Chwenhaw Liao

• Doctor of Philosophy
• The University of Sydney

The successful development of optoelectronic devices is contingent on a detailed understanding of interactions between light and excited energy states in photoactive materials. In 2D perovskites, excitons are the dominant photogenerated species and their energetic structure plays a pivotal role, governing photon absorption and emission processes. I...

Perovskite whentandemed with organic photovoltaics (OPV) for double‐junctions have efficiencypotentials over 40%. However, there is still room for improvement suchas better current matching, higher fill factor, as well as lower voltage and fill factor losses in the top perovskite cell. Here weaddress the issue associated with the top perovskite cel...

Metal halide perovskite solar cells have achieved tremendous progress and have attracted enormous research and development efforts since the first report of demonstration in 2009. Due to fabrication versatility, many heat treatment methods can be utilized to achieve perovskite film crystallization. Herein, 10.6 µm carbon dioxide laser process is su...

C60 is a widely used electron selective material for p–i–n perovskite cells, however, its energy level does not match well with that of a wide‐bandgap perovskite, resulting in low open‐circuit voltage (VOC) and fill factor (FF). To overcome this issue, ultra‐thin LiF has been widely used as an interlayer between C60 and perovskite layers facilitati...

Two-dimensional (2D) organic–inorganic metal halide perovskites have gained immense attention as alternatives to three-dimensional (3D) perovskites in recent years. The hydrophobic spacers in the layered structure of 2D perovskites make them more moisture-resistant than 3D perovskites. Moreover, they exhibit unique anisotropic electrical transport...

While many state-of-the-art perovskite solar cells (PSCs) have been realized on rigid glass substrates, demonstrating perovskite cells on other types of surfaces may give rise to new applications. Here, we successfully demonstrate efficient PSCs on steel. The role of an indium tin oxide interlayer as a barrier against iron diffusion from the steel...

The drastic reduction in launch and manufacturing costs of space hardware has facilitated the emergence of "commercial" space. Radiation‐hard organometal halide perovskite solar cells (PSCs) with low‐cost and high‐efficiency potentials are promising for space applications.High‐efficiency PSCs are tested with different hole transport materials (HTMs...

Detection of ionizing radiation is one of the foundations of modern society, with critical technological applications in medical diagnostics and treatment, space exploration, the nuclear energy industry, and border security. However, the rapidly increasing use of radiation in recent decades has correlated to higher radiation exposure in the populat...

Two‐dimensional (2D) tin (Sn)‐based perovskites have recently received increasing research attention for perovskite transistor application. Although some progress is made, Sn‐based perovskites have long suffered from easy oxidation from Sn²⁺ to Sn⁴⁺, leading to undesirable p‐doping and instability. In this study, it is demonstrated that surface pas...

Metal halide perovskite materials demonstrate immense potential for photovoltaic and electronic applications. In particular, two-dimensional (2D) layered metal halide perovskites have advantages over their 3D counterparts in optoelectronic applications due to their outstanding stability, structural flexibility with a tunable bandgap, and electronic...

Tandem solar cells promise to overcome the theoretical single junction solar cell efficiency limit. Here we report an elegant approach to monolithically integrate perovskite and Si-heterojunction tandem solar cell by...

Solar‐Driven Hydrogen Production In article number 2204807, W. Y. Ho‐Baillie, Hongjun Chen, and co‐workers report a solar‐driven hydrogen production with a 98.6% faradaic efficiency and 33% power savings compared to conventional water‐splitting without the use of ion‐selective membranes. The process produces a high‐value by‐product, a conductive po...

To reduce the reliance on fossil fuel, H2, as a clean fuel, has attracted substantial research and development activities in recent years. The traditional water splitting approach requires an applied bias of more than 1.5 V and the use of ion‐selective membranes to prevent the formation of a potentially explosive H2–O2 gas mixture, resulting in inc...

Fabricating perovskite solar cells (PSCs) in air is conducive to low‐cost commercial production, nevertheless it is rather difficult to achieve comparable device performance as that in an inert atmosphere because of poor moisture toleration of perovskite materials. Here, the perovskite crystallization process was systematically studied using two‐st...

