Carbon Letters最新文献

Facile co-pyrolysis synthesis of nano si-anisotropic C composite anodes with controlled silicon dispersion for high-performance lithium-ion batteries 高性能锂离子电池用可控硅分散纳米硅-各向异性C复合阳极的易热解合成

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-07-04 DOI: 10.1007/s42823-026-01107-5

Chaehun Lim, Sangyeop Lee, Minah Kang, Seongjae Myeong, Young-Seak Lee

引用次数: 0

Li-IL@CuBTC-enhanced PEO composite polymer electrolytes for solid-state lithium batteries Li-IL@CuBTC-enhanced固态锂电池用PEO复合聚合物电解质

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-07-04 DOI: 10.1007/s42823-026-01109-3

Sung Hoon Kim, Neema Cyril Karima, Kelvin Jenerali Nyamtara, Minkyeong Kim, Younghyun Cho, Young-Woo Lee, Jaehan Lee, Yun-Seok Jun, Wook Ahn

{"title":"Li-IL@CuBTC-enhanced PEO composite polymer electrolytes for solid-state lithium batteries","authors":"Sung Hoon Kim, Neema Cyril Karima, Kelvin Jenerali Nyamtara, Minkyeong Kim, Younghyun Cho, Young-Woo Lee, Jaehan Lee, Yun-Seok Jun, Wook Ahn","doi":"10.1007/s42823-026-01109-3","DOIUrl":"10.1007/s42823-026-01109-3","url":null,"abstract":"<div><p>Polymer electrolytes in lithium batteries typically suffer from low ionic conductivity and unstable interactions with lithium metal, limiting their applicability in high-energy-density systems. To address these challenges, a novel nanoporous filler (Li-IL@CuBTC) was synthesized by encapsulating a lithium-containing ion-conductive liquid within the CuBTC metal–organic framework (MOF), and this filler was incorporated into a polyethylene oxide (PEO) matrix to form a composite polymer electrolyte. The multifunctional filler enhances ion transport, suppresses PEO crystallinity, and improves electrolyte stability. Consequently, the composite polymer electrolyte has a broad electrochemical stability window (5.9 V), strong ionic conductivity (1.2 × 10⁻<sup>4</sup> S cm⁻¹ at room temperature), and a high lithium-ion transference number (0.69), along with excellent compatibility with lithium metal. In LFP/PLLC/Li full cells operated at 60 °C, the electrolyte delivers outstanding cycling stability, maintaining reversible capacities of 160.5 mAh g⁻¹ after 200 cycles at 0.2 C and 151.5 mAh g⁻¹ after 250 cycles at 0.2 C and 2 C respectively. This study demonstrates an effective strategy for improving composite polymer electrolytes, offering promising potential for safe, durable, and high-energy-density energy storage systems.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1983 - 1997"},"PeriodicalIF":6.2,"publicationDate":"2026-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Charcoal to graphene: a sustainable route via electrochemical exfoliation 木炭到石墨烯：通过电化学剥离的可持续路线

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-29 DOI: 10.1007/s42823-026-01108-4

Thiraset Suksaenkraisorn, Chanokphat Thana-dachophol, Kanokon Somkaew, Porpin Pungetmongkol

{"title":"Charcoal to graphene: a sustainable route via electrochemical exfoliation","authors":"Thiraset Suksaenkraisorn, Chanokphat Thana-dachophol, Kanokon Somkaew, Porpin Pungetmongkol","doi":"10.1007/s42823-026-01108-4","DOIUrl":"10.1007/s42823-026-01108-4","url":null,"abstract":"<div><p>Producing high-quality pristine graphene remains a major bottleneck for its widespread technological adoption due to the cost and limitations of conventional synthesis methods. Here, we emphasize biomass-derived charcoal as a sustainable, low-cost, and readily available carbon precursor, offering a practical alternative to traditional graphite sources. We demonstrate a simple and economical approach for graphene production involving charcoal pretreatment, controlled electrochemical exfoliation, surfactant-assisted sonication, and filtration. Comprehensive characterization using HRTEM, FESEM, EDS, XRD, XPS, AFM, FTIR and Raman spectroscopy confirms the formation of few-layer and single-layer graphene with structural properties comparable to commercial-grade materials. Electrochemical evaluation on graphene-modified screen-printed electrodes shows a 105% increase in electron mobility and a 17% reduction in charge transfer resistance, indicating enhanced electrical performance. These results highlight the potential of charcoal as a renewable carbon feedstock and establish a cost-effective, environmentally friendly pathway for graphene production, enabling applications in energy storage, sensing, and next-generation electronic devices.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1969 - 1981"},"PeriodicalIF":6.2,"publicationDate":"2026-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Activated carbon in microbial fuel cell: a role based-perspective 活性炭在微生物燃料电池中的作用研究

