Report

Teaser, summary, work performed and final results

Periodic Reporting for period 2 - 3D2DPrint (3D Printing of Novel 2D Nanomaterials: Adding Advanced 2D Functionalities to Revolutionary Tailored 3D Manufacturing)

Teaser

Energy storage will be more important in the future than at any time in history. Climate change and the decreasing availability of fossil fuels require society to move towards sustainable and renewable resources.As a result, we are observing an increase in renewable energy...

Summary

Energy storage will be more important in the future than at any time in history. Climate change and the decreasing availability of fossil fuels require society to move towards sustainable and renewable resources.
As a result, we are observing an increase in renewable energy production from sun and wind, as well as the development of electric vehicles or hybrid electric vehicles with low CO2 emissions. Because the sun does
not shine during the night, wind does not blow on demand and we all expect to drive our car with at least a few hours of autonomy, energy storage systems are starting to play a larger part in our lives.

Batteries and supercapacitors are two very complementary types of energy storage devices.
Batteries store much higher energy densities; supercapacitors, on the other hand, hold one tenth of the electricity per unit of volume or weight as compared to batteries but can achieve much higher power densities.
Technology is currently striving to improve the power density of batteries and the energy density of supercapacitors.
To do so it is imperative to develop new materials, chemistries and manufacturing strategies.

3D2DPrint is developing micro-energy storage devices (both supercapacitors and batteries), technologies particularly relevant in the context of the emergent industry of micro-electro-mechanical systems and constantly downsized electronics.
We are using use novel two-dimensional (2D) nanomaterials obtained by liquid-phase exfoliation. This method offers a new, economic and easy way to prepare ink of a variety of 2D systems, allowing to produce wide device performance window through elegant and simple constituent control at the point of fabrication.
3D2DPrint is using our expertise and know-how to allow development of advanced AM methods to integrate dissimilar nanomaterial blends and/or “hybrids” into fully embedded 3D printed energy storage devices, with the ultimate objective to realise a range of products that contain the above described nanomaterials subcomponent devices, electrical connections and traditional micro-fabricated subcomponents (if needed) ideally using a single tool.

Objectives of the project are:
1. Development of 3D Printing Integration Models and Technologies
2. Synthesis, Purification and Liquid Phase Exfoliation of novel TMOs, LDHs, TMDs and MXenes
3. Characterisation of Liquid Phase Exfoliated 2D TMDs, LMCs, TMOs and MXenes
4. & 5. Supercapacitors and Batteries Fabrication
6. Electrochemical Characterisation of Electrodes and Performance Testing

Work performed

As described in the initial proposal we have been working on the following objectives:

Objective 1. Development of 3D Printing Integration Models and Technologies
Achievements:
- Development of 3D printed multi axis architectures
- Assembly of full supercaps and battery devices by vertically stacking of separately printed 3D architectures
- Development of 2.5 printing capabilities

Objective 2. Synthesis, Purification and Liquid Phase Exfoliation of novel TMOs, LDHs and TMDs
Achievements:
- Optimisation of the synthetic conditions for the preparation of TMOs, LDHs and MXenes (Investigation of different precursors and different wet synthetic parameters).
- Preliminary electrochemical characterisation of classically prepared electrodes
- Optimisation of the exfoliation conditions for LDHs, TMOs and MXenes (solvent selection – sonication regimes – centrifugation regimes)

Objective 3. Characterisation of Liquid Phase Exfoliated 2D TMDs, LMCs, TMOs and MXenes
Achievements:
- Full analytical characterisation of materials produced and exfoliated in objective 2 and development of high-throughput size characterisation method.
- State-of-the-art EM structural studies by aberration-corrected HRTEM and HAADF STEM
- Analytical characterisation of the exfoliated materials by atomic resolution EELS and EDX
- In-situ thermal, liquid and electrochemical characterisation of exfoliated materials on-going.

Objectives 4. & 5. Supercapacitors and Batteries Fabrication
Achievements:
- Fabrication of hierarchically structured 3D electrodes
- Manufacturing of electrodes by spraying for comparative performance evaluation
- Applying mediated drying from the liquid phase as a design tool for tuned device performance
- Assembly of hybrid electrodes based on TMDs and CNTs or graphene for batteries, LDHs, TMOs, MXenes and CNTs or graphene for supercapacitors.

