Demystifying the Semiconductor-to-Metal Transition in Amorphous Vanadium Pentoxide: The Role of Substrate/Thin Film Interfaces A. Carmel Mary Esther, G. Mohan Muralikrishna, Manohar Chirumamilla, Manoel da Silva Pinto, Stefan Ostendorp, et al. Advanced Functional Materials, 2024 The precise mechanism governing the reversible semiconductor‐to‐metal transition (SMT) in V2O5 remains elusive, yet its investigation is of paramount importance due to the remarkable potential of V2O5 as a versatile “smart” material in advancing optoelectronics, plasmonics, and photonics. In this study, distinctive experimental insights into the SMT occurring in amorphous V2O5 through the application of highly sensitive, temperature‐dependent, in situ analyses on a V2O5 thin film deposited on soda‐lime glass are presented. The ellipsometry measurements reveal that the complete SMT occurs at ≈340 °C. Remarkably, the refractive index and extinction coefficients exhibit reversible characteristics across visible and near‐infrared wavelengths, underscoring the switch‐like behavior inherent to V2O5. The findings obtained from ellipsometry are substantiated by calorimetry and in situ secondary ion mass spectrometry analyses. In situ electron microscopy observations unveil a separation of oxidation states within V2O5 at 320 °C, despite the thin film retaining its amorphous state. The comprehensive experimental investigations effectively demonstrate that alterations in electronic state can trigger the SMT in amorphous V2O5. It is revealed for the first time that the SMT in V2O5 is solely contingent upon electronic state changes, independent of structural transitions, and importantly, it is a reversible transformation within the amorphous state itself.
Evolution of phase constitution with mechanical alloying and spark plasma sintering of nanocrystalline Al xCoCrFeNi (x = 0, 0.3, 0.6, 1 mol) high-entropy alloys Rahul Bhattacharya, Murugesan Annasamy, Pavel Cizek, M. Kamaraj, G. Mohan Muralikrishna, et al. Journal of Materials Research, 2022 Nanocrystalline Al_ x CoCrFeNi ( x = 0, 0.3, 0.6, 1 mol) high-entropy alloys were synthesized by mechanical alloying (MA) and consolidated by spark plasma sintering (SPS). Single-phase face-centered cubic (FCC) structure was achieved with x = 0 and 0.3. Dual-phase body-centered cubic (BCC)/B2 + FCC structure was obtained in x = 0.6 and 1. Complete solid solution was achieved with a significantly reduced duration of MA (10 h) followed by a brief SPS leading to crystallite size of < 10 nm for MA powders and < 60 nm post-SPS. Incremental changes in Al content translate into increase of BCC + B2 phase fraction and alter the co-existing FCC phase composition consequently. Ni dominates FCC phase of CoCrFeNi and Al_0.3CoCrFeNi, whereas Fe dominates FCC phase of Al_0.6CoCrFeNi and AlCoCrFeNi. Carbon and Oxygen addition during milling process resulted in nanoscale dispersion of Cr_7C_3 carbide and Cr_2O_3 /Al_2O_3 post-SPS. The hardness of AlCoCrFeNi (730HV_0.3) was the highest among all MA-SPS alloys. Graphical abstract
Retarded relaxation of grain boundaries’ non-equilibrium state in medium-entropy CoFeNi alloy probed by radiotracer diffusion B Yadav, A Burla, GM Muralikrishna, N Chandrasekaran, KG Pradeep, ... Scripta Materialia 275, 117162 , 2026 2026
Grain boundary diffusion in compositionally complex alloys: A comprehensive review B Yadav, G Mohan Muralikrishna, M Vaidya, G Wilde, SV Divinski International Materials Reviews , 2025 2025 Citations: 5
Grain-and interphase boundary diffusion in eutectic AlCoCrFeNi2. 1 compositionally complex alloy H Zhang, GM Muralikrishna, A Akbari, H Rösner, BJ Tyler, SV Divinski, ... Acta Materialia 294, 121082 , 2025 2025 Citations: 15
The impact of non-equilibrium vacancies on mobilities and Kirkendall porosity formation in diffusion couples: Experiments and theory for the Cu–Fe–Ni system as a case study GM Muralikrishna, N Esakkiraja, J Kundin, F Hisker, J Berndt, S Klemme, ... Acta Materialia 292, 121035 , 2025 2025 Citations: 4
