Koko Kwok-Ho Lam

• Ph.D.
• Professor (Associate) at The Hong Kong Polytechnic University

Group IVA elements have aroused attention in sodium-ion batteries (SIBs) due to their Na-storage capability. Among them, Pb is less explored perhaps due to its perceived risks, but its long-standing success in Pb-acid batteries should not be neglected. Together with the well-established recycling procedures, the merits of Pb warrant further investi...

Invited for this issue's Front Cover is the group from K. H. (Koko) Lam (The Hong Kong Polytechnic University, University of Glasgow). The front cover picture illustrates 3D interconnected nanoporous electrodes featuring a nano‐cage structure, wrapping active materials within. This distinctive electrode design enhances contact between active materi...

Optical-resolution photoacoustic endoscopy (OR-PAE) has been proven to realize imaging on the vascular network in the gastrointestinal (GI) tract with high sensitivity and spatial resolution, providing morphological information. Various photoacoustic endoscopic catheters were developed to improve the resolution and adaptivity of in-vivo imaging. Ho...

The pursuit of supercapacitors with simultaneous high power and energy densities has led to extensive research and successful outcomes through the integration of three‐dimensional (3D) electrodes, encompassing both 3D active materials and 3D porous current collectors. This mini review provides a summary of recent developments in supercapacitors fea...

Piezoelectric 1-3 composite materials have become extensively utilized in diagnostic ultrasound transducers owing to their high electromechanical coupling coefficient, low acoustic impedance, and low dielectric loss. In this study, Sm-doped PMN-PT ceramic/epoxy 1-3 composite with a ceramic volume fraction of 60% is fabricated by the dice-and-fill m...

Ammonium vanadates, featuring an N─H···O hydrogen bond network structure between NH4⁺ and V─O layers, have become popular cathode materials for aqueous zinc‐ion batteries (AZIBs). Their appeal lies in their multi‐electron transfer, high specific capacity, and facile synthesis. However, a major drawback arises as Zn²⁺ ions tend to form bonds with el...

Group IVA elements exhibit some interesting sodium capabilities via electrochemical alloying processes (except carbon). Among them, tin is believed to be the most promising anode candidate for sodium-ion batteries (SIBs) due to its simple fabrication and monolithic form (e.g., metallic foils).[1] Nevertheless, tin foil anodes usually fail premature...

The fabrication method plays a key role in the performance of lead magnesium niobate–lead titanate-based ceramics. (1 − w)[Pb(Mg1/3Nb2/3)0.67Ti0.33O3]-w[Pb1−1.5xSmx(Mg1/3Nb2/3)yTi1−yO3] piezoelectric ceramics were prepared by sintering the mixture of two different crystalline phases in which two pre-sintered precursor powders were mixed and co-fire...

Group IVA elements exhibit interesting Na storage capabilities due to the success of their Li alloy analogues. However, beyond hard carbon, they remain poorly understood as anodes for sodium-ion batteries (SIBs). Here, kinetic investigations of the electrochemical sodiation of Si and Ge are conducted using liquid electrolytes and half-cell configur...

Aqueous zinc‐ion batteries (AZIBs) have attracted considerable attention due to their low cost and environmental friendliness. However, the rampant dendrite growth and severe side reactions during plating/stripping on the surface of zinc (Zn) anode hinder the practicability of AZIBs. Herein, an effective and non‐toxic cationic electrolyte additive...

Sodium superionic conductor (NASICON)‐type Na3V2(PO4)3 has attracted considerable interest owing to its stable three‐dimensional framework and high operating voltage; however, it suffers from a low‐energy density due to the poor intrinsic electronic conductivity and limited redox couples. Herein, the partial substitution of Mn³⁺ for V³⁺ in Na3V2(PO...

Photoacoustic imaging (PAI) uniquely combines optics and ultrasound, presenting a promising role in biomedical imaging as a non-invasive and label-free imaging technology. As the traditional opaque ultrasound (US) transducers could hinder the transportation of the excitation light and limit the performance of PAI system, piezoelectric transparent u...