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-29 DOI: 10.1007/s42823-026-01098-3

M. S. Gayathri, Devu Bindhu, Anju Ramachandran, I. Jinchu, B. Neethu, F.I. Ezema, C. O. Sreekala

{"title":"Activated carbon in microbial fuel cell: a role based-perspective","authors":"M. S. Gayathri, Devu Bindhu, Anju Ramachandran, I. Jinchu, B. Neethu,  F.I. Ezema, C. O. Sreekala","doi":"10.1007/s42823-026-01098-3","DOIUrl":"10.1007/s42823-026-01098-3","url":null,"abstract":"<div><p>Activated carbon (AC) has become a key material in microbial fuel cell technology (MFC), thanks to its high surface area, tunable porosity, structure-dependent electrical conductivity and sustainable origin. This review intends to present a role-based perspective on the functions of AC in the major MFC components including the anode, cathode and proton exchange membrane (PEM). The effects of the precursor, activation method and processing parameters on the physicochemical and electrochemical properties of AC are critically analysed. In anodes, AC enhances microbial adhesion and extracellular electron transfer through oxygenated surface groups and hierarchical porosity. As a cathode catalyst, metal- and nitrogen-doped AC promotes efficient oxygen reduction reactions comparable to Pt-based systems, while drastically lowering costs. In PEMs, AC-based composites improve proton transport, water retention and mechanical integrity, offering low-cost, renewable alternatives to Nafion. The review also highlights how factors such as surface functionality, conductivity and pore structure govern electrochemical performance. Finally, emerging strategies like biomass activation, heteroatom doping, nanohybrid design and AI-driven optimization are identified as pathways toward scalable, high-performance and circular-economy-based MFC systems.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1475 - 1502"},"PeriodicalIF":6.2,"publicationDate":"2026-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cavity miniaturization and cluster interconnectivity enable high-capacity and fast-charging hollow carbon for lithium-ion battery anodes 空腔的小型化和簇的互联性使锂离子电池阳极的中空碳具有高容量和快速充电的能力

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-22 DOI: 10.1007/s42823-026-01105-7

Fan Wang, Yuan Zhou, Zhongli Hu, Weihua Wang, Liyuan Sha, Xinran Huang, Tao Hu, Li Zhang

{"title":"Cavity miniaturization and cluster interconnectivity enable high-capacity and fast-charging hollow carbon for lithium-ion battery anodes","authors":"Fan Wang, Yuan Zhou, Zhongli Hu, Weihua Wang, Liyuan Sha, Xinran Huang, Tao Hu, Li Zhang","doi":"10.1007/s42823-026-01105-7","DOIUrl":"10.1007/s42823-026-01105-7","url":null,"abstract":"<div><p>Hollow carbon spheres (HCSs) have emerged as promising anode materials for lithium-ion batteries (LIBs), yet their practical application is hindered by intrinsic limitations. Excessive internal voids reduce the tapped density and volumetric energy density, while poor interparticle connectivity increases transport resistance and compromises rate capability. Here, we present a series of nitrogen-doped hollow carbon sphere clusters (HCSCs) with varying hollow diameters (20 nm, 100 nm, and 300 nm), achieved via a combined spray-drying and solution-stirring approach. The 20-HCSCs with ultra-small cavities (20 nm) markedly enhances tap density, while cluster-level interconnectivity establishes continuous pathways for efficient Li<sup>+</sup> and electron transport, thereby enabling rapid charge/discharge kinetics and high volumetric capacity. Consequently, the 20-HCSCs electrodes exhibit an exceptional reversible capacity of 447.3 mAh cm<sup>-3</sup> after 90 cycles at 0.2 C, surpassing that of 100-HCSCs, 300-HCSCs electrodes and conventional graphite electrodes (around 372 mAh cm<sup>-3</sup>), and demonstrate remarkable high-rate cyclability, retaining 68.5 mAh cm<sup>-3</sup> after 3000 cycles at 50 C. The ultrahigh volumetric capacity mitigates the volumetric penalty typically imposed by hollow structures, offering a viable strategy to reconcile high capacity, fast-charging capability, and competitive volumetric performance in carbonaceous anodes.</p><h3>Graphical abstract</h3><p>Ultra-small-cavity HCSC anodes with both high volumetric energy density and fast-charging capability </p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1955 - 1967"},"PeriodicalIF":6.2,"publicationDate":"2026-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Crystallinity-controlled, kenaf fiber-derived activated carbons with high mesopore ratio for high-rate supercapacitors with aqueous and organic electrolytes 具有高介孔比的红麻纤维衍生的结晶控制活性炭，用于含水和有机电解质的高速超级电容器

