A series of ionic-liquid-based nanofluids (ionanofluids) has been prepared by dispersing different wt % of alumina (Al 2 O 3 ) nanoparticles, covalently tethered with 1-nbutylionic liquid (IL) host. Thermophysical properties of the pure-IL and its nanofluids have been studied using transmission electron microscopy, differential scanning calorimetry (DSC) and vibrational spectroscopy. The tethered nanoadditives are dispersed uniformly within the IL host to form stable nanofluids over the entire range of nanoparticle weight fraction studied. Analysis of the heating rate dependent DSC data illustrates that the phase transition and fragility of the nanofluids can be effectively tuned by varying the content of the [b((MeO) 3 Sip)im][NTf 2 ]-tethered Al 2 O 3 nanoparticles. Moreover, the crystallization and melting transitions of the host can be completely avoided by dispersing merely 10 wt % of the nanoadditives. Analysis of the vibrational spectroscopy data reveals that the guest nanoadditives significantly affect both the relative orientation and the separation of the anion within the host IL through strong intermolecular interactions. The nonisothermal cold crystallization kinetics of the host IL and its nanofluids has been studied using different existing models. The concave downward temperature dependence of the effective activation energy, estimated from the isoconversional analysis of the crystallization data, has been successfully analyzed by standard nucleationbased kinetic model in combination with a power law model. The parameters evaluated from the combined analysis indicate that the tethered nanoparticles within the nanofluids act as heterogeneous nucleation agent, reducing the free energy barrier to nucleation. However, simultaneous large enhancement in diffusion contribution to the nucleation dominates and shifts the process toward higher temperature.

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energy-efficient, high-density data storage, and computing are the subject of intense research. [1-3] Memristors are promising building blocks for the next generation of electronics because they enable emerging highly efficient computing platforms such as in-memory and neuromorphic computing. [4,5] Of all genres of memristors, nonvolatile oxide materials are believed to be the most successful candidates in terms of their commercial potential. All the oxide memristors in use today are primarily based on filamentary mechanisms, which are inherently nonuniform [6-8] and thus exhibit performance variability and compromised device-yield. [9] In fact, the issue of nonuniformity and stochasticity is not only specific to oxides but is common in other genres of memristors like phase change memories, [10] nitrides, [11] or those working on metal-ion migration. [12-14] One of the problematic features inherent to any filamentary mechanism is electroforming, which is the first-time switching process involving dissolution, injection, and orientation of the active conducting atoms/ions into the dielectric layer. [7,15-17] The forming process usually requires much higher voltage and current than the reading/writing processes, resulting in One common challenge highlighted in almost every review article on organic resistive memory is the lack of areal switching uniformity. This, in fact, is a puzzle because a molecular switching mechanism should ideally be isotropic and produce homogeneous current switching free from electroforming. Such a demonstration, however, remains elusive to date. The reports attempting to characterize a nanoscopic picture of switching in molecular films show random current spikes, just opposite to the expectation. Here, this longstanding conundrum is resolved by demonstrating 100% spatially homogeneous current switching (driven by molecular redox) in memristors based on Ru-complexes of azo-aromatic ligands. Through a concurrent nanoscopic spatial mapping using conductive atomic force microscopy and in operando tip-enhanced Raman spectroscopy (both with resolution <7 nm), it is shown that molecular switching in the films is uniform from hundreds of micrometers down to the nanoscale and that conductance value exactly correlates with spectroscopically determined molecular redox states. This provides a deterministic molecular route to obtain spatially homogeneous, forming-free switching that can conceivably overcome the chronic problems of robustness, consistency, reproducibility, and scalability in organic memristors.

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