Aqueous flexible supercapacitors have promising potential in the application of wearable electronics but are limited by their low energy densities. Typically, thin nanostructured active materials are deposited on current collectors to achieve high specific capacitances based on active materials, yet the capacitance of total electrodes is sacrificed...

With the rapid development of micro‐energy harvesting technology, noise has great potential as a new type of micro‐energy source by developing a high‐performance acoustic energy harvester (AEH). Nevertheless, the challenges of harvesting energy from noise are low acoustic energy density, multi‐frequency mixed sound, and unstable sound pressure. Pie...

Photoacoustic technology is a promising tool to provide morphological and functional information in biomedical research. To enhance the imaging efficiency, the reported photoacoustic probes have been designed coaxially involving complicated optical/acoustic prisms to bypass the opaque piezoelectric layer of ultrasound transducers, but this has led...

The effect of polydopamine (PDA) modification on aminated Fe3O4 nanoparticles (Fe3O4-NH2)/graphite oxide (GO)/β-cyclodextrin polymer cross-linked by citric acid (CDP-CA) composites were studied for the removal of a cationic dye (methylene blue, MB) and an anionic dye (Congo red, CR) from waters. The micro-structural and magnetic characterizations c...

Photoacoustic technology is a promising tool to provide morphological and functional information in biomedical research. To enhance the imaging efficiency, the reported photoacoustic probes have been designed coaxially involving complicated optical/acoustic prisms to bypass the opaque piezoelectric layer of ultrasound transducers, but leading to bu...

A two-step modification for the electrochemical performance of Si-based anodes for LIBs is achieved in this study. Firstly, the Cr element is chosen as the doped media into Si bulk via a HEBM method and the fabricated Si-Cr precursors consist of nanocrystalline Si, CrSi2, and amorphous Si. The electrochemical analysis reveals that all ball-milled s...

The development of advanced electrode materials with fast reaction kinetics and optimized morphology is key to achieving high-performance hybrid supercapacitors with high energy density and outstanding cycling performance. Herein, an ingenious strategy is developed to prepare M doped Ni2P/Co2P (M = Cu, Zn, Mo) bimetallic phosphide electrode materia...

Recently, potassium-ion batteries (PIBs) have been considered as one of the most promising energy storage systems; however, the slow kinetics and large volume variation induced by the large radius of potassium ions (K+) during chemical reactions lead to inferior structural stability and weak electrochemical activity for most potassium storage anode...

The fast capacity degradation of silicon‐based anodes significantly limits the application in lithium‐ion battery (LIB) industries. Recently, Si−CuO composites have been reported as promising anodes in terms of being cost‐effective and technically feasible, but improved cycle stability is still desired. This work introduces a proper amount of NiO i...

Cu2SnS3 (CSS) has gained great attraction due to its constitutive earth-abundant elements and intrinsic low lattice thermal conductivity, κl, potentially providing high quality factor, B, and high zT value. However, the lack of band convergence is the bottleneck to enhancing the thermoelectric performance of Cu2SnS3 when performing the band enginee...

With the advent of lithium-ion batteries (LIBs) and electric vehicle (EV) technology, the research on the battery State-of-Charge (SoC) estimation has begun to rise and develop rapidly. In order to objectively understand the current research status and development trends in the field of battery SoC estimation, this work uses an advanced search meth...

With the popularization of humans working in tandem with robots and artificial intelligence (AI) by Industry 5.0, ultrasonic non-destructive testing (NDT)) technology has been increasingly used in quality inspections in the industry. As a crucial part of handling ultrasonic testing results–signal processing, the current approach focuses on professi...

Synthesis of three-dimensional (3D) porous current collectors is a pioneering strategy to improve the energy density and power density of wire-like supercapacitors. The strategy is further promoted in this work...

Ultrasonic signal analysis is an essential technique used in various fields, including non-destructive testing (NDT), structural health monitoring, and medical diagnosis. Accurate auto-diagnosis of Time-of-Flight ( ToF ) for ultrasonic signal is crucial in defects locating, ultrasound imaging, etc. However, requisite signal extraction for ToF estim...