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-22 DOI: 10.1007/s42823-026-01091-w

Keon-ho Kong, Juntae Kim, Kye-yeol Lee, Il Yeong Jeong, Sivaprakasam Radhakrishnan, Danyun Lei, Hye‑Min Lee, Byoung-Suhk Kim

{"title":"Crystallinity-controlled, kenaf fiber-derived activated carbons with high mesopore ratio for high-rate supercapacitors with aqueous and organic electrolytes","authors":"Keon-ho Kong, Juntae Kim, Kye-yeol Lee, Il Yeong Jeong, Sivaprakasam Radhakrishnan, Danyun Lei, Hye‑Min Lee, Byoung-Suhk Kim","doi":"10.1007/s42823-026-01091-w","DOIUrl":"10.1007/s42823-026-01091-w","url":null,"abstract":"<div><p>This study reports the development of high-performance supercapacitor electrodes derived from biomass kenaf fibers (KFs) through hydrothermal pretreatment and steam activation. The hydrothermal treatment significantly enhances the crystallinity of cellulose, resulting in improved thermal and structural stability. This enhanced crystallinity effectively mitigates common issues, such as pore collapse and structural degradation during prolonged steam activation. Notably, hydrothermally treated KFs (HKFs) maintain structural integrity even after 3 h of steam activation at 900 °C. The resulting activated carbon (HKF-200-3) exhibits a high surface area of 1675.1 m² g<sup>− 1</sup> and a mesopore ratio of 47.2%. The HKF-200-3 based coin cell delivers a specific capacitance of 28.9 F g<sup>− 1</sup> (at 1 A g<sup>− 1</sup>) in 6 M aqueous KOH electrolyte and 25.2 F g<sup>− 1</sup> (at 1 A g<sup>− 1</sup>) 1 M DMPBF4/AN organic electrolyte, demonstrating excellent rate capability. The device achieves an energy density of 25.99 Wh kg<sup>− 1</sup> and a power density of 675 W kg<sup>− 1</sup>, along with 82% capacitance retention after 100,000 cycles. This work presents a promising strategy for the preparation of crystallinity-controlled biomass-derived activated carbons for sustainable energy storage applications.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1809 - 1823"},"PeriodicalIF":6.2,"publicationDate":"2026-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148459001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Recent progress of covalent organic frameworks as catalysts for green and renewable fuel production 共价有机框架在绿色和可再生燃料生产中的催化剂研究进展

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-20 DOI: 10.1007/s42823-026-01099-2

Febio Dalanta, Susilo Sudarman, Muhammadin Hamid, Rahmadina Rahmadina, Ardiansyah Sembiring, Muhammad Iqbal Hidayat

