Fei Zheng and Weijian Chen's paper, Triggering the Passivation Effect of Potassium Doping in Mixed-Cation Mixed-Halide Perovskite by Light Illumination, has been accepted by Advanced Energy Materials [Link]. Tongle, Kenneth, Fuzhi, Yibing, Patrick and Tak are listed as co-authors. Xiaoming and Baohua are the corresponding authors.
In this work, it is demonstrated that illumination is essential to trigger the passivation effect of K+ by forming KBr-like compounds, leading to the elimination of interface trapping defects and suppression of mobile ion migration, thus resulting in improved power conversion efficiency and negligible current-voltage hysteresis of solar cells. This work provides novel insight into the hysteresis suppression upon K+ doping and highlights the significance of light illumination when using this protocol.
Congratulations Fei and Weijian!
A new state-of-the-art research centre, Centre for Translational Atomaterials (CTAM), is established. CTAM will lead the conception, design, characterisation, theoretical modelling and development of new transformative technologies based on atomic materials, such as graphene and graphene family materials and other two-dimensional materials.
Centre Director Professor Baohua Jia and Deputy Director Associate Professor Chenghua Sun, together with the Program Leaders Professor Xiaodong Huang, Professor Alan Lau, Professor Paul Stoddart, Professor Feng Wang and Deputy Program Leader Dr Rosalie Hocking, aim to develop the new centre as a world-leader in innovative and emergent materials, with strong ties to fundamental science and industrial applications. The centre will directly contribute to the development of new generation atomic materials and technologies, which have the potential to create new industries and businesses in Australia, and worldwide.
As the core component part, LNI group is dedicated to contribute to the future successes of our new research Centre for Translational Atomaterials.
LNI group will host ICNASA at Swinburne University of Technology on 4-5 July 2019 [Link]. This conference focuses on the most recent advances in the fields of micro/nano/atomic-materials and optoelectronics, especially the new ideas and concepts in modelling, synthesis, fabrication and testing of new materials, structures, devices and systems, and their applications. It provides a global forum to exchange knowledge on nano and atomic materials, engineering, manufacturing and industrialisation.
Zhixing Gan's paper, The Dominant Energy Transport Pathway in Halide Perovskites: Photon Recycling or Carrier Diffusion?, has been accepted by Advanced Energy Materials [Link]. Weijian, Chunhua, Shuang, Guiyuan, Kenneth and Ghiggino are listed as co-authors. Xiaoming and Baohua are the corresponding authors.
In this work, a comparison of 3D bulk CH3NH3PbBr3 single crystal to 2D perovskite by depth-resolved two-photon PL spectra reveals the contribution of carrier diffusion on energy transport at a distance beyond diffusion length is constantly negligible, though the carrier diffusion indeed exists in the 3D crystal. The investigation resolves the fundamental confusion and debate surrounding the issue and provides significant insights into carrier kinetics in perovskites, which is important for future developments in solar cells and other optoelectronic devices.
Han Lin's paper, A 90-nm-thick graphene metamaterial for strong and extremely broadband absorption of unpolarized light, has been accepted by Nature Photonics [Link]. Björn C. P. Sturmberg, Keng-Te, Yunyi, Xiaorui and Teck are listed as co-authors. C. Martijn de Sterke and Baohua are the corresponding authors.
In this work, the authors experimentally dem-onstrate a 12.5 cm2, 90-nm-thick graphene metamaterial with approximately 85% absorptivity of unpolarized, visible and near-infrared light covering almost the entire solar spectrum (300-2,500 nm). The metamaterial consists of alternating graphene and dielectric layers; a grating couples the light into waveguide modes to achieve broadband absorption over incident angles up to 60. The very broad spectral and angular responses of the absorber are ideal for solar thermal applications, as they illustrate by showing heating to 160 C in natural sunlight. These devices open a novel approach to applications of strongly absorbing large-area photonic devices based on two-dimensional materials.
Tieshan Yang's paper, Fundamental Transport Mechanisms and Advancements of Graphene Oxide Membranes for Molecular Separation, has been accepted by Chemistry of Materials [Link]. Han and Kian Ping are listed as co-authors. Baohua is the corresponding author.