Recent research pointed out that the degree of inflammation in the adventitia could correlate with the severity of atherosclerotic plaques. Intravascular photoacoustic endoscopy can provide the information of arterial morphology and plaque composition, and even detecting the inflammation. However, most reported work used a non‐coaxial configuration...

With the popularization of electric vehicles (EVs), the voltage and state-of-charge (SOC) estimations of rechargeable batteries are of great significance. The SOC parameter has been used as an indicator for delivering the electrical energy of rechargeable lithium-ion batteries (LIBs), while the voltage has been a critical parameter needed to monito...

A fluorine-free strategy was developed for the hydrophobic modification of the melamine (MA) sponge, in which both the stearic acid-modified Fe3O4 nanoparticles (SA-Fe3O4) and the graphite oxide were immobilized on the MA sponge with the use of 3-aminopropyltriethoxysilane by a drop-coating method to prepare the SA-Fe3O4/GO/MA sponge for oil-water...

The huge volume change of Si anode with fast capacity degradation limits its commercialization in LIBs. The co-introduction of metal and O elements into the Si bulk fabricating Si-metal silicide-Si oxides composites has been proven an effective way to overcome this issue. Among them, Si-CuO composites, due to financial feasibility and environmental...

In this work, the multi-walled carbon nanotubes (MWCNTs)/poly(vinylidene fluoride) (PVDF) composites were prepared by the electrospinning-hot pressing method. The MWCNTs distributed well in the PVDF matrix, which was confirmed by the investigation of scanning electron microscope. According to the results of the Fourier transform infrared and the wi...

NiO was introduced into Si-CuO alloys as anode materials in LIBs by an affordable manufacturing high-energy ball-milling method the first time. The study found the ball-milled Si-CuO-NiO composites could effectively suppress the formation of the Li3.75Si phase during the lithiation process. With increasing the proportion of NiO, there was obvious i...

Silicon (Si) is a promising anode material for Li-ion batteries but its application is limited due to its severe volume change during the lithiation/delithiation process, leading to a fast degradation of cycle performance. Applying transition metals to dope into the bulk Si forming active/inactive silicide phase is proved as an effective and practi...

In vivo ultrasound imaging with phased array transducers is of great importance for both clinical application and biomedical research. In this work, relaxor ferroelectric PMN-0.28PT single crystal with very high piezoelectric constant d33 ≥ 2000 pC/N and electromechanical coupling coefficient k33 ∼ 0.92 is used to fabricate high-frequency phased ar...

Silicon (Si) is a promising anode material for Li-ion batteries but its application is limited due to its severe volume change during the lithiation/delithiation process leading to a fast degradation of cycle performance. Applying transition metals to dope into the bulk of Si forming active/inactive silicide phase is proved an effective and practic...

Light and flexible thermoelectric generators working around room temperature and within a small temperature range are much desirable for numerous applications of wearable microelectronics, internet of things, and waste heat recovery. Herein, we report a high performance flexible thermoelectric generator made of polymeric thermoelectric composites a...

Rechargeable aqueous Zn-ion batteries (ZIBs) are deemed as powerful candidates for large-scale energy-storage systems because of their intrinsic safety, inexpensive cost, and environment friendliness. However, the performance degeneration of ZIBs occurs by virtue of structural instability and uncompetitive conductivity of cathode materials. In this...

Silicon (Si) is a promising anode material for Li-ion batteries but its application is limited due to its low electronic conductivity and severe volume change during the lithiation/delithiation process. Recently, coating a carbon layer on the Si surface and doping the alloy phase into the bulk Si have been considered as effective approaches to reso...

NASICON-structured materials with high ionic conductivity, robust structure, and high operation potential have aroused extensive attentions as cathode for sodium-ion batteries (SIBs). However, the poor intrinsic electronic conductivity and low specific capacity are crucial obstacles for practical application of NASICON materials. Herein, a new NASI...