{"title":"Recent progress of covalent organic frameworks as catalysts for green and renewable fuel production","authors":"Febio Dalanta, Susilo Sudarman, Muhammadin Hamid, Rahmadina Rahmadina, Ardiansyah Sembiring, Muhammad Iqbal Hidayat","doi":"10.1007/s42823-026-01099-2","DOIUrl":"10.1007/s42823-026-01099-2","url":null,"abstract":"<div><p>Covalent Organic Frameworks (COFs) have emerged as a preeminent class of crystalline porous materials, bridging the gap between molecular precision and heterogeneous photo-electrocatalysis. This review highlights recent breakthroughs in COF-based materials, emphasizing how their unique architectural features including long-range π-conjugation, permanent porosity, and modular tunability to enable superior photon harvesting and accelerated charge carrier dynamics for renewable fuel generations. Specifically, the synthesis methods, fundamental principles, linkage and block bond effects, and applicable design strategies of COFs are reviewed. We also summarize and criticize current literature related to the fundamental mechanisms driving key transformations of COFs in the targeted application such as hydrogen evolution, CO<sub>2</sub> reduction, nitrogen fixation, and H<sub>2</sub>O<sub>2</sub> production, as the core study of this review. The strategic refinements in synthesis, architectural properties, and co-catalyst integration that have pushed performance of COFs toward industrial relevance are also discussed. Further challenges and potentials of COFs in energy generation sector are critically suggested. Ultimately, this review provides a critical perspective on the evolving role of COFs in green fuel production, serving as a strategic roadmap for the development of next-generation materials essential to achieving global net-zero emissions and sustainable future.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1503 - 1537"},"PeriodicalIF":6.2,"publicationDate":"2026-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Directly integrated hierarchical 3D porous graphene/silicon Schottky photodetectors for self-powered operation 直接集成分层三维多孔石墨烯/硅肖特基光电探测器，用于自供电操作

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-19 DOI: 10.1007/s42823-026-01095-6

Hong Gun Kim, Hee Ra Lee, Junyeong Kim, Tae-Wook Kim, Sukang Bae, Spyros N. Yannopoulos, Jong-Seong Bae, Seoung-Ki Lee

{"title":"Directly integrated hierarchical 3D porous graphene/silicon Schottky photodetectors for self-powered operation","authors":"Hong Gun Kim, Hee Ra Lee, Junyeong Kim, Tae-Wook Kim, Sukang Bae, Spyros N. Yannopoulos, Jong-Seong Bae, Seoung-Ki Lee","doi":"10.1007/s42823-026-01095-6","DOIUrl":"10.1007/s42823-026-01095-6","url":null,"abstract":"<div><p>Graphene/Si Schottky photodetectors have exhibited significant broadband photoresponse; however, the inherently low optical absorption of graphene remains a major obstacle to the development of high-performance, scalable devices. In this work, a self-powered broadband photodetector based on a three-dimensional porous graphene (3DPG)/Si Schottky junction was demonstrated, in which the 3DPG was directly integrated onto a silicon substrate via laser-induced layer-selective graphitization. This approach enables the transfer-free formation of a hierarchical porous graphene network while simultaneously establishing a structurally and electronically integrated heterointerface, thus overcoming the limitations associated with planar graphene structures. The porous graphene architecture enhances light absorption and effective surface area, while residual oxygen-containing functional groups induce p-type doping, which increases the Schottky barrier height and strengthens the built-in electric field. As a result, the device exhibited a photocurrent approximately 20 times higher than those of planar CVD-Gr/Si devices, along with a high on/off ratio of 1.91 × 10<sup>5</sup>, a maximum responsivity of 1.32 A/W, and a specific detectivity of 1.57 × 10<sup>13</sup> Jones at 940 nm under zero-bias conditions. These results demonstrate that the direct integration of 3DPG, combined with its simple and scalable fabrication process, provides a promising platform for high-performance, broadband, self-powered Si-based photodetectors.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1839 - 1851"},"PeriodicalIF":6.2,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Morphological and electrochemical properties of ZIF-8/biomass-activated carbon hybrids for the anode of lithium-ion battery 锂离子电池负极ZIF-8/生物质活性炭杂化材料的形态和电化学性能

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-18 DOI: 10.1007/s42823-026-01102-w

Muhammad Bima Yudha SY, Metta Noviani Rahmat Halim, Abdulloh Rifai, Fajar Inggit Pambudi

