pdfft?md5=c08c3029d74ec16a4160991e2c6aa307&pid=1-s2.0-S2772834X24000605-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142129111","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":"A comprehensive review on catalysts for seawater electrolysis","authors":"Jihong Li ,&nbsp;Genyuan Fu ,&nbsp;Xiaokun Sheng ,&nbsp;Guodong Li ,&nbsp;Hui Chen ,&nbsp;Kaiqian Shu ,&nbsp;Yan Dong ,&nbsp;Tongzhou Wang ,&nbsp;Yida Deng","doi":"10.1016/j.apmate.2024.100227","DOIUrl":"10.1016/j.apmate.2024.100227","url":null,"abstract":"<div><p>Seawater electrolysis is a sustainable energy conversion technology that generates clean energy by splitting seawater into hydrogen and oxygen. However, the catalysts used in seawater electrolysis often face significant stability challenges because of the high concentration of salt ions and other impurities present in seawater. This review aims to discern the pivotal factors influencing catalyst stability in seawater electrolysis, elucidate the corrosion and electrochemical degradation mechanisms, and delve into the various strategies employed to enhance catalyst stability. These strategies encompass catalyst material selection, surface modification techniques, catalyst support materials, and catalyst design strategies. By gaining deeper insights into the obstacles and innovations concerning catalyst stability in seawater electrolysis, this review strives to expedite progress toward the commercialization and widespread adoption of this technology as a renewable and feasible approach for hydrogen production. Ultimately, the goal is to foster a cleaner and more sustainable future by enabling the efficient and enduring generation of hydrogen from seawater.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100227"},"PeriodicalIF":0.0,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000587/pdfft?md5=c4187905caa66351543df1dc636a16b8&pid=1-s2.0-S2772834X24000587-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142087588","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":"3D printing of flexible piezoelectric composite with integrated sensing and actuation applications","authors":"Jiang Li ,&nbsp;Yan Zhang ,&nbsp;Mingyang Yan ,&nbsp;Chao Zhong ,&nbsp;Lianzhong Zhao ,&nbsp;Di Zhai ,&nbsp;Hang Luo ,&nbsp;Xi Yuan ,&nbsp;Dou Zhang","doi":"10.1016/j.apmate.2024.100226","DOIUrl":"10.1016/j.apmate.2024.100226","url":null,"abstract":"<div><p>3D printing of flexible piezoelectric composites (3D-FPCs) is increasingly attracting the attention due to its unique advantage for customized smart applications. However, current research mainly focuses on the 0–3 piezoelectric composites, in which the piezoelectric ceramics are embedded in polymer matrix in the form of particles. The poor connectivity between particles much reduces the conduction of strain and charge in the composites, seriously limiting its application in actuation. In this work, a continuous lead zirconate titanate (PZT) double-layer ceramic scaffold was prepared by 3D printing and assembled with epoxy resin and interdigital electrodes together to manufacture a multifunctional device. The 3D-FPCs exhibit a free strain of 1830 ​ppm in actuating and are able to actuate a stainless-steel cantilever beam to produce a tip displacement of 5.71 ​mm. Additionally, the devices exhibit a sensitivity of 26.81V/g in sensing applications. Furthermore, 3D-FPCs are demonstrated as actuators for mobile small robots and wearable sensors for sensing joint activities.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100226"},"PeriodicalIF":0.0,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000575/pdfft?md5=2c3249368b8ae061c9c949a14caade42&pid=1-s2.0-S2772834X24000575-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142011173","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":"Unveiling a giant electrocaloric effect at low electric fields through continuous phase transition design","authors":"Yunyao Huang ,&nbsp;Leiyang Zhang ,&nbsp;Pingji Ge ,&nbsp;Ruiyi Jing ,&nbsp;Wenjing Shi ,&nbsp;Chao Li ,&nbsp;Xiang Niu ,&nbsp;Vladimir Shur ,&nbsp;Haibo Zhang ,&nbsp;Shengguo Lu ,&nbsp;Yintang Yang ,&nbsp;Dawei Wang ,&nbsp;Xiaoqin Ke ,&nbsp;Li Jin","doi":"10.1016/j.apmate.2024.100225","DOIUrl":"10.1016/j.apmate.2024.100225","url":null,"abstract":"<div><p>The reported electrocaloric (EC) effect in ferroelectrics is poised for application in the next generation of solid-state refrigeration technology, exhibiting substantial developmental potential. This study introduces a novel and efficient EC effect strategy in (1–<em>x</em>)Pb(Lu_1/2Nb_1/2)O₃-<em>x</em>PbTiO₃ (PLN-<em>x</em>PT) ceramics for low electric-field-driven devices. Phase-field simulations provide fundamental insights into thermally induced continuous phase transitions, guiding subsequent experimental investigations. A comprehensive composition/temperature-driven phase evolution diagram is constructed, elucidating the sequential transformation from ferroelectric (FE) to antiferroelectric (AFE) and finally to paraelectric (PE) phases for <em>x</em>=0.10−0.18 components. Direct measurements of EC performance highlight <em>x</em>=0.16 as an outstanding performer, exhibiting remarkable properties, including an adiabatic temperature change (Δ<em>T</em>) of 3.03 ​K, EC strength (Δ<em>T</em>/Δ<em>E</em>) of 0.08 ​K ​cm kV⁻¹, and a temperature span (<em>T</em>_span) of 31 ​°C. The superior EC effect performance is attributed to the temperature-induced FE to AFE transition at low electric fields and diffusion phase transition behavior contributing to the wide <em>T</em>_span. This work provides valuable insights into developing high-performance EC effect across broad temperature ranges through the strategic design of continuous phase transitions, offering a simplified and economical approach for advancing ecofriendly and efficient solid-state cooling technologies.