Periodic Reporting for period 1 - nanoOIPC (Surface characterization of nano-particle embedded organic ionic plastic crystals and ionic liquid using advance 3D high resolution optical and electrochemical imaging)
Période du rapport: 2016-10-12 au 2018-10-11
The nanoOIPC MSCA action objective was to investigate the electroactivity of nanoparticles (NPs) embedded in ionic liquids (ILs) or organic ionic plastic crystals (OIPCs) as nanocomposite materials and exploit them as soft electrode materials. There is an urgent need for these materials, e.g. for bioimplantation and energy storage. Several critical technical innovations are required to facilitate this advancement, particularly insight into the electroactivity-structure relationship.
ILs and OIPCs are both large organic salts. ILs have melting points below r.t. while OIPCs are solid at r.t. with melting points between 60-120°C. OIPCs are characterized by a plastic phase near r.t. that, when combined with embedded NPs, makes them excellent electroactive material candidates.
Our approach was to combine different multiscale, high-resolution electrochemical and optical imaging, to assess the electroactivity-structure relationship of nanocomposites operando, simultaneously. Through this research program, we pioneered electrochemical single metal NP impact detection at immiscible, micro liquid|liquid interfaces – both water|oil (w|o) and water|ionic liquid (w|IL).
We made several successful breakthroughs. First, we developed several low-cost ILs and OIPCs at high purity through solvent free and high yielding processes. Next, we discovered that residual metal reducing agent, LiBH4, used to form the NPs persists in the IL medium and grows to form inorganic nanocrystals (NCs). The growth of inorganic salts within these next generation electrolytes is a critical parameter that needs to be addressed and is rarely mentioned in the scientific literature. Our research program has strongly highlighted this fact but also shows the means with which it can be exploited to societies advantage.
Finally, this research program has been an immense success for both the Experienced Researcher (ER) and the host-organization (Université Paris Diderot, UPD). The exchange of knowledge (described below) has enhanced the perspectives of both the ER and UPD.
ILs and OIPCs are both large organic salts. ILs have melting points below r.t. while OIPCs are solid at r.t. with melting points between 60-120°C. OIPCs are characterized by a plastic phase near r.t. that, when combined with embedded NPs, makes them excellent electroactive material candidates.
Our approach was to combine different multiscale, high-resolution electrochemical and optical imaging, to assess the electroactivity-structure relationship of nanocomposites operando, simultaneously. Through this research program, we pioneered electrochemical single metal NP impact detection at immiscible, micro liquid|liquid interfaces – both water|oil (w|o) and water|ionic liquid (w|IL).
We made several successful breakthroughs. First, we developed several low-cost ILs and OIPCs at high purity through solvent free and high yielding processes. Next, we discovered that residual metal reducing agent, LiBH4, used to form the NPs persists in the IL medium and grows to form inorganic nanocrystals (NCs). The growth of inorganic salts within these next generation electrolytes is a critical parameter that needs to be addressed and is rarely mentioned in the scientific literature. Our research program has strongly highlighted this fact but also shows the means with which it can be exploited to societies advantage.
Finally, this research program has been an immense success for both the Experienced Researcher (ER) and the host-organization (Université Paris Diderot, UPD). The exchange of knowledge (described below) has enhanced the perspectives of both the ER and UPD.
The immiscible liquid|liquid interface is a unique platform that is often exploited for the assembly of NPs (Chem. Rev. 118 (2018) 3722); however, the use of NP modified electrified liquid|liquid interface is in its infancy. Our research program explored the capabilities of these interfaces and provided novel, breakthrough NP detection methodologies based on the liquid|liquid platform. Of particular interest is the water|ionic liquid (w|IL) interface, since NPs can be prepared within the IL with increased electroactivity owing to the absence of capping agents. Through this research program we pioneered electrochemical single NP detection through NP impacts at both the w|o and w|IL micro-interface; see Fig. 1 for the w|o Pt NP impact mechanism.
Investigative success is evidenced by 3 publications [Angew. Chem. 56 (2018) 13493; Chem. Rev. 118 (2018) 3722; Curr. Opin. Electrochem. 7 (2018) 200], with a fourth in review, and the ER being given an invited talk at 2018’s annual International Society of Electrochemistry Conference in Bologna (IT).
Through two synthetic methods we were able to generate both ILs and OIPCs in high yield and purity at low cost [Catal. Today 295 (2017) 89]. Subsequently, to investigate NP integration on OIPC/IL physicochemistry, Au and Pt NPs were prepared in IL and OIPC melt. Fig. 2 shows transmission electron microscopy images taken of Au and Pt NPs prepared in OIPC and IL. Using an electrolytic cell built in-house, the conductivity of IL-NP/OIPC-NP composites with different NP loadings, as well as thermal analysis, were used to investigate the effect of metal NPs on overall conductivity and phase transitions. Preliminary results suggest that with increased NP loading conductivity increases and solid-solid phase transitions merge and are reduced in intensity. More work is required however, one article is in preparation regarding the conducting/thermal influences of NP inclusion within ILs/OIPCs.