{"title":"Morphological and electrochemical properties of ZIF-8/biomass-activated carbon hybrids for the anode of lithium-ion battery","authors":"Muhammad Bima Yudha SY, Metta Noviani Rahmat Halim, Abdulloh Rifai, Fajar Inggit Pambudi","doi":"10.1007/s42823-026-01102-w","DOIUrl":"10.1007/s42823-026-01102-w","url":null,"abstract":"<div><p>This study reports the successful synthesis of a hybrid anode material by integrating zeolitic imidazolate framework-8 (ZIF-8) with biomass-derived activated carbon (AC) from coconut tree waste (ZIF-8-AC) and its calcined derivative (ZIF-8-AC-800). Structural and morphological analyses via XRD, SEM, and TEM confirm the preservation of ZIF-8 dodecahedral crystallinity and its uniform dispersion on the AC matrix. Post-calcination at 800 °C retains ZIF-8 framework-derived ZnO phase while enhancing graphitic ordering in the AC, as evidenced by FTIR and Raman spectroscopy. Electrochemical characterization reveals that ZIF-8-AC-800 exhibits a low charge transfer resistance (41.9 Ω) compared to ZIF-8-AC (53.3 Ω), attributed to improved electrical conductivity from carbonization. As a Lithium-ion battery (LIB) anode, ZIF-8-AC-800 delivers a high reversible specific capacity of 491 mAh g⁻¹ at 0.1 C, outperforming non-calcined ZIF-8-AC (223 mAh g⁻¹) due to synergistic effects between the conductive AC matrix and ZnO lithiation activity. The hybrid hierarchical porosity, facilitated by ZIF-8 microporosity and AC macropores, enhances Li<sup>+</sup> diffusion kinetics and structural stability during cycling. This work underscores the potential of MOF-biomass carbon hybrids as eco-friendly anode materials and provides a simple laboratory-scale synthesis strategy that may be further optimized for future scale-up.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1927 - 1942"},"PeriodicalIF":6.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of rGO/NiO nanocomposite recovered from spent Ni-MH batteries for energy storage device applications 从废镍氢电池中回收的还原氧化石墨烯/NiO纳米复合材料在储能器件中的应用

IF 6.2 3区材料科学

Carbon Letters Pub Date : 2026-06-15 DOI: 10.1007/s42823-026-01100-y

M. Mylarappa, S. Chandruvasan, V. Venkatalakshmi, G. Krishnamurthy

{"title":"Development of rGO/NiO nanocomposite recovered from spent Ni-MH batteries for energy storage device applications","authors":"M. Mylarappa, S. Chandruvasan, V. Venkatalakshmi, G. Krishnamurthy","doi":"10.1007/s42823-026-01100-y","DOIUrl":"10.1007/s42823-026-01100-y","url":null,"abstract":"<div><p>The recycling of end-of-life nickel–metal hydride (Ni–MH) batteries offers an attractive pathway to recover valuable metals and convert them into functional materials for energy storage. In this work, nickel hydroxide was recovered from spent Ni–MH batteries through an acid-leaching and alkaline precipitation process, followed by thermal conversion to NiO. The recovered NiO was integrated with reduced graphene oxide (rGO) via a reflux-assisted method to obtain an rGO/NiO nanocomposite electrode. Structural and morphological analyses confirmed the formation of crystalline NiO uniformly anchored to conductive rGO sheets, yielding a high specific surface area of 289.6 m<sup>2</sup>g<sup>-1</sup>. Electrochemical measurements performed in a three-electrode configuration revealed pronounced pseudocapacitive behavior associated with reversible Ni<sup>2+</sup>/Ni<sup>3+</sup> redox reactions. The rGO/NiO electrode delivered a high specific capacitance of 2256.1 Fg<sup>-1</sup> at 1 Ag<sup>-1</sup> with a low charge-transfer resistance of 3.77 Ω. The device, an asymmetric supercapacitor (ASC), was fabricated with rGO/NiO as the positive electrode and activated carbon as the negative electrode. The assembled rGO/NiO//AC device achieved a specific capacitance of 657 Fg<sup>-1</sup> and an energy density of 44.7 Whkg<sup>-1</sup> at a power density of 348 Wkg<sup>-1</sup>, calculated based on the total mass of active materials in both electrodes. The device also exhibited excellent cycling stability, with 97.6% capacitance retention after 10,000 cycles. These results demonstrate that nickel recovered from spent batteries can serve as a promising precursor for high-performance supercapacitor electrodes.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1883 - 1910"},"PeriodicalIF":6.2,"publicationDate":"2026-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148459048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0