Grain boundary diffusion and segregation of Cr in Ni Σ11 (1̄13)[110] bicrystals: Decoding the role of grain boundary defects SV Sevlikar, GM Muralikrishna, D Gaertner, S Starikov, T Brink, ... Acta Materialia 278, 120229 , 2024 2024 Citations: 16
Demystifying the semiconductor‐to‐metal transition in amorphous vanadium pentoxide: the role of substrate/thin film interfaces ACM Esther, GM Muralikrishna, M Chirumamilla, MS Pinto, S Ostendorp, ... Advanced functional materials 34 (30), 2309544 , 2024 2024 Citations: 9
Grain boundary diffusion in a compositionally complex alloy: Interplay of segregation, precipitation and interface structures in a Ni–Cr–Mo alloy B Bian, L Söltzer, GM Muralikrishna, S Taheriniya, S Sen, KCH Kumar, ... Acta Materialia 269, 119803 , 2024 2024 Citations: 33
Microstructure stability and self-diffusion in the equiatomic HfScTiZr HCP multi-principal element alloy GM Muralikrishna, S Sen, SK Ayyappan, S Sankaran, K Guruvidyathri, ... Journal of Alloys and Compounds 976, 173196 , 2024 2024 Citations: 8
Coupling of alloy chemistry, diffusion and structure by grain boundary engineering in Ni–Cr–Fe B Bian, S Taheriniya, GM Muralikrishna, S Sen, C Gammer, I Steinbach, ... Acta Materialia 264, 119602 , 2024 2024 Citations: 17
Aluminium Matrix Composites: B2 Aluminide Strengthening D Srinu, Y Palguna, GM Muralikrishna, R Korala, K Srinivasarao, ... Transactions of Indian Institute of Metals , 2023 2023 Citations: 2
Kinetic and structural insights into the grain boundary phase transitions in Ni-Bi alloys B Bian, S Taheriniya, GM Muralikrishna, A Godha, SK Makineni, ... Acta Materialia 245, 118632 , 2023 2023 Citations: 14
Evolution of phase constitution with mechanical alloying and spark plasma sintering of nanocrystalline Al x CoCrFeNi ( x = 0, 0.3, 0.6, 1 mol) high-entropy alloys R Bhattacharya, M Annasamy, P Cizek, M Kamaraj, GM Muralikrishna, ... Journal of Materials Research 37 (4), 959-975 , 2022 2022 Citations: 28
Interface‐Driven Thermoelectric Switching Performance of VO + ‐Diffused Soda‐Lime Glass CME Alphonse, MM Garlapati, BJ Tyler, HF Arlinghaus, SV Divinski, ... physica status solidi (RRL)–Rapid Research Letters 15 (7), 2100077 , 2021 2021 Citations: 2
Tracer diffusion in the σ phase of the CoCrFeMnNi system J Zhang, GM Muralikrishna, A Asabre, Y Kalchev, J Mueller, B Butz, ... Acta Materialia 203, 116498 , 2021 2021 Citations: 49
Composition dependence of tracer diffusion coefficients in Fe–Ga alloys: A case study by a tracer-diffusion couple method GM Muralikrishna, B Tas, N Esakkiraja, VA Esin, KCH Kumar, IS Golovin, ... Acta Materialia 203, 116446 , 2021 2021 Citations: 31
Atomic transport in B2-ordered Al (Fe, Ni) alloys: Tracer-interdiffusion couple approach GM Muralikrishna, VA Esin, KN Kulkarni, BS Murty, G Wilde, SV Divinski Intermetallics 126, 106920 , 2020 2020 Citations: 16
Visualisation of stabilising particles at the gas-solid interface of metal foams V Pamidi, GM Muralikrishna, S Bhogi, K Georgy, B Muduli, ... Materials Letters 278, 128371 , 2020 2020 Citations: 4
Novel multicomponent B2-ordered aluminides: compositional design, synthesis, characterization, and thermal stability GM Muralikrishna, ACM Esther, K Guruvidyathri, P Watermeyer, ... Metals 10 (11), 1411 , 2020 2020 Citations: 24
Composition dependence of tracer diffusion coefficients in Fe-Ga alloys: a case study by a tracer-interdiffusion couple method GM Muralikrishna, B Tas, N Esakkiraja, V Esin, KC Kumar, IS Golovin, ... arXiv preprint arXiv:2008.12533 , 2020 2020
MOST CITED SCHOLAR PUBLICATIONS
High-entropy alloys by mechanical alloying: A review M Vaidya, GM Muralikrishna, BS Murty Journal of Materials Research 34 (5), 664-686 , 2019 2019 Citations: 563
Influence of Al content on thermal stability of nanocrystalline AlxCoCrFeNi high entropy alloys at low and intermediate temperatures MM Garlapati, M Vaidya, A Karati, S Mishra, R Bhattacharya, BS Murty Advanced Powder Technology 31 (5), 1985-1993 , 2020 2020 Citations: 71
