Showing posts with label energy storage. Show all posts
Showing posts with label energy storage. Show all posts

Thursday, June 29, 2023

Revolutionizing Fuel Cell Catalysts: Enhanced Durability and Performance with Platinum-Modified Tungsten Oxide Support

Breakthrough Study Utilizes Atomic Layer Deposition and Ar Plasma Treatment for Highly Robust Anode Catalysts in Polymer Electrolyte Membrane Fuel Cells

Key Findings:

1. Tungsten oxide (WO3) supported catalysts, enhanced through Ar plasma surface treatment and Pt nanoparticle deposition using atomic layer deposition (ALD), demonstrated significantly improved durability in diverse operating conditions compared to commercial Pt/C catalysts.

2. The use of WO3 as a catalyst support material, coupled with ALD-based Pt nanoparticle deposition, offers a promising approach for developing high-performance anode catalysts for polymer electrolyte membrane fuel cells (PEMFCs) with enhanced stability and performance.

In an article titled "Atomic layer deposited platinum on tungsten oxide support as high-performance hybrid catalysts for polymer electrolyte membrane fuel cells" Korean researchers discuss the development of a robust anode catalyst for polymer electrolyte membrane fuel cells (PEMFCs). The researchers aimed to address the performance degradation and carbon support corrosion issues commonly observed in PEMFCs under harsh operating conditions.

Graphical abstract

The study focused on using tungsten oxide (WO3) as a catalyst support material due to its ability to provide additional hydrogen ions and electrons through the decomposition of tungsten bronze (HxWO3) formed by the hydrogen spillover effect. The presence of HxWO3 also helped stabilize the cell potential by scavenging oxygen that infiltrates into the anode during start-up and shut-down situations. However, the low electrical conductivity of metal oxides can lead to initial performance degradation.

To overcome this limitation, the researchers performed Ar plasma surface treatment on the WO3 layer to enhance its electrical conductivity. This treatment, known as P-WO3, increased the density of electrons, enabling n-doped conduction. Next, platinum (Pt) nanoparticles were deposited on the P-WO3 support using atomic layer deposition (ALD). ALD allowed for the controlled deposition of Pt at the nanoscale, maximizing the catalytic activity with a minimal amount of precious metal.

The resulting Pt/P-WO3 catalyst exhibited significantly enhanced durability compared to commercial Pt/C catalysts under diverse operating conditions. It demonstrated improved performance and acted as a reversal-tolerant anode catalyst. The study highlights the potential of using WO3 as a support material and the effectiveness of the proposed fabrication method in developing high-performance catalysts for PEMFCs.

Overall, the article presents a novel approach to address the challenges associated with catalyst performance and carbon support corrosion in PEMFCs. By utilizing WO3 as a support material and incorporating Pt nanoparticles through ALD, the researchers achieved an improved and durable anode catalyst for PEMFCs.

The academic institutions behind the article are:

1. Department of Automotive Convergence, Korea University, Republic of Korea.

2. School of Mechanical Engineering, Korea University, Republic of Korea.

Source: Atomic layer deposited platinum on tungsten oxide support as high performance hybrid catalysts for polymer electrolyte membrane fuel cells - ScienceDirect

Sunday, June 11, 2023

Atomic Layer Deposition: Revolutionizing Battery Performance with Nanotech Precision

The ALD Process Offers Promising Solutions for Extended Battery Life and Enhanced Stability

In recent years, the demand for high-performance batteries has soared due to the growth of electric vehicles, renewable energy systems, and portable electronic devices. To meet these demands, researchers have turned to atomic layer deposition (ALD), a nanotechnology-based process that enables precise control of thin film materials at the atomic scale. ALD has shown great promise in boosting battery life and improving stability.

One of the major challenges in battery development is maintaining the structural integrity of electrodes during charge and discharge cycles. ALD addresses this by creating protective coatings on electrode materials, such as alumina or titania. These coatings prevent unwanted reactions and stabilize the solid electrolyte interphase (SEI), improving cycling stability.

ALD also improves electrolyte performance by creating hybrid organic-inorganic electrolytes with enhanced ionic conductivity and thermal stability. These electrolytes offer potential for safer and more efficient batteries, especially in high-temperature applications. Additionally, ALD enables the fabrication of advanced electrode materials with tailored nanostructures, boosting electrochemical performance.