In this review, the mechanisms, i.e., in-plane pores (defects), interlayer spacing, and functional group assisted molecular separation, of selective molecular transport through GO membranes are summarized. In addition, preparation and interlayer spacing tuning strategies of GO membranes are provided. This timely review aims to present the latest advancements in both the theoretical and experimental demonstration of GO membranes for molecular separation. Moreover, current challenges and emerging perspectives of GO membranes for separation are also discussed.
Yunyi Yang's paper, Graphene-Based Multilayered Metamaterials with Phototunable Architecture for on-Chip Photonic Devices, has been accepted by ACS Photonics [Link]. Han, Baoyue, Yinan, Xiaorui, Aimin and Minghui are listed as co-authors. Baohua is the corresponding author.
In this work, the experimental demonstration of the phototunable graphene-based multilayered metamaterials on diverse substrates by a transfer-free, solution-phase deposition method is presented. This graphene-based metamaterial provides a new experimental platform for broad applications in on-chip integrated photonic, biomedical, and microfluidic devices.
Mr.Yunyi Yang has been awarded the degree of Doctor of Philosophy (Science) in January 2019. Yunyi started his PhD study in September 2014 under the supervision of Professor Baohua Jia. The title of his thesis is " 3D multilayer graphene oxide thin film platform for functional devices".
Congratulations Dr. Yang!
Zhixing Gan's paper, External stokes shift of perovskite nanocrystals enlarged by photon recycling, has been accepted by Applied Physics Letters [Link]. Weijian, Lin Yuan, Guiyuan, Chunhua, Shujuan are listed as co-authors. Xiaoming and Baohua are the corresponding authors.
In this work, the authors found that photon recycling significantly contributes to the external Stokes shift of perovskite NCs, in particular for the ultra-small sizes with strong QCE. This finding will add to the growing fundamental physical understanding of perovskites, which is of great interest due to their applications in photovoltaics and other fields.
Professor Baohua Jia and Dr. Keng-Te Lin were awarded $340,000 for a 2018 ARC Discovery Project to develop an environmentally-friendly solution for efficient thermal energy manipulation;
Professor Saulius Juodkazis, Dr Xiaoming Wen, and Professor David Moss were awarded $450,000 for a 2018 ARC Discovery project to develop a new standard in solar energy conversion efficiency.
Tieshan Yang's paper, Anisotropic Third-Order Nonlinearity in Pristine and Lithium Hydride Intercalated Black Phosphorus, has been accepted by ACS Photonics [Link]. Ibrahim, Han, Yang, Sherman, Scott, Kian are listed as co-authors. Baohua is the corresponding author.
In this work, the authors measured the third-order nonlinear optical responses in exfoliated black phosphorus (BP) and in lithium hydride intercalated BP (LiH-BP) flakes using polarization-resolved microscopic femtosecond Z-scan techniques. Highly anisotropic polarization-dependent Kerr nonlinearities of both BP and LiH-BP flakes were observed. The strong nonlinear and anisotropic optical responses of BP and LiH-BP indicate the great potential of these materials in nonlinear photonics device applications.
Zhixing Gan's paper, Engineering the Carrier Dynamics of g-C3N4 by Rolling up the Planar Sheets to Nanotubes via Ultrasonic Cavitation, has been accepted by Nanoscale [Link]. Baohua is the corresponding author. In this work, a simple and clean ultrasonic method is developed to curve the 2D g-C3N4 sheets to 1D nanotubes. And the carrier dynamics of the g-C3N4 sheets nanotubes are studied by time-resolved PL spectra.
Yunyi Yang's paper, Enhanced four-wave mixing in waveguides integrated with graphene oxide, has been published online by APL Photonics [Link] as featured article and highlighted on the journal's home page. Jiayang, Xingyuan, Yao, Sai, Brent, Roberto are listed as co-authors. Baohua and David are the corresponding authors.