It is an inevitable choice to find efficient and economically-friendly electrocatalysts to reduce the high overpotential of oxygen evolution reaction (OER), which is the key to improve the energy conversion efficiency of water splitting. Herein, we synthesized Cu2S/Ni3S2 catalysts on nickel foam (NF) with different molar ratios of Ni/Cu by a simple...

Large-sized multiferroics Pb(Fe1/2Nb1/2)O3 (PFN) single crystal was grown by Bridgeman method in order to understand the giant dielectric response by investigating the electrical conductivity and dielectric properties. The synchrotron radiation soft x-ray absorption spectrum revealed the valence states of Fe in PFN crystal. PFN exhibits semiconduct...

(1- w )[Pb(Mg 1/3 Nb 2/3 ) 0.67 Ti 0.33 O 3 ]- w [Pb 1 − 1.5 x Sm x (Mg 1/3 Nb 2/3 ) y Ti 1− y O 3 ] ((1- w )PMN- w PSMN-PT) piezoelectric ceramics were prepared using the newly proposed twin-crystal mixed co-firing method in which two pre-sintered precursor powders were mixed and co-fired with designated ratios ( w = 0.3, 0.4, 0.5, 0.6). X-ray dif...

Aqueous rechargeable batteries have promising application in large-scale energy storage owing to their cost-effective, eco-friendly, high safety and good electrochemical performance. An aqueous rechargeable hybrid sodium/zinc battery with Zn anode, Na3MnTi(PO4)3 cathode and 0.5 mol L⁻¹ CH3COONa and Zn(CH3COO)2 mixed electrolyte has been designed fo...

Developing high-performing oxygen evolution reaction (OER) electrocatalysts under high-current operation conditions is critical for future commercial applications of alkaline water electrolysis for clean energy generation. Herein, we prepared a three-dimensional (3D) bimetallic oxyhydroxide hybrid grown on a Ni foam (NiFeOOH/NF) prepared by immersi...

Silicon oxide (SiOx) emerges as one of the most promising anodes for lithium-ion batteries (LIBs). However, the severe capacity fading arising from the structural degradation and low electronic conductivity still hinders its practical application. Herein, a novel SiOx anode material is constructed by embedding the SiOx microparticles into the 3D wr...

Tin sulfide (SnS2) is an excellent photocatalyst, which is widely used in reduction of heavy metal pollutants. However, its application is hindered by the rapid recombination of photogenerated carriers. In this study, a heterostructure composite composed of PANI, SnS2 and carbon sphere ([email protected]2@Cs) was prepared by a hydrothermal approach...

Myocardial infarctions are most often caused by the so-called vulnerable plaques, usually featured as non-obstructive lesions with a lipid-rich necrotic core, thin-cap fibroatheroma, and large plaque size. The identification and quantification of these characteristics are the keys to evaluate plaque vulnerability. However, single modality intravasc...

The manganese-based Prussian blue and its analogues (PBAs) are regarded as the promising cathode materials for sodium-ion batteries (SIBs). However, the effective suppression of Fe(CN)6 vacancies and removal of the absorbed and interstitial water in the crystal structure are two critical points to achieve the excellent electrochemical performance....

The sodium super ionic conductor (NASICON) materials are considered as the attractive cathode in sodium-ion batteries. Although the three-electron reactions in Na3MnTi(PO4)3 have greatly enhanced the capacity of NASICON-structure materials,...

Supercapacitor is characterized by its high power density, but the bottleneck is the limited mass loading and low specific capacitance of active materials in a single electrode. Although there have...

The successful synthesis of n-type nano PbS particles as sintering additives that highly promote densified PbTe 0.95 /PbS thermoelectric composites using the conventional sintering method, largely enhancing the zT value.

To improve the photocatalytic efficiency of the N2 reduction reaction, MXene quantum dots (Ti3C2-QDs) and two-dimensional (2D) nickel metal-organic framework (Ni-MOF) with different ratios were fabricated by a simple self-assembly strategy to form type II heterojunctions. The resultant composites showed enhanced absorption and excellent interfacial...