Full article: Atomic Layer Deposition: The Nanotech Boost for Battery Life -

Tuesday, November 15, 2016

Special Issue: Atomic Layer Deposition for Energy and Environmental Applications

Here is a Special issue in Advanced Materials Interfaces: Atomic Layer Deposition for Energy and Environmental Applications LINK. The issue is guest edited by Neil P. Dasgupta, Liang Li, and Xueliang Sun.

The ALD Energy and Environment special issue has 11 invited research articles and 5 review articles  from leading ALD experts. The focus is on the following applications:
  • photo-voltaics
  • batteries
  • supercapacitors
  • photoelectrochemical cells
  • transparent electrodes
  • sensors
  • environmental barrier layers. 
The editors argue that ALD for Energy, judging by the number of publications the last 15 years (Web of Science database) is one of the faster growing application fields. Since we have a christian holiday tomorrow in Saxony I had some time to make a plot based on Google Scholar, which includes also patents. Yes you can see exactly the same growth trend. So folks ALD and Energy is coming and that is why you should check it out below (Embedded Twitter link to the journal).

Google Scholar year by year for "atomic layer deposition" AND energy. Obviously energy can also be used for binding energy etc. but I think the message is clear.

Monday, October 26, 2015

Atomic Layer Deposition (ALD) in Energy, Environment, and Sustainability

Atomic Layer Deposition (ALD) in Energy, Environment, and Sustainability

Figure. Schematic diagram of an ideal surface coating layer on active materials. Image provided by Xueliang Sun.

Guest Editors

Hongjin FanNanyang Technological University, Singapore
Yongfeng MeiFudan University, China
Mato KnezCIC nanoGUNE Research Center, Spain


The essential characteristics of an atomic layer deposition (ALD) reaction are the sequential self-limiting surface reactions to achieve conformal thin films with sub-monolayer thickness control. This advantage over other deposition processes renders a wide range of applications. While ALD was conventionally applied mainly in semiconductor electronic industry, recently, it is receiving increasing attention for wider applications in energy, environment, and sustainability research, with the advance in recipe development.
This focus collection will centre on the increasing importance of ALD techniques in developing innovative nanoscale materials, processes, devices, and systems relating to energy and environmental applications. Original and Review work detailing the development of energy nanomaterials and devices, including photovoltaics, batteries and supercapacitors, fuel cells, photocatalysts, and photoelectrochemical cells are solicited. Additionally developments in nanophotonics, including applications of ALD in new plasmonics, nanoscale laser, and metamaterials research are included. Interest of this collection also extends to innovations in chemical and biosensing using ALD, for example, organic pollution degradation, surface plasmon sensors, and quantum dot biomarkers.
The scope of this collection includes:
  • Fabrication and synthesis
  • Energy storage and conversion
  • Micro and nano-photonics
  • Sensor for environment and healthcare
  • Devices integration and reliability
We hope this issue provides a broad overview of the current state and guidance to the future.

Invited reviews

Applications of atomic layer deposition in solar cellsOPEN ACCESSWenbin Niu, Xianglin Li, Siva Krishna Karuturi, Derrick Wenhui Fam, Hongjin Fan, Santosh Shrestha, Lydia Helena Wong and Alfred Iing Yoong Tok2015 Nanotechnology 26 064001