In this study, the authors demonstrate enhanced four-wave mixing (FWM) in doped silica waveguides integrated with graphene oxide (GO) layers. They showed theoretically that for different waveguide geometries an enhancement in FWM efficiency of ~20 dB can be obtained in the doped silica waveguides and more than 30 dB in silicon nanowires and slot waveguides. This demonstrates the effectiveness of introducing GO films into integrated photonic devices in order to enhance the performance of nonlinear optical processes. .
Chunhua Zhou's paper, Illumination Induced Halide Segregation in Gradient Bandgap Mixed-Halide Perovskite Nanoplatelets, has been accepted by Advanced Optical Materials [Link]. Qingdong, Weijian, Zhixing, James, Qiaoliang are listed as co-authors. Xiaoming and Baohua are the corresponding authors.
In this study, the authors develop a method to fabricate gradient bandgap perovskites with designed energy funneling, and also provides significant insight into the halide segregation in such special perovskites, which greatly benefits their future optoelectronic applications.
LNI group member, Dr Xuewen Wang has won the $5,000 ANN Overseas Travel Fellowship to support his visit to Radboud University, Nijmegen, the Netherlands for a period of three months. ANN supports the nanotechnology community by making funding support available to postgraduate students and early career researchers (within 5 years of award of PhD degree) for travel and accommodation expenses associated with ANFF Short Term Visits, Short term visits and Long Term Visits, within Australia including collaborative visits to Industry. ANN also offers postgraduate students and early career researchers (within 5 years of award of PhD degree) Overseas Travel Fellowships to support for travel and accommodation expenses associated with research visits of up to 3 months duration at collaborating research institutions and industry overseas.
LNI group members, Tieshan Yang has won the prestigious 2018 IONS KOALA Travel Grant up to the value of 200 AUD. The IONS Conference on Optics, Atoms, and Laser Applications (KOALA) is an annual conference held in Australia and New Zealand sponsored by The Optical Society (OSA). The 11th instalment of IONS KOALA is being co-hosted by the OSA student chapters at Macquarie University and the University of Sydney. With the support of many organisations, KOALA brings together research students in physics from all around the world
LNI group members, Yachu Zhang has won the prestigious 2018 Swinburne Research Student Photography & Image Competition with his "Broken bridge structure of reduced graphene oxide". All entries were judged on aesthetics, creativity and relevance to research by a professional panel.
Shuo Li's paper, On-Demand Design of Tunable Complete Photonic Band Gaps based on Bloch Mode Analysis, has been accepted by Scientific Reports [Link]. Han, Fei, David are listed as co-authors. Xiaodong and Baohua are the corresponding authors.
In this study, the authors present an analytical design method for achieving high-order two-dimensional photonic crystals with tunable photonic band gaps on-demand. Based on the Bloch mode analysis for periodic structures, the authors are able to determine the geometric structure of the unit cell that will realize a nearly optimal photonic band gap for one polarization between the appointed adjacent bands. More importantly, this method generates a complete bandgap for all polarizations, with frequencies tuned by the number of photonic bands below the gap. The lowest dielectric contrast needed to generate a photonic band gap, as well as conditions for generating complete bandgaps, are investigated. The work first highlights the systematic approach to complete photonic band gaps design based on Bloch mode analysis. The physical principles behind our work are then generalized to other photonic lattices.
Guiyuan Cao's paper, An accurate design of graphene oxide ultrathin flat lens based on Rayleigh-Sommerfeld theory, has been accepted by Opto-Electronic Advances [Link]. Xiaosong, Han are listed as co-authors. Baohua is the corresponding authors.
In this study, the authors develop a lens design method based on the Rayleigh-Sommerfeld (RS) diffraction theory that is able to unambiguously determine the radii of each ring without the optimization process for the first time. More importantly, the RS design method is able to accurately design GO lenses with arbitrary NA and focal length. Their design is experimentally confirmed by fabricating high NA GO lenses with both short and long focal lengths. Compared with the conventional Fresnel design methods, the differences in ring positions and the resulted focal length are up to 13.9% and 9.1%, respectively. The method can be further applied to design high performance flat lenses of arbitrary materials given the NA and focal length requirements, including metasurfaces or other two-dimensional materials.