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100225"},"PeriodicalIF":0.0,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000563/pdfft?md5=be349a546d6ace2de32313c7af10175b&pid=1-s2.0-S2772834X24000563-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141845269","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":"Targeted doping induces interfacial orientation for constructing surface-functionalized Schottky junctions to coordinate redox reactions in water electrolysis","authors":"Guangping Yang ,&nbsp;Tianxiang Yang ,&nbsp;Zhiguo Wang ,&nbsp;Ke Wang ,&nbsp;Mengmeng Zhang ,&nbsp;Peter D. Lund ,&nbsp;Sining Yun","doi":"10.1016/j.apmate.2024.100224","DOIUrl":"10.1016/j.apmate.2024.100224","url":null,"abstract":"<div><p>Tuning the surface properties of catalysts is an effective method for accelerating water electrolysis. Herein, we propose a directional doping and interfacial coupling strategy to design two surface-functionalized Schottky junction catalysts for coordinating the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Directional doping with B/S atoms endows amphiphilic g-C₃N₄ with significant n-/p-type semiconductor properties. Further coupling with Fe₃C modulates the energy band levels of B–C₃N₄ and S–C₃N₄, thus resulting in functionalized Schottky junction catalysts with specific surface-adsorption properties. The space-charge region generated by the dual modulation induces a local “OH⁻- and H⁺-enriched” environment, thus selectively promoting the kinetic behavior of the OER/HER. Impressively, the designed B–C₃N₄@Fe₃C||S–C₃N₄@Fe₃C pair requires only a low voltage of 1.52 ​V to achieve efficient water electrolysis at 10 ​mA ​cm⁻². This work highlights the potential of functionalized Schottky junction catalysts for coordinating redox reactions in water electrolysis, thereby resolving the trade-off between catalytic activity and stability.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100224"},"PeriodicalIF":0.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000551/pdfft?md5=75d62da94bdae536ceaf12b9ddcf0503&pid=1-s2.0-S2772834X24000551-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141847064","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":"Nitrogen-doping assisted local chemical heterogeneity and mechanical properties in CoCrMoW alloys manufactured via laser powder bed fusion","authors":"Wenting Jiang ,&nbsp;Ruidi Li ,&nbsp;Junyang He ,&nbsp;Song Ni ,&nbsp;Li Wang ,&nbsp;Zibin Chen ,&nbsp;Yi Huang ,&nbsp;Caiju Li ,&nbsp;Jianhong Yi ,&nbsp;Min Song","doi":"10.1016/j.apmate.2024.100217","DOIUrl":"10.1016/j.apmate.2024.100217","url":null,"abstract":"<div><p>CoCrMoW alloys with different nitrogen (N) additions (0, 0.05, 0.1, and 0.2 ​wt%) were prepared via laser powder bed fusion (LPBF). The effects of N content on the microstructure and mechanical properties were investigated. The results indicate that the LPBFed CoCrMoW alloy with 0.1 ​wt% N addition (0.1 ​N alloy) shows the best combination of mechanical properties with a yield strength of ∼983 ​MPa and an elongation of ∼19 ​%. Both the LPBF process and the N addition impose great effects on suppressing the γ to ε martensitic transformation, resulting in a decrease in the width and amount of ε laths/stacking faults. Besides, the N addition promotes the segregation of elements Mo, W, and Si along the cellular sub-grain boundaries (CBs), forming fine and discontinuous precipitates rich in Mo, W and Si along the CBs in the 0.1 ​N alloy, but dense and continuous (Mo,W)₅Si₃ precipitates along the CBs in the 0.2 ​N alloy. The (Mo,W)₅Si₃ precipitates with a tetragonal structure were observed and characterized for the first time in the Co–Cr based alloys. The negative mixing enthalpy between the non-metallic elements N, Si and the metallic elements Mo, W, Cr, and the rapid solidification induced segregation of high melting point elements such as Mo and W along CBs during LPBF process, synergistically contribute to the chemical heterogeneity in the alloys. The pure FCC matrix, the slightly increased segregation of Mo, W, Si elements and fine precipitates along the CBs contribute to the good combination of strength and elongation of the 0.1 ​N alloy. However, though pure FCC phase was present in the 0.2 ​N alloy, the dense and continuous (Mo,W)₅Si₃ precipitates along CBs acted as nucleation sites for cracks, deteriorating the elongation of the alloy. Overall, it is possible to tune the mechanical properties of the LPBFed CoCrMoW alloy by adjusting the local chemical heterogeneity.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":"3 5","pages":"Article 100217"},"PeriodicalIF":0.0,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X24000484/pdfft?md5=dbc6179d1fb2e5c35355045e5ad1207b&pid=1-s2.0-S2772834X24000484-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141843053","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}