The effect of ALD-grown Al2O3 on the refractive index sensitivity of CVD gold-coated optical fiber sensorsDavid J Mandia, Wenjun Zhou, Matthew J Ward, Howie Joress, Jeffrey J Sims, Javier B Giorgi, Jacques Albert and Seán T Barry2015 Nanotechnology 26 434002
Extremely high efficient nanoreactor with Au@ZnO catalyst for photocatalysisChung-Yi Su, Tung-Han Yang, Vitaly Gurylev, Sheng-Hsin Huang, Jenn-Ming Wu and Tsong-Pyng Perng2015 Nanotechnology 26 394001
Highly photocatalytic TiO2 interconnected porous powder fabricated by sponge-templated atomic layer depositionShengqiang Pan, Yuting Zhao, Gaoshan Huang, Jiao Wang, Stefan Baunack, Thomas Gemming, Menglin Li, Lirong Zheng, Oliver G Schmidt and Yongfeng Mei2015 Nanotechnology 26 364001
Control of the initial growth in atomic layer deposition of Pt films by surface pretreatmentJung Joon Pyeon, Cheol Jin Cho, Seung-Hyub Baek, Chong-Yun Kang, Jin-Sang Kim, Doo Seok Jeong and Seong Keun Kim2015 Nanotechnology 26 304003
Deposition of uniform Pt nanoparticles with controllable size on TiO2-based nanowires by atomic layer deposition and their photocatalytic propertiesChih-Chieh Wang, Yang-Chih Hsueh, Chung-Yi Su, Chi-Chung Kei and Tsong-Pyng Perng2015 Nanotechnology 26 254002
In-situ atomic layer deposition of tri-methylaluminum and water on pristine single-crystal (In)GaAs surfaces: electronic and electric structuresT W Pi, Y H Lin, Y T Fanchiang, T H Chiang, C H Wei, Y C Lin, G K Wertheim, J Kwo and M Hong2015 Nanotechnology 26 164001
Pd nanoparticles on ZnO-passivated porous carbon by atomic layer deposition: an effective electrochemical catalyst for Li-O2 batteryXiangyi Luo, Mar Piernavieja-Hermida, Jun Lu, Tianpin Wu, Jianguo Wen, Yang Ren, Dean Miller, Zhigang Zak Fang, Yu Lei and Khalil Amine2015 Nanotechnology 26 164003
Inert ambient annealing effect on MANOS capacitor memory characteristicsNikolaos Nikolaou, Panagiotis Dimitrakis, Pascal Normand, Dimitrios Skarlatos, Konstantinos Giannakopoulos, Konstantina Mergia, Vassilios Ioannou-Sougleridis, Kaupo Kukli, Jaakko Niinistö, Kenichiro Mizohata, Mikko Ritala and Markku Leskelä2015 Nanotechnology 26 134004
Impact of the atomic layer deposition precursors diffusion on solid-state carbon nanotube based supercapacitors performancesGiuseppe Fiorentino, Sten Vollebregt, F D Tichelaar, Ryoichi Ishihara and Pasqualina M Sarro2015 Nanotechnology 26 064002
Deposition of ultra thin CuInS2 absorber layers by ALD for thin film solar cells at low temperature (down to 150 °C)Nathanaelle Schneider, Muriel Bouttemy, Pascal Genevée, Daniel Lincot and Frédérique Donsanti2015 Nanotechnology 26 054001
Photocatalytic activity and photocorrosion of atomic layer deposited ZnO ultrathin films for the degradation of methylene blueYan-Qiang Cao, Jun Chen, Hang Zhou, Lin Zhu, Xin Li, Zheng-Yi Cao, Di Wu and Ai-Dong Li2015 Nanotechnology 26 024002
Influence of the oxygen plasma parameters on the atomic layer deposition of titanium dioxideStephan Ratzsch, Ernst-Bernhard Kley, Andreas Tünnermann and Adriana Szeghalmi2015 Nanotechnology 26 024003
Gas sensing properties and p-type response of ALD TiO2 coated carbon nanotubesCatherine Marichy, Nicola Donato, Mariangela Latino, Marc Georg Willinger, Jean-Philippe Tessonnier, Giovanni Neri and Nicola Pinna2015 Nanotechnology 26 024004
Air-Stable flexible organic light-emitting diodes enabled by atomic layer depositionYuan-Yu Lin, Yi-Neng Chang, Ming-Hung Tseng, Ching-Chiun Wang and Feng-Yu Tsai2015 Nanotechnology 26 024005
Uniform GaN thin films grown on (100) silicon by remote plasma atomic layer depositionHuan-Yu Shih, Ming-Chih Lin, Liang-Yih Chen and Miin-Jang Chen2015 Nanotechnology 26 014002
NiO/nanoporous graphene composites with excellent supercapacitive performance produced by atomic layer depositionCaiying Chen, Chaoqiu Chen, Peipei Huang, Feifei Duan, Shichao Zhao, Ping Li, Jinchuan Fan, Weiguo Song and Yong Qin2014 Nanotechnology 25 504001
Electrochemical synthesis of highly ordered nanowires with a rectangular cross section using an in-plane nanochannel arrayPhilip Sergelius, Josep M Montero Moreno, Wehid Rahimi, Martin Waleczek, Robert Zierold, Detlef Görlitz and Kornelius Nielsch2014 Nanotechnology 25 504002
Highly ordered and vertically oriented TiO2/Al2O3 nanotube electrodes for application in dye-sensitized solar cellsJae-Yup Kim, Kyeong-Hwan Lee, Junyoung Shin, Sun Ha Park, Jin Soo Kang, Kyu Seok Han, Myung Mo Sung, Nicola Pinna and Yung-Eun Sung2014 Nanotechnology 25 504003
Distinguishing plasmonic absorption modes by virtue of inversed architectures with tunable atomic-layer-deposited spacer layerYun Zhang, Kenan Zhang, Tianning Zhang, Yan Sun, Xin Chen and Ning Dai2014 Nanotechnology 25 504004
Cellulose nanofiber-templated three-dimension TiO2 hierarchical nanowire network for photoelectrochemical photoanodeZhaodong Li, Chunhua Yao, Fei Wang, Zhiyong Cai and Xudong Wang2014 Nanotechnology 25 504005
Atomic layer deposition of lithium phosphates as solid-state electrolytes for all-solid-state microbatteriesBiqiong Wang, Jian Liu, Qian Sun, Ruying Li, Tsun-Kong Sham and Xueliang Sun2014 Nanotechnology 25 504007
Nanostructured TiO2/carbon nanosheet hybrid electrode for high-rate thin-film lithium-ion batteriesS Moitzheim, C S Nimisha, Shaoren Deng, Daire J Cott, C Detavernier and P M Vereecken2014 Nanotechnology 25 504008