Our w|IL investigations showed that LiBH4, the reducing agent used to generate metal NPs within the IL phase, persisted in the IL phase and formed nanocrystals (NCs). Our high-resolution optical microscopies, such as dark-field and back-absorbing layer microscopy (BALM), allowed us to visualize these NCs, not possible with bright-field microscopies. The solubility of inorganic salts, like LiBH4, is rarely discussed but has wide implications on multiple applications, e.g. lithium ion batteries, industrial chemistry, and electrocatalysis. Therefore, a major outcome of this research was the discovery of reactive nanocrystalline inorganic salts formed within an IL phase. Moreover, LiBH4 is of use in two energy applications: H2 storage and in fuel cells. In this way, the LiBH4 NC-P66614NTf2 composite fluid could be used as a liquid fuel source. We also observed H2-in-IL bubble formation as a result of LiBH4 NC impacts. This research opens up an entirely new field of H2-in-IL micro-/nano-bubbles formation critical in water splitting for chemical fuel harvesting. Our strategy of incorporating opto-electronic techniques to observe operando H2 bubble formation, will be invaluable to research scientists in energy research. One publication (Electrochim. Acta. (2018) in review) and the ER’s invitation to speak at 2 other conferences (ECS fall meeting in Montreal, 2018; Chemistry Society of Canada annual meeting, summer 2019) have resulted from this work.
Investigative success is evidenced by 3 publications [Angew. Chem. 56 (2018) 13493; Chem. Rev. 118 (2018) 3722; Curr. Opin. Electrochem. 7 (2018) 200], with a fourth in review, and the ER being given an invited talk at 2018’s annual International Society of Electrochemistry Conference in Bologna (IT).
Through two synthetic methods we were able to generate both ILs and OIPCs in high yield and purity at low cost [Catal. Today 295 (2017) 89]. Subsequently, to investigate NP integration on OIPC/IL physicochemistry, Au and Pt NPs were prepared in IL and OIPC melt. Fig. 2 shows transmission electron microscopy images taken of Au and Pt NPs prepared in OIPC and IL. Using an electrolytic cell built in-house, the conductivity of IL-NP/OIPC-NP composites with different NP loadings, as well as thermal analysis, were used to investigate the effect of metal NPs on overall conductivity and phase transitions. Preliminary results suggest that with increased NP loading conductivity increases and solid-solid phase transitions merge and are reduced in intensity. More work is required however, one article is in preparation regarding the conducting/thermal influences of NP inclusion within ILs/OIPCs.
Our w|IL investigations showed that LiBH4, the reducing agent used to generate metal NPs within the IL phase, persisted in the IL phase and formed nanocrystals (NCs). Our high-resolution optical microscopies, such as dark-field and back-absorbing layer microscopy (BALM), allowed us to visualize these NCs, not possible with bright-field microscopies. The solubility of inorganic salts, like LiBH4, is rarely discussed but has wide implications on multiple applications, e.g. lithium ion batteries, industrial chemistry, and electrocatalysis. Therefore, a major outcome of this research was the discovery of reactive nanocrystalline inorganic salts formed within an IL phase. Moreover, LiBH4 is of use in two energy applications: H2 storage and in fuel cells. In this way, the LiBH4 NC-P66614NTf2 composite fluid could be used as a liquid fuel source. We also observed H2-in-IL bubble formation as a result of LiBH4 NC impacts. This research opens up an entirely new field of H2-in-IL micro-/nano-bubbles formation critical in water splitting for chemical fuel harvesting. Our strategy of incorporating opto-electronic techniques to observe operando H2 bubble formation, will be invaluable to research scientists in energy research. One publication (Electrochim. Acta. (2018) in review) and the ER’s invitation to speak at 2 other conferences (ECS fall meeting in Montreal, 2018; Chemistry Society of Canada annual meeting, summer 2019) have resulted from this work.
This research has significantly advanced NP detection methods, while at the same time providing valuable insight into NP reactivity. Facilitated by this research program and the ERs work, F. Kanoufi (supervisor) has prepared a series of demonstrations based in-part on these single NP entity studies for high school students. These lectures are part of the French Ministry of Educations: Année de Chimie 2019, which brings advanced university research into high schools to help foster student interest in the fields of Science, Technology, Engineering, and Mathematics (STEM) early in student life. These will be highly visually stimulating presentations that provide an enriching and entertaining experience for high school students to entice them into a STEM career. Programs like Année de Chimie are critical for the development of the next generation of scientists and researchers.
Through this research program, important scientific and technical training/knowledge was exchanged. The ER was able to introduce modern synthetic organic methods to the host group/institution, including NP preparation, as well as liquid|liquid electrochemistry and advanced computational methods. The PI (F. Kanoufi and G. Tessier) provided invaluable training to the ER in high resolution optical methods, electrochemical imaging, as well as a range of NP analytical techniques and data interpretation methods. A teaching tribune at ESPCI that was integrated into F. Kanoufi’s senior level electrochemistry course, allowed the ER to gain hands-on experience preparing lectures that will be invaluable for their future career. The ER also co-supervised 4 MSc students within the nanoOIPC research program, under F. Kanoufi’s overview, three of whom have gone on to pursue PhD positions in the fields of nano-material functionalization. This exceptional, well-rounded training made it possible for the ER to find a choice Assistant Professor position in their home country.
Through this research program, important scientific and technical training/knowledge was exchanged. The ER was able to introduce modern synthetic organic methods to the host group/institution, including NP preparation, as well as liquid|liquid electrochemistry and advanced computational methods. The PI (F. Kanoufi and G. Tessier) provided invaluable training to the ER in high resolution optical methods, electrochemical imaging, as well as a range of NP analytical techniques and data interpretation methods. A teaching tribune at ESPCI that was integrated into F. Kanoufi’s senior level electrochemistry course, allowed the ER to gain hands-on experience preparing lectures that will be invaluable for their future career. The ER also co-supervised 4 MSc students within the nanoOIPC research program, under F. Kanoufi’s overview, three of whom have gone on to pursue PhD positions in the fields of nano-material functionalization. This exceptional, well-rounded training made it possible for the ER to find a choice Assistant Professor position in their home country.