Experimental assessment of the thermodynamic factor for diffusion in CoCrFeNi and CoCrFeMnNi high entropy alloys M Vaidya, GM Muralikrishna, SV Divinski, BS Murty Scripta Materialia 157, 81-85 , 2018 2018 Citations: 52
Microstructure and doping effect on the enhancement of the thermoelectric properties of Ni doped Dy filled CoSb 3 skutterudites V Trivedi, M Battabyal, P Balasubramanian, GM Muralikrishna, PK Jain, ... Sustainable Energy & Fuels 2 (12), 2687-2697 , 2018 2018 Citations: 50
Tracer diffusion in the σ phase of the CoCrFeMnNi system J Zhang, GM Muralikrishna, A Asabre, Y Kalchev, J Mueller, B Butz, ... Acta Materialia 203, 116498 , 2021 2021 Citations: 49
Influence of mechanically activated annealing on phase evolution in Al 0.3 CoCrFeNi high-entropy alloy R John, A Karati, MM Garlapati, M Vaidya, R Bhattacharya, D Fabijanic, ... Journal of Materials Science 54 (23), 14588-14598 , 2019 2019 Citations: 35
Grain boundary diffusion in a compositionally complex alloy: Interplay of segregation, precipitation and interface structures in a Ni–Cr–Mo alloy B Bian, L Söltzer, GM Muralikrishna, S Taheriniya, S Sen, KCH Kumar, ... Acta Materialia 269, 119803 , 2024 2024 Citations: 33
Composition dependence of tracer diffusion coefficients in Fe–Ga alloys: A case study by a tracer-diffusion couple method GM Muralikrishna, B Tas, N Esakkiraja, VA Esin, KCH Kumar, IS Golovin, ... Acta Materialia 203, 116446 , 2021 2021 Citations: 31
Evolution of phase constitution with mechanical alloying and spark plasma sintering of nanocrystalline Al x CoCrFeNi ( x = 0, 0.3, 0.6, 1 mol) high-entropy alloys R Bhattacharya, M Annasamy, P Cizek, M Kamaraj, GM Muralikrishna, ... Journal of Materials Research 37 (4), 959-975 , 2022 2022 Citations: 28
Novel multicomponent B2-ordered aluminides: compositional design, synthesis, characterization, and thermal stability GM Muralikrishna, ACM Esther, K Guruvidyathri, P Watermeyer, ... Metals 10 (11), 1411 , 2020 2020 Citations: 24
Tracer diffusion in ordered pseudo-binary multicomponent aluminides GM Muralikrishna, M Vaidya, BS Murty, SV Divinski, G Wilde Scripta Materialia 178, 227-231 , 2020 2020 Citations: 19
Coupling of alloy chemistry, diffusion and structure by grain boundary engineering in Ni–Cr–Fe B Bian, S Taheriniya, GM Muralikrishna, S Sen, C Gammer, I Steinbach, ... Acta Materialia 264, 119602 , 2024 2024 Citations: 17
Grain boundary diffusion and segregation of Cr in Ni Σ11 (1̄13)[110] bicrystals: Decoding the role of grain boundary defects SV Sevlikar, GM Muralikrishna, D Gaertner, S Starikov, T Brink, ... Acta Materialia 278, 120229 , 2024 2024 Citations: 16
Atomic transport in B2-ordered Al (Fe, Ni) alloys: Tracer-interdiffusion couple approach GM Muralikrishna, VA Esin, KN Kulkarni, BS Murty, G Wilde, SV Divinski Intermetallics 126, 106920 , 2020 2020 Citations: 16
Grain-and interphase boundary diffusion in eutectic AlCoCrFeNi2. 1 compositionally complex alloy H Zhang, GM Muralikrishna, A Akbari, H Rösner, BJ Tyler, SV Divinski, ... Acta Materialia 294, 121082 , 2025 2025 Citations: 15
Kinetic and structural insights into the grain boundary phase transitions in Ni-Bi alloys B Bian, S Taheriniya, GM Muralikrishna, A Godha, SK Makineni, ... Acta Materialia 245, 118632 , 2023 2023 Citations: 14
Preparation of nanocrystalline nickel oxide from nickel hydroxide using spark plasma sintering and inverse Hall-Petch related densification MB Ponnuchamy, GM Muralikrishna, VR Mannava, GS Reddy Ceramics International 44 (13), 15019-15023 , 2018 2018 Citations: 12
Demystifying the semiconductor‐to‐metal transition in amorphous vanadium pentoxide: the role of substrate/thin film interfaces ACM Esther, GM Muralikrishna, M Chirumamilla, MS Pinto, S Ostendorp, ... Advanced functional materials 34 (30), 2309544 , 2024 2024 Citations: 9
Microstructure stability and self-diffusion in the equiatomic HfScTiZr HCP multi-principal element alloy GM Muralikrishna, S Sen, SK Ayyappan, S Sankaran, K Guruvidyathri, ... Journal of Alloys and Compounds 976, 173196 , 2024 2024 Citations: 8