Objective 6. Electrochemical Characterisation of Electrodes and Performance Testing
Achievements:
- Characterisation of the morphology of the fabricated electrodes
- Determination of the performance of the different devices fabricated under Objective 5 and 6
- Continuous feed-back to improve the performance
- Characterisation of the devices lifetime

The work plan has not been changed and we have adhered to the initial tasks described in the proposal.

Specific details as following:

Task 1: Passive devices – partial AM & functionally limited nanomaterial subset devices. (Months 1-9)
As envisaged in the proposal, this task has been running in parallel while Materials-part of the group has further developed the synthesis, exfoliation and design of novel 2D nanomaterial dispersions tuned for future AM jetting deposition technologies.
This task has been fully achieved. We bought (using ERC budget ad described in the budget section of the proposal) an aerosol jet printer and we have developed controlled deposition conditions to deposit the inks made by the Materials-part of the group.

Task 2: Passive devices – partial AM nanomaterial subset devices which are physically functional. (Months 10-18).
This task has been fully achieved (and resulted on one main specific publication: Stamping of Flexible, Coplanar Micro‐Supercapacitors Using MXene Inks, https://doi.org/10.1002/adfm.201705506).
For this part of the project we have used a Fused Deposition Modelling (FDM) semi-integrated tool by Voxel8 Inc, Somerville, MA, USA.

The work carried out inTasks 1, 2
have resulted in several high impact publications:
* Transparent, Flexible, and Conductive 2D Titanium Carbide (MXene) Films with High Volumetric Capacitance, https://doi.org/10.1002/adma.201702678
*Stamping of Flexible, Coplanar Micro‐Supercapacitors Using MXene Inks, https://doi.org/10.1002/adfm.201705506
*Graphene and MXene-based transparent conductive electrodes and supercapacitors, https://doi.org/10.1016/j.ensm.2018.05.003
*Additive-free MXene inks and direct printing of micro-supercapacitors, https://doi.org/10.1038/s41467-019

Final results

- Publications on high-impact journals achieved in all the areas above described
- 2 patents as described above.


We showed that two-dimensional titanium carbide or carbonitride nanosheets, known as MXenes, can be used as the conductive-binder in thick (up to 450 μm) silicon (Si)/MXene electrodes produced by a simple and scalable slurry-casting technique without the need of any other additives. The nanosheets knit into an interconnected metallic network, enable fast charge transport and provide good mechanical reinforcement for the thick electrode. Consequently, very high areal capacity (up to 23.3 mAh/cm2) on the anode side have been realized.
Nature Communication 2019

Direct printing of functional inks is critical for applications in diverse areas including electrochemical energy storage, smart electronics and healthcare. However, the available printable ink formulations are far from ideal. Either surfactants/additives are typically involved or the ink concentration is low, which add complexity to the manufacturing and compromises the printing resolution. Here, we demonstrate two types of two-dimensional titanium carbide (Ti3C2Tx) MXene inks, aqueous and organic in the absence of any additive or binary-solvent systems, for extrusion printing and inkjet printing, respectively. We show examples of all-MXene-printed structures, such as micro-supercapacitors, conductive tracks and ohmic resistors on untreated plastic and paper substrates, with high printing resolution and spatial uniformity. The volumetric capacitance and energy density of the all-MXene-printed microsupercapacitors are orders of magnitude greater than existing inkjet/extrusion-printed active materials. The versatile direct-ink-printing technique highlights the promise of additive-free MXene inks for scalable fabrication of easy-to-integrate components of printable electronics.
Nature Communication 2019


We demonstrated rapid production of flexible MSCs is demonstrated through a scalable, low-cost stamping strategy. Combining 3D-printed stamps with arbitrary shapes and 2D titanium carbide or carbonitride inks (Ti3C2Tx and Ti3CNTx, respectively, known as MXenes), flexible all-MXene MSCs with
controlled architectures are produced. The interdigitated Ti3C2Tx MSC exhibits high areal capacitance: 61 mF cm−2 at 25 μA cm−2 and 50 mF cm−2 as the current density increases by 32 fold. The Ti3C2Tx MSCs also showcase capacitive charge storage properties, good cycling lifetime, high energy and
power densities, etc. The production of such high-performance Ti3C2Tx MSCs can be easily scaled up by designing pad or cylindrical stamps, followed by a cold rolling process. Collectively, the rapid, efficient production of flexible all-MXene MSCs with state-of-the-art performance opens new exciting opportunities for future applications in wearable and portable electronics.
Advanced Functional Materials 2018

Website & more info

More info: https://chemistry.tcd.ie/cpam/.