Hin-Lap Yip

Hin-Lap Yip
City University of Hong Kong | CityU · Department of Materials Science and Engineering & School of Energy and Environment

Professor

About

316
Publications
116,251
Reads
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31,183
Citations
Citations since 2016
184 Research Items
23209 Citations
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201620172018201920202021202201,0002,0003,0004,000
201620172018201920202021202201,0002,0003,0004,000
Additional affiliations
December 2020 - December 2020
City University of Hong Kong
Position
  • Professor
Description
  • Prof. Yip’s research is in the general area of solution processed optoelectronic materials and devices for energy generation and energy saving. His research focuses on understanding the structure-property relationships, device physics and photophysics, and device optimization of 1) organic solar cells, 2) perovskite solar cells and 3) perovskite LEDs.
June 2013 - December 2020
South China University of Technology
Position
  • Professor
January 2009 - May 2013
University of Washington Seattle
Position
  • PostDoc Position

Publications

Publications (316)
Article
Metal oxides are commonly employed as electron transport layers (ETLs) for n-i-p perovskite solar cells (PSCs), but the presence of surface traps and their mismatched energy alignment with perovskites limits the corresponding device performance. Therefore, the interfacial modification of ETLs by functional molecules becomes an important strategy fo...
Article
Polymeric hole-transport materials (HTMs) play a critical role in determining the device performance and stability of perovskite solar cells (PVSCs). Fluorination on the conjugated backbone has been found to have the potential to modulate the molecular planarity, electrical property, and photovoltaic performance of the resulting polymer materials....
Article
High specific power or power to mass ratio is a critical concern of photovoltaic (PV) for aerospace applications. Organic solar cells (OSCs) have advantages such as high absorption coefficient, compatibility with flexible substrate, light- weight, etc. Moreover, recently OSCs achieved power conversion efficiency (PCE) over 20% with the incorporatio...
Article
Visible and near-infrared (NIR) light dual-band photodetectors (PDs) have potential applications in signal detection, bioimaging, optical communications and safety monitoring. Herein, we report an ultrafast perovskite/organic heterojunction dual-mode PD with a voltage-modulated photoresponse range in visible and NIR spectra. The PD, comprising a pe...
Article
Organic photovoltaics (OPVs) have progressed steadily through three stages of photoactive materials development: (i) use of poly(3-hexylthiophene) and fullerene-based acceptors (FAs) for optimizing bulk heterojunctions; (ii) development of new donors to better match with FAs; (iii) development of non-fullerene acceptors (NFAs). The development and...
Article
Full-text available
Although the performance of blue perovskite LEDs (PeLEDs) has improved rapidly in the past few years, it still lags behind their green and red counterparts. One major cause of the inferior performance is the relatively low photoluminescence quantum yield (PLQY) of blue perovskite emitters due to more severe nonradiative recombination loss induced b...
Article
Quasi‐2D perovskites show great promise for light‐emitting diodes owing to suppressed non‐radiative losses enabled by the energy funneling/cascading nanostructures. However, for red emission quasi‐2D perovskites, these ideal energy landscapes for efficient perovskite light‐emitting diodes (PeLEDs) can rarely be achieved due to detrimental aggregati...
Article
Full-text available
Colloidal lead-halide perovskite nanocrystals (LHP NCs) have emerged over the past decade as leading candidates for efficient next-generation optoelectronic devices, but their properties and performance critically depend on how they are purified. While antisolvents are widely used for purification, a detailed understanding of how the polarity of th...
Article
Full-text available
Hybrid devices based on a heterojunction between inorganic and organic semiconductors have offered a means to combine the advantages of both classes of materials in optoelectronic devices, but, in practice, the performance of such devices has often been disappointing. Here, it is demonstrated that charge generation in hybrid inorganic-organic heter...
Article
Full-text available
Tandem structures with different subpixels are promising for perovskite‐based multicolor electroluminescence (EL) devices in ultra‐high‐resolution full‐color displays; however, realizing excellent luminance‐ and color‐independent tunability considering the low brightness and stability of blue perovskite light‐emitting diodes (PeLEDs) remains a chal...