LNI group members, Dr Xiaoming Wen and Dr Han Lin have won the prestigious FSET Research Travel Grants for round 1 2018. Awards are made in the range $1000 - $2000 to support their travel and networking opportunities.
Congratulations Xiaoming and Han!
Fei Zheng's paper, Slow Response of Carrier Dynamics in Perovskite Interface upon Illumination, has been accepted by ACS Applied Materials & Interfaces [Link]. Weijian is listed as a co-author. Xiaoming and Baohua are the corresponding authors.
In this study, the authors investigated the slow variation of photogenerated carrier dynamics in (FAPbI3)0.85(MAPbBr3)0.15 perovskite interface under continuous illumination. Different response behaviours of carrier dynamics in perovskite interfaces with and without hole transporting layer, Spiro-OMeTAD (Spiro), were systematically studied by time-dependent steady-state and time-resolved photoluminescence (PL). It was demonstrated that light-induced defect curing process is dominantly responsible for the carrier dynamic evolution for perovskite interface without Spiro, while both defect curing process and mobile ions migration should be account for the dynamic response of perovskite interface contact with Spiro. This research work can faithfully highlight the strong correlation of slow photo-response behaviours of perovskite interface with both light-induced defect curing and ion migration process, providing novel implications into the physical mechanism for the slow variation of PSCs performance under working condition.
Xiaoming's paper, The Role of Surface Recombination in Halide Perovskite Nanoplatelets, has been accepted by ACS Applied Materials & Interfaces [Link]. Weijian, Tieshan, Chunhua, Han are listed as co-authors. Xiaoming, Baohua and David are the corresponding authors.
The paper, using time-resolved micro-spectroscopy along with modelling, investigates charge carrier recombination dynamics in halide perovskite CH3NH3PbI3 nanoplatelets with thicknesses from ~ 20 - 200nm, ranging from much less to comparable to the carrier diffusion length. It shows that surface recombination plays a stronger role in thin perovskite nanoplatelets, significantly decreasing photoluminescence (PL) efficiency, PL decay lifetime, and photo-stability. This work provides a comprehensive understanding of the role of surface recombination and charge carrier dynamics in thin perovskite platelets and reveals valuable insights useful for applications in photovoltaics and photonics.
Ph.D candidate Mr. Yunyiyang's dissertation has been dispatched to the examiners.
Minister Birmingham has also announced the new ARC Training Centre in Surface Engineering for Advanced Materials (SEAM), led by Distinguished Professor Chris Berndt, to be awarded $6,654,410 over five years. The centre brings together research leaders across all career stages, including Professor Peter Kingshott, Professor Baohua Jia, Dr Rosalie Hocking, Professor Guoxing Lu, Professor Saulius Juodkazis, Professor Xiaodong Huang, Associate Professor Scott Wade, Dr Andrew Ang, and Dr James Wang.
The ARC Training Centre in Surface Engineering for Advanced Materials aims to provide pathways for job creation and a high quality workforce in manufacturing. Surface engineering for advanced materials is a core need in all manufacturing sectors and controls the efficiency, productivity and sustainability of Australian industry. ($4.89M).
Partners: Brenco Aerospace Pty. Ltd.; Kremford (Vic) Pty Ltd; Laserbond Limited; Romar Engineering Pty Ltd; Ruag Australia Pty Ltd; Titomic Pty Ltd; Sutton Tools Proprietary Limited; United Surface Technologies Pty. Ltd.; SCG Chemicals Co. Ltd; Ningbo Flo Optical Technology Development Co.,Ltd; Australian Nuclear Science And Technology Organisation; Commonwealth Scientific And Industrial Research Organisation; DMTC Limited.
Blanca's paper, Beyond Phototherapy: Recent Advances in Multifunctional Fluorescent Nanoparticles for Light-Triggered Tumor Theranostics, has been accepted by Advanced Functional Materials [Link]. Baohua is listed as a co-author. This article reviews the different approaches for in vivo tumor theranostics, highlighting their advantages and limitations, and provides a critical analysis of the current state of the ﬁeld.
"We talk about recent (last 5 years) advances on multifunctional nanoparticles for image-guided tumor therapy. This was a toooooough thing to put together but I am pretty proud of how it looks!!", said Blanca, the first author.