High bandgap perovskite solar cells are integral to perovskite‐based multi‐junction tandem solar cells with efficiency potentials over 40%. However, at present, high bandgap perovskite devices underperform compared to their mid bandgap counterparts in terms of voltage outputs and fill factors resulting in lower than ideal efficiencies. Here, the lo...

2D Perovskites Cs2Pb(SCN)2Br2, an inorganic‐cation pseudo‐halide 2D phase perovskite single crystal, is grown by a simple antisolvent vapor‐assisted crystallization method, as reported by Chu‐Chen Chueh, Anita W. Y. Ho‐Baillie, and co‐workers in article number 2104782. Cs2Pb(SCN)2Br2 exhibits a reversible first‐order phase transformation to CsPbBr2...

Various layered lead halide perovskites based on the Ruddlesden–Popper (RP) structure with the general formula of An+1BnX3n+1 (n = 1, 2, …) have been developed. Most of them are comprised of alternating layered perovskite-like stacks and an organic spacer with a long insulating chain especially for the A-site-substituted RP-type perovskites. To dat...

Large magnetic optical rotary dispersion (Faraday rotation) has been demonstrated recently in methylammonium lead bromide. Here, we investigate the prospect of extending the active spectral range by altering the halogen. We also investigate the origins of large Faraday rotation in these diamagnetic materials using magnetic circular dichroism (MCD)...

Reaction of the metalloligand IrIII(ppy-COOH)3 and the anisotropic paramagnetic CoII ion under solvothermal conditions resulted in a metal-metalloligand coordination polymer, [CoII3(μ3-O)(μ-OH2){IrIII(ppy-COO)2(ppy-COOH)}2(H2O)4]·2DMF·xH2O (I). It consists of trimeric Co3O secondary building units (SBUs) bridged by pairs of Ir to form chains of alt...

Lead halide perovskites (LHPs) have become a promising alternative for a wide range of optoelectronic devices, thanks to their solution‐processability and impressive optical and electrical properties. More recently, LHPs have been investigated in magneto‐optic studies and have exhibited spin‐polarized emission, photoinduced magnetization, and long...

Improving the quality of perovskite poly‐crystalline film is essential for the performance of associated solar cells approaching their theoretical limit efficiency. Pinholes, unwanted defects, and nonperovskite phase can be easily generated during film formation, hampering device performance and stability. Here, a simple method is introduced to pre...

Downshifting antireflection film for an efficient and UV-stable monolithic perovskite/silicon tandem solar cell is presented.

Bimetallic MOF precursors can produce homogeneous distribution of mixed-metal oxides after calcination, thus may provide high efficiency as electrocatalyst in the water splitting process. We designed a layered bimetallic-organophosphonate containing Ir, Co and P because the metal-oxides are well-known for their efficiency in oxygen-evolution reacti...

UV induced degradation and parasitic ultraviolet (UV) absorption by the “sun-facing” carrier transport layer in a perovskite cell hinders stability and electrical performance when the perovskite cell is a top cell for a Si-based tandem. In this work, we tackle these issues by applying textured polydimethylsiloxane (PDMS) films that incorporate a do...

Inorganic lead halide perovskites have attracted attention due to their tolerance to higher processing temperature and higher bandgap suitable for tandem solar cell application. Not only do they improve cell stability and efficiency, they also reveal many interesting and un‐anticipated material qualities. This work reports a simple cation exchange...

Three iridium(III)-based metal-organic frameworks (MOFs), namely [Cd3{Ir(ppy-COO)3}2(DMF)2(H2O)4]·6H2O·2DMF (1), [Cd3{Ir(ppy-COO)3}2(DMA)2(H2O)2]·0.5H2O·2DMA (2), and [Cd3{Ir(ppy-COO)3}2(DEF)2(H2O)2]·8H2O·2DEF (3) (ppy-COOH = methyl-3-(pyridin-2-yl)benzoic acid, DMF = N,N-dimethylformamide, DMA = N,N-dimethylacetamide, DEF = N,N-diethylformamide),...

Artificial control and engineering of metal-organic framework crystals with defects can endow them with suitable properties for application in gas storage, separation and catalysis. In this work, we synthesized a series of defective Ir-containing metal organic frameworks [Zn4(µ4-O)(Ir-A)2(1-x)(Ir-B)2x] (ZnIr-MOF-dx) by doping heterostructural linke...