Saturday, October 24, 2015

Ferroelectric HfO2 enable giant pyroelectric energy conversion and highly efficient supercapacitors

A new application for energy harvesting and storage of ferroelectric hafnium oxide has been investigated and proven by researchers at NaMLab in Dresden, RWTHA Aachen and TU Munich, Germany. One major advantage of the use of hafnium oxide over other materials is the low cost of fabrication of these films while it has been proven feasible by existing semiconductor process technology like in ALD in CMOS high-k / metal gate and high-k node dielectric for DRAM capacitors.

To summarize this investigation:
  • Ferroelectric phase transitions in Si:HfO2 thin films yield giant pyroelectricity.
  • Si:HfO2 for highly efficient supercapacitors is first reported.
  • Si:HfO2 shows highest figures of merit for pyroelectric energy harvesting.
  • Si:HfO2 for electrocaloric cooling and infrared sensing is first reported.

Ferroelectric phase transitions in nanoscale HfO2 films enable giant pyroelectric energy conversion and highly efficient super capacitors

Temperature- and field-induced phase transitions in ferroelectric nanoscale TiN/Si:HfO2/TiN capacitors with 3.8 to 5.6 mol% Si content are investigated for energy conversion and storage applications. Films with 5.6 mol% Si concentration exhibit an energy storage density of ~40 J/cm3 with a very high efficiency of ~80% over a wide temperature range useful for supercapacitors. Furthermore, giant pyroelectric coefficients of up to −1300 µC/(m2 K) are observed due to temperature dependent ferroelectric to paraelectric phase transitions. The broad transition region is related to the grain size distribution and adjustable by the Si content. This strong pyroelectricity yields electrothermal coupling factors k2 of up to 0.591 which are more than one order of magnitude higher than the best values ever reported. This enables pyroelectric energy harvesting with the highest harvestable energy density ever reported of 20.27 J/cm3 per Olsen cycle. Possible applications in infrared sensing are discussed. Inversely, through the electrocaloric effect an adiabatic temperature change of up to 9.5 K and the highest refrigerant capacity ever reported of 19.6 J/cm3 per cycle is achievable. This might enable energy efficient on-chip electrocaloric cooling devices. Additionally, low cost fabrication of these films is feasible by existing semiconductor process technology.