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Full-text available
Non-fullerene acceptors (NFAs) are excellent light harvesters, yet the origin of their high optical extinction is not well understood. In this work, we investigate the absorption strength of NFAs by building a database of time-dependent density functional theory (TDDFT) calculations of ∼500 π-conjugated molecules. The calculations are first validat...
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Full-text available
Solution processable quasi-2D (Q-2D) perovskite materials are emerging as a promising candidate for blue light source in full-color display applications due to their good color saturation property, high brightness, and spectral tunability. Herein, an efficient energy cascade channel is developed by introducing sodium bromide (NaBr) in phenyl-butyla...
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Full-text available
Monolithic perovskite/organic tandem solar cells have attracted increasing attention due to their potential of being highly efficient while compatible to facile solution fabrication processes. One of the limiting factors for improving the performance of perovskite/organic tandem cells is the lack of wide‐bandgap perovskites with suitable bandgap, f...
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Full-text available
See-through power windows are developed herein via a new design of semitransparent organic solar cells (ST-OSCs) that allows for the efficient utilization of spectrum-engineered solar photons from the visible to infrared range with both energy generation and saving features. These OSC-derived power windows simultaneously possess high color fidelity...
Article
Polymer hole‐transport layers (HTLs) are critical components of inverted perovskite solar cells (IPVSCs). Triphenylamine derivatives PTAA (poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine]) and Poly‐TPD (poly[N,N′‐bis(4‐butylphenyl)‐N,N′‐bis(phenyl)benzidine]) have been widely adopted as hole‐transport materials due to their perovskite passivation ef...
Preprint
Full-text available
Non-fullerene acceptors (NFAs) are excellent light harvesters, yet the origin of such high optical extinction is not well understood. In this work, we investigate the absorption strength of NFAs by building a database of time-dependent density functional theory (TDDFT) calculations of ~500 pi-conjugated molecules. The calculations are first validat...
Article
As one of the core parts of two-terminal (2T) monolithic tandem photovoltaics, the interconnecting layers (ICLs) play a critical role in modulating the carrier transport and recombination between the sub-cells, and thus influencing the tandem device performance. Here, for the first time, the relationship between ICLs architecture and 2T monolithic...
Article
Organic solar cells (OSCs) suffer from severe upscaling loss due to the inevitable formation of inhomogeneities and the intrinsically low charge mobilities of organic materials limiting the charge extraction efficiency, especially in the situation where cell width reaches centimeter scale. Here, we report the introduction of a nematic liquid crysta...
Article
Fair and meaningful device performance comparison among luminescent solar concentrator-photovoltaic (LSC-PV) reports cannot be realized without a general consensus on reporting standards in LSC-PV research. Therefore, it is imperative to adopt standardized characterization protocols for these emerging types of PV devices that are consistent with ot...
Article
2D/3D Perovskites In article number 2102973, Qifan Xue, Hong Li, Jean-Luc Brédas, Hin-Lap Yip and co-workers report a spacer tailoring strategy to regulate the interfacial properties of diammonium-based 2D/3D perovskite heterostructures, which allows the well-controlled phase composition and crystalline orientation and enhanced surface passivation...
Article
The rational synthesis of thiophene-based cross-coupled polymers on surfaces has been attracting more attention recently. Here, we report the stepwise activation of 5,5'-(2,3-difluoro-1,4-phenylene)bis(2-bromothiophene) as a precursor to synthesize thiophene-based polymeric ribbons on the Au(111) surface. Scanning tunneling microscopy studies showe...
Article
Full-text available
The band‐edge electronic structure of lead halide perovskites (ABX3) is composed of the orbitals of B and X components and can be tuned through the composition and structure of the BX6 octahedron. Although A‐site cations do not directly contribute to near‐edge states, the bandgap of 3D metal halide perovskites can be affected by A‐cations through B...
Article
As a revolutionary semiconductor, metal halide perovskite-based optoelectronic devices have enabled competitive device performance compared with that of commercialized rivals, including solar cells (SCs), light-emitting diodes (LEDs), and photodetectors (PDs). Despite the high performance of perovskite-based optoelectronic devices, there remain sev...
Article
Full-text available
Transient optical spectroscopy is used to quantify the temperature-dependence of charge separation and recombination dynamics in P3TEA:SF-PDI2 and PM6:Y6, two non-fullerene organic photovoltaic (OPV) systems with a negligible driving force and high photocurrent quantum yields. By tracking the intensity of the transient electroabsorption response th...