Shuangyang's paper, Template-Free Synthesis of High-Yield Fe-Doped Cesium Lead Halide Perovskite Ultralong Microwires with Enhanced Two-Photon Absorption, has been accepted by The Journal of Physical Chemistry Letters [Link]. Tieshan, Zhixing, Weijian, Xiaoming are listed as co-authors. Baohua is the corresponding author.
This article demonstrates the successful synthesis of high-yield Fe-doped cesium lead halide perovskite ultralong microwires, which have a diameter up to 5 microns and lengths up to millimeters, via an anti-solvent vapor-assisted template-free method. Super-high nonlinear absorption and high-quality optical properties have been characterised, indicating its promising applications in spin related optical switching and optical limiting devices.
Fei Zheng, Chunhua and Baohua’s collaborative paper, A biomimetic supramolecular approach for charge transfer between donor and acceptor chromophores with aggregation-induced emission, has been accepted by Chemistry A European Journal [Link].
In this work, an electron-donating chromophore and an electron-accepting chromophore based on TPE have been designed and synthesised, demonstrating a convenient approach to fabricate a supra molecular charge transfer system using an AIE donor and acceptor.
Xuewen's paper, Recent Advances on Optical Vortex Generation, has been accepted by Nanophotonics. Yao Liang is one of the co-authors and Baohua is the corresponding author.
This article reviews recent progress leading to the generation of optical vortex beams. Different approaches for optical vortex generation by discrete components and laser cavities have been summarised. Recent progress on vortex lasing has also been introduced, including vortex beam generation from the output of bulk lasers by modification of conventional laser cavities with phase elements and from integrated on-chip microlasers. The advanced technology and approaches on design and nanofabrications enable multiple vortex beams generation from a single device via multiplexing, multicasting and vortex array, open up opportunities for applications on parallel data processing, information encoding/ decoding, communication and micromanipulations.
Mr. Yunyi Yang has won the HDR Publication Award. This grant aims to encourage HDR students to prepare research publications without jeopardising the progress towards thesis completion.
Ms. Shuo Li has been awarded the degree of Doctor of Philosophy (Science) in June 2018. Shuo started her PhD study in August 2014 under the supervision of Professor Baohua Jia. The title of her thesis is "Physical Design of Periodic Structures: from Photonic Crystals to Phononic Crystals".
Congratulations Dr. Li!
Shao Ing's paper, “Towards enhanced energy density of graphene-based supercapacitors: Current status, approaches, and future directions”, has been accepted by the Journal of Power Sources [Link]. Shao Ing is a Joint PhD student from Sarawak campus. Han is one of the co-authors and Baohua is the corresponding author.
This paper discusses current status of graphene-based supercapacitors in energy storage market. Approaches to high energy density graphene-based supercapacitors have been reviewed, which inspires potential strategies to develop high energy density graphene-based supercapacitors.
Congratulations Shao Ing!
Kit-Ying's paper, Multifunctional graphene oxide paper embodied structural dielectric capacitor based on carbon fibre reinforced composites, has been accepted by the Journal of Composites Science and Technology [Link]. Han and Baohua are listed as co-authors.
In this study, the multifunctionality of structural dielectric capacitor made by integrating graphene oxide paper into carbon fibre reinforced composite has been investigated. It is revealed that both electrical and mechanical properties of the structural dielectric capacitors were significantly enhanced by interleaving a graphene oxide paper in the middle of composite, indicating the excellent potential of graphene oxide paper in the development of multifunctional materials for energy storage, potentially for high strength required applications, such as electric vehicles and unmanned aerial vehicles.
Dr. Xuewen Wang received commendation for FSET (Faculty of Science, Engineering and Technology) ECR (Early Career Researcher) Award.
Dr. Han Lin and Professor Baohua Jia have won FSET Translation Award. It has been a severe competition with more than 80 applications for each award. Only by having those significant talents in LNI group, we are able to secure the prestigious awards!
LNI group celebrated Xiaorui's PhD graduation at Colorful Yunan. Congratulations Xiaorui!