Monday, September 15, 2014

Stanford engineering team has built a radio the size of an ant

A Stanford engineering team has built a radio the size of an ant, a device so energy efficient that it gathers all the power it needs from the same electromagnetic waves that carry signals to its receiving antenna.

Press release: A Stanford engineering team, in collaboration with researchers from the University of California, Berkeley, has built a radio the size of an ant, a device so energy efficient that it gathers all the power it needs from the same electromagnetic waves that carry signals to its receiving antenna – no batteries required.

Designed to compute, execute and relay commands, this tiny wireless chip costs pennies to fabricate – making it cheap enough to become the missing link between the Internet as we know it and the linked-together smart gadgets envisioned in the "Internet of Things."

"The next exponential growth in connectivity will be connecting objects together and giving us remote control through the web," said Amin Arbabian, an assistant professor of electrical engineering who recently demonstrated this ant-sized radio chip at the VLSI Technology and Circuits Symposium in Hawaii.

The tiny radio-on-a-chip gathers all the power it needs from the same electromagnetic waves that carry signals to its receiving antenna.

Much of the infrastructure needed to enable us to control sensors and devices remotely already exists: We have the Internet to carry commands around the globe, and computers and smartphones to issue the commands. What's missing is a wireless controller cheap enough to so that it can be installed on any gadget anywhere.

"How do you put a bi-directional wireless control system on every lightbulb?" Arbabian said. "By putting all the essential elements of a radio on a single chip that costs pennies to make."

Cost is critical because, as Arbabian observed, "We're ultimately talking about connecting trillions of devices."
More information:
A Power-Harvesting Pad-Less mm-Sized 24/60GHz Passive Radio with On-Chip Antennas, VLSI Technology and Circuits Symposium in Hawaii 2014.

Movie from (Stanford)

... and then just think what you could do with this radio chip on a MEMS mad bug like in the video below...

Researchers at Harvard and the Wyss Institute are developing a robotic bee that could be used to pollinate plants in the future. (

Friday, August 1, 2014

Perovskite pseudocapacitors for energy storage from Texas

Anion charge storage through oxygen intercalation in LaMnO3 perovskite pseudocapacitor electrodes

J. Tyler Mefford, William G. Hardin, Sheng Dai, Keith P. Johnston and Keith J. Stevenson
Nature Materials Volume: 13, Pages: 726–732 01 June 2014 



Perovskite oxides have attracted significant attention as energy conversion materials for metal–air battery and solid-oxide fuel-cell electrodes owing to their unique physical and electronic properties. Amongst these unique properties is the structural stability of the cation array in perovskites that can accommodate mobile oxygen ions under electrical polarization. Despite oxygen ion mobility and vacancies having been shown to play an important role in catalysis, their role in charge storage has yet to be explored. Herein we investigate the mechanism of oxygen-vacancy-mediated redox pseudocapacitance for a nanostructured lanthanum-based perovskite, LaMnO3. This is the first example of anion-based intercalation pseudocapacitance as well as the first time oxygen intercalation has been exploited for fast energy storage. Whereas previous pseudocapacitor and rechargeable battery charge storage studies have focused on cation intercalation, the anion-based mechanism presented here offers a new paradigm for electrochemical energy storage.

Sunday, May 25, 2014

Durable and safe cathode material enabled by ALD for the next-generation electric vehicles

Researchers at University of Colorado at Boulder, Brookhaven National Laboratory, and Seoul National University, has shown that a Al2O3 coating deposited by Atomic Layer Deposition (ALD) dramatically reduces the degradation in cell conductivity and reaction kinetics of commercially available cathode material used in today's state-of-art Li-ion batteries, lithium nickel–manganese–cobalt oxide Li[Ni1/3 Mn1/3Co1/3]O2 a.k.a. NMC.
According to the researchers the use of NMC cathodes for plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs), have not been possible so far because of: 
  • limited power performance (rate capability)
  • degradation in their capacity and cycle-life at high operation temperatures and voltages
The researches have developed a new durable ultra-thin Al2O3-ALD coating layer that also improves stability for the NMC at an elevated temperature. Furthermore, the experimental results suggest that a highly durable and safe cathode material enabled by atomic-scale surface modification can meet the demanding performance and safety requirements of next-generation electric vehicles.