Article
Full-text available
Following the 1st release of the “Emerging photovoltaic (PV) reports”, the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer-reviewed articles in academic journals since August 2020. Updated graphs, tables, and analyses are provided with sever...
Article
Full-text available
Recent studies of sky-blue perovskite light-emitting diodes (PeLEDs) have extensively promoted optimal device design to achieve an external quantum efficiency (EQE) above 12%. However, the development of thin-film deep-blue PeLEDs lags dramatically behind, especially with regards to meeting the latest Rec. 2020 standard. A trichloro(3,3,3-trifluoro...
Article
Full-text available
Perovskite solar cells (PVSCs) have drawn great attention due to their excellent photovoltaic performance. Recently, all-inorganic PVSCs have been extensively studied owing to their superior thermal and photo stability. Among them, CsPbIBr2 perovskite stands out due to its superb phase stability in ambient environment. However, the severe energy lo...
Article
Full-text available
Perovskite solar cells (PSCs) based on 2D/3D heterostructures show great potential to combine the advantages of the high efficiency of 3D perovskites and the high stability of 2D perovskites. However, an in‐depth understanding of the organic‐spacer effects on the 2D quantum well (QW) structures and electronic properties at the 2D/3D interfaces is y...
Article
Full-text available
Quasi‐2D perovskites have long been considered to have favorable “energy funnel/cascade” structures and excellent optical properties compared with their 3D counterparts. However, most quasi‐2D perovskite light‐emitting diodes (PeLEDs) exhibit high external quantum efficiency (EQE) but unsatisfactory operating stability due to Auger recombination in...
Preprint
Following the 1 release of the “Emerging PV reports” , the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer-reviewed articles in academic journals since August 2020. Updated graphs, tables and analyses are provided with several performance pa...
Preprint
Following the 1 release of the “Emerging PV reports” , the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer-reviewed articles in academic journals since August 2020. Updated graphs, tables and analyses are provided with several performance pa...
Article
Metal halide perovskites are considered as a game-changer for future solar cell technology due to their rapidly increased device efficiencies and potential for manufacturing at low cost. In view of their promising commercial potential, increasing research efforts have now been dedicated to the development of large-area perovskite solar modules. In...
Article
Full-text available
The maximum photocurrent in tandem organic solar cells (TOSCs) is often obtained by increasing the thicknesses of sub‐cells, which leads to recombination enhancement of such devices and compromises their power conversion efficiency (PCE). In this work, an efficient interconnecting layer (ICL) is developed, with the structure ZnO NPs:PEI/PEI/PEDOT:P...
Article
Full-text available
Benefiting from low cost and simple synthesis, polythiophene (PT) derivatives are one of the most popular donor materials for organic solar cells (OSCs). However, polythiophene‐based OSCs still suffer from inferior power conversion efficiency (PCE) than those based on donor–acceptor (D–A)‐type conjugated polymers. Herein, a fluorinated polythiophen...
Article
Recent advances in organic solar cells (OSCs) based on large-bandgap donors and low-bandgap non-fullerene acceptors (NFAs) have increased the power conversion efficiency (PCE) of OSCs to ∼18%. However, these state-of-the-art OSCs have strong absorption in the visible region, limiting their application in semitransparent organic solar cells (STOSCs)...
Article
Organic solar cells (OSCs) show great promise for future applications due to their merits of low cost, flexibility, aesthetic beauty with vivid colors, etc. However, the “conventional” device architecture with brittle and expensive glass/indium tin oxide (ITO) transparent electrode weakens these potential advantages, and restricts it to small area...
Article
Full-text available
Metal‐halide perovskites (MHPs) are regarded as ideal photovoltaic materials because of their variable crystal material composition and superb optoelectronic performance. However, this compositional variability results in a complicated crystallization process during MHP film fabrication, leading to reduced MHP film crystallinity and decreased perfo...
Article
Despite the rapid development of CsPbIxBr3−x (0 ≤ x ≤ 3) inorganic perovskite solar cells, associated with their superior thermal stability, their low moisture stability limits their commercial deployment. In this study, 1D‐2D‐3D multidimensional coupled perovskites are prepared by means of an in situ self‐integration approach. This pioneering meth...