The University of Colorado Boulder (also commonly referred to as CU-Boulder, CU, Boulder, or Colorado) is a public research university located in Boulder, Colorado, United States. It is the flagship university of the University of Colorado system and was founded five months before Colorado was admitted to the union in 1876. According to The Public Ivies: America's Flagship Public Universities (2001), it is considered one of the thirty "Public Ivy League" schools. (Source: Wikipedia, Picture :  The  Campus of University of Colorado Boulder,
The work has been funded by by National Science Foundation (USA), Department of Energy (USA), and Ministry of Knowledge Economy (KOR).
Results have been published in the article below in the Journal of Power Sources:
Ji Woo Kim, Jonathan J. Travis, Enyuan Hu, Kyung-Wan Nam, Seul Cham Kim, Chan Soon Kang, Jae-Ha Woo, Xiao-Qing Yang, Steven M. George, Kyu Hwan Oh, Sung-Jin Cho, Se-Hee Lee
Journal of Power Sources, Volume 254, 15 May 2014, Pages 190–197
Abstract: Electric-powered transportation requires an efficient, low-cost, and safe energy storage system with high energy density and power capability. Despite its high specific capacity, the current commercially available cathode material for today's state-of-art Li-ion batteries, lithium nickel–manganese–cobalt oxide Li[Ni1/3 Mn1/3Co1/3]O2 (NMC), suffers from poor cycle life for high temperature operation and marginal rate capability resulting from irreversible degradation of the cathode material upon cycling. Using an atomic-scale surface engineering, the performance of Li[Ni1/3Mn1/3Co1/3]O2 in terms of rate capability and high temperature cycle-life is significantly improved. The Al2O3 coating deposited by atomic layer deposition (ALD) dramatically reduces the degradation in cell conductivity and reaction kinetics. This durable ultra-thin Al2O3-ALD coating layer also improves stability for the NMC at an elevated temperature (55 °C). The experimental results suggest that a highly durable and safe cathode material enabled by atomic-scale surface modification could meet the demanding performance and safety requirements of next-generation electric vehicles.
More interesting publications from The Electrochemical Energy Laboratory at University of Colorado at Boulder  on high performance materials for sustainable energy applications :  batteries, supercapacitors, fuel cells, electrochromic winodws, and photoelectrochemical devices can be found here:

Monday, May 19, 2014

Vanderbilt University - A Multifunctional Load-Bearing Solid-State Supercapacitor

"The biggest problem with designing load-bearing supercaps is preventing them from delaminating," said Westover. "Combining nanoporous material with the polymer electrolyte bonds the layers together tighter than superglue."
Andrew S. Westover, John W. Tian, Shivaprem Bernath, Landon Oakes, Rob Edwards, Farhan N. Shabab, Shahana Chatterjee, Amrutur V. Anilkumar, and Cary L. Pint
Nano Lett., DOI: 10.1021/nl500531r, Publication Date (Web): May 13, 2014

Abstract: A load-bearing, multifunctional material with the simultaneous capability to store energy and withstand static and dynamic mechanical stresses is demonstrated. This is produced using ion-conducting polymers infiltrated into nanoporous silicon that is etched directly into bulk conductive silicon. This device platform maintains energy densities near 10 W h/kg with Coulombic efficiency of 98% under exposure to over 300 kPa tensile stresses and 80 g vibratory accelerations, along with excellent performance in other shear, compression, and impact tests. This demonstrates performance feasibility as a structurally integrated energy storage material broadly applicable across renewable energy systems, transportation systems, and mobile electronics, among others.

Improved supercapacitors using ruthenium oxide RGM foam by University of California

As reported today by Sean Nealon, UC Riverside, Researchers at the Univ. of California, Riverside have developed a novel nanometer scale ruthenium oxide anchored nanocarbon graphene foam architecture that improves the performance of supercapacitors, a development that could mean faster acceleration in electric vehicles and longer battery life in portable electronics.

Read the full story here in the R&D Mag or check out the original OPEN ACCESS publication bellow:
Hydrous Ruthenium Oxide Nanoparticles Anchored to Graphene and Carbon Nanotube Hybrid Foam for Supercapacitors
Wei Wang, Shirui Guo, Ilkeun Lee, Kazi Ahmed, Jiebin Zhong, Zachary Favors, Francisco Zaera, Mihrimah Ozkan & Cengiz S. Ozkan          
Scientific Reports 4, Article number: 4452 doi:10.1038/srep04452, 25 March 2014

Abstract: In real life applications, supercapacitors (SCs) often can only be used as part of a hybrid system together with other high energy storage devices due to their relatively lower energy density in comparison to other types of energy storage devices such as batteries and fuel cells. Increasing the energy density of SCs will have a huge impact on the development of future energy storage devices by broadening the area of application for SCs. Here, we report a simple and scalable way of preparing a three-dimensional (3D) sub-5 nm hydrous ruthenium oxide (RuO2) anchored graphene and CNT hybrid foam (RGM) architecture for high-performance supercapacitor electrodes. This RGM architecture demonstrates a novel graphene foam conformally covered with hybrid networks of RuO2 nanoparticles and anchored CNTs. SCs based on RGM show superior gravimetric and per-area capacitive performance (specific capacitance: 502.78 F g−1, areal capacitance: 1.11 F cm−2) which leads to an exceptionally high energy density of 39.28 Wh kg−1 and power density of 128.01 kW kg−1. The electrochemical stability, excellent capacitive performance, and the ease of preparation suggest this RGM system is promising for future energy storage applications.

(a) Schematic illustration of the preparation process of RGM nanostructure foam. SEM images of (b–c) as-grown GM foam (d) Lightly loaded RGM, and (e) heavily loaded RGM. (Source : article above)

Check out the performance in this Ragone plot - Woah - pretty high energy density material!

(a) EIS plots and (b) high frequency region EIS plots of GM, RGM, a control sample (RuO2 nanoparticles only), respectively. (c) Ragone plot related to energy densities and power densities of the packaged whole cell RGM SC, GM SC, RuO2 nanoparticles SC, hydrous ruthenium oxide (RuO2)/graphene sheets composite (GOGSC), RuO2 nanowire/single walled carbon nanotube (SWNT) hybrid film. (Source: articlew above)

Friday, May 16, 2014

Towards all solid-state 3D thin-film batteries for durable and fast storage by imec

An excellent overview on all solid-state 3D thin-film batteries where Philippe Vereecken principal scientist at imec, and associate professor at KU Leuven explains "One way to make Li-ion batteries more durable, safer, smaller and in particularly faster, is a transition towards all solid-state 3D thin-film Li-ion batteries." The article can be find on page 30 in the May 2014 issue of Solid State Technology. UPDATE: this paper is also available here as html Solid State Technology.
Schematic of a planar (a) and 3D thin-film (b) battery with the following stack: current collector/ electrode/solid electrolyte/electrode/current collector. (Source: Solid State Technology)
ALD processes for solid state lithium batteries has been and is an active field of research at Oslo and Helsinki University. Below is a recent review from Ola Nilsen et al giving a great overview on the ALD precursor and processes that have been investigated so far.

Ola Nilsen, Ville Miikkulainen, Knut B. Gandrud, Erik Østreng, Amund Ruud, Helmer Fjellvag
Volume 211, Issue 2, pages 357–367, February 2014

The lithium ion battery concept is a promising energy storage system, both for larger automotive systems and smaller mobile devices. The smallest of these, the microbatteries, are commonly based on the all-solid state concept consisting of thin layers of electroactive materials separated by a solid state electrolyte. The fact that solid state electrolytes are required puts rather severe constraints on the materials in terms of electronic and ionic conductivity, as well as lack of pinholes otherwise leading to self-discharge. The atomic layer deposition (ALD) technology is especially suitable for realization of such microbatteries for the Li-ion technology. ALD has an inherent nature to deposit conformal and pinhole free layers on complex geometrical shapes, an architecture most commonly adopted for microbattery designs. The current paper gives an overview of ALD-type deposition processes of functional battery materials, including cathodes, electrolytes, and anodes with the aim of developing all-solid-state batteries. Deposition of Li-containing materials by the ALD technique appears challenging and the status of current efforts is discussed.