Article
Full-text available
Low-dimensional metal halide perovskites have emerged as promising alternatives to the traditional three-dimensional (3D) components, due to their greater structural tunability and environmental stability. Dion-Jacobson (DJ) phase two-dimensional (2D) perovskites, which are formed by incorporating bulky organic diammonium cations into inorganic fra...
Article
Here we provide a comprehensive review of a newly developed lighting technology based on metal halide perovskites (i.e. perovskite light-emitting diodes) encompassing the research endeavours into materials, photophysics and device engineering. At the outset we survey the basic perovskite structures and their various dimensions (namely three-, two-...
Preprint
Emerging photovoltaics (PVs), focuses on a variety of applications complementing large scale electricity generation. For instance, organic, dye-sensitized and some perovskite solar cells are considered in building integration, greenhouses, wearable and indoors, thereby motivating research on flexible, transparent, semitransparent, and multi-junctio...
Article
Metal halide perovskite materials occupy an increasingly important position in the field of optoelectronic materials due to their excellent light absorption properties, long carrier dispersion length and high mobility. However, the instability of perovskite materials is still a major factor constraining its development. So, its' important to improv...
Article
Semi‐transparent organic photovoltaics (ST‐OPVs) are promising solar windows for building integration. Improving the light‐absorbing selectivity, that is, transmitting the visible photons while absorbing the invisible ones, is a key step toward high‐performance ST‐OPV. To achieve this goal, the optical properties of the active layer, transparent el...
Article
As an effective molecular modification strategy, side chain engineering has been widely used in promoting the photovoltaic performance of non-fullerene acceptors. Herein, a novel non-fullerene small molecular acceptor i-IEOSi-4F comprising siloxane-terminated alkoxyl side chain was successfully designed and synthesized. The molecule shows an optica...
Article
Full-text available
Monolithic perovskite solar cells (PSCs) and small‐bandgap organic photovoltaics (OPVs) integrated perovskite/organic tandem devices and binary perovskite/bulk‐heterojunction (BHJ) devices have recently attracted tremendous attention due to their upgraded light‐harvesting range and theoretical efficiency potential. However, compared with the ideal...
Preprint
Emerging photovoltaics (PVs), focuses on a variety of applications complementing large scale electricity generation. For instance, organic, dye-sensitized and some perovskite solar cells are considered in building integration, greenhouses, wearable and indoors, thereby motivating research on flexible, transparent, semitransparent, and multi-junctio...
Article
The development of low-cost and efficient hole transport materials (HTMs) is important for the commercialization of perovskite solar cells (PSCs). Comparing with the widely studied D-A-D and D-π-D linear-type small molecule HTMs, DTB-FL with a D-A-π-A-D molecular design is proposed, featuring facile synthesis and excellent optoelectronic properties...
Article
The inferior light extraction efficiency (LEE), which is generally less than 20%, based on optical modeling, and the difficulty in achieving white emission are the two main challenges in the metal-halide-perovskite light-emitting diode (PeLED) field. Herein, we report a simple and efficient approach to construct high-performance white PeLEDs with m...
Article
Despite demonstrating higher photoluminescence quantum yield and better ambient and operational stability than organic-inorganic hybrid perovskites, all-inorganic perovskites encounter the problem of inferior film quality and interfacial electrical properties, which...
Article
Planar heterojunction (PHJ) organic photodetectors are potentially more stable than traditional bulk heterojunction counterparts because of the absence of uncontrolled phase separation in the donor and acceptor binary blend system. This work reports a new class of PHJ organic photodetectors based on the medium-band gap fullerene C60 and low-band ga...
Article
Full-text available
Emerging photovoltaics (PVs) focus on a variety of applications complementing large scale electricity generation. Organic, dye‐sensitized, and some perovskite solar cells are considered in building integration, greenhouses, wearable, and indoor applications, thereby motivating research on flexible, transparent, semitransparent, and multi‐junction P...
Article
Full-text available
Organic solar cells based on non-fullerene acceptors can show high charge generation yields despite near-zero donor–acceptor energy offsets to drive charge separation and overcome the mutual Coulomb attraction between electron and hole. Here, we use time-resolved optical spectroscopy to show that free charges in these systems are generated by therm...