Intravascular photoacoustic (IVPA) imaging technology enables the visualization of pathological characteristics (such as inflammation activities, lipid deposition) of the artery wall. Blood flushing is a necessary step in improving the imaging quality in in vivo IVPA imaging. But the limited imaging speed of the systems stretches their flushing tim...

The degradation of interface and crystal structure during the cycle seriously hinders the further development and application of high-nickel cathode materials. In order to solve this problem, we synthesize a Al2O3 modified coating on LiNi0.88Co0.09Al0.03O2 (NCA) cathode material particles. However, further research discovers that the coating is not...

Lithium-sulfur (Li-S) battery has been considered as the next generation rechargeable battery due to the large specific capacity and high energy density. However, some technical problems still limit the commercialization value of LSBs such as poor electrical conductivity, shuttle effects and volume expansion. To overcome the aforementioned issues,...

The Na-doped layered Li1.2-xNaxMn0.534Ni0.133Co0.133O2 (x = 0, 0.05, 0.1 and 0.15) cathode materials with porous spherical structure for lithium-ion batteries have been successfully prepared via a facile co-precipitation method. The dual Li⁺/Na⁺ transport system is Li1.2-xNaxMn0.534Ni0.133Co0.133O2 cathode materials companying with dual Li⁺/Na⁺ ele...

Symmetric sodium ion batteries possess the promising features such as low cost, easy-manufacturing process, and facile recycling post-process, which are suitable for the application of large-scale stationary energy storage. Herein, we proposed a symmetric sodium ion battery based on dual-electron reactions of NASICON structured Na3MnTi(PO4)3 materi...

With the development of high-temperature thermoelectric materials, especially for the superionic copper selenide (Cu2-xSe), the thermal stability and cycling thermoelectric performance have become a great concern recently. Here we demonstrate that the excellent repeatability of the thermal cycling data of the simple Cu-Se binary system can be obtai...

Secondary electrocaloric effect (ECE) arising from piezoelectricity combined with crystal thermal expansion was often overlooked in ECE studies of ferroelectric ceramics. This work mainly evaluated the primary ECE (ΔTECE) and secondary ECE (∆T2) of eco-friendly BaSnxTi1-xO3 (BSnT100x, 0 < x < 12%) ceramics near the tetragonal (T)-orthorhombic (O) t...

Developing a thermoelectric generator(TEG) with shape conformable geometry for sustaining low-thermal impedance and large temperature gradient (ΔT) is fundamental for wearable and multi-scale energy harvesting applications. Here we demonstrate a flexible architectural design, with efficient thin film thermoelectric generator as a solution for this...

The presence of defects in thermoelectric materials plays a significant role in the modification their properties by influencing the behavior of electrons and phonons. Dopants with a unique f‐orbital can directly cause distortions in electronic density of states (eDOS) and phonon transport mechanism by intentionally inducing defects in their lattic...

Manganese dioxide (MnO2) with large theoretical capacity, low cost and rich reserves has been considered as one of the most promising advanced electrode materials of supercapacitors, but the shortage of electrochemical active sites and the inherent defects of electrical conductivity hinder its widespread application in high-performance supercapacit...

While lithium-ion batteries dominate the field of electronic devices and vehicles, recovery of LiCoO2 from spent batteries becomes a significant process. Aqueous lithium-air battery and dual-ion battery were blended into a novel electrochemical system as dual-ion lithium-air battery (DLAB) system to recover Li and Co elements from the spent LiCoO2...

Bimodal-grain structure (Ba 0.6 Sr 0.4 )TiO 3 ceramics had been prepared using induced abnormal grain growth method (IAGG). Two grain size distributions, between 10 ∼ 20 μm and 100 ∼ 300 μm, were found during the sintering temperature of 1250 ∼ 1350°C. Our results suggested that the ultra-large grain exhibited the high dielectric and ferroelectric...

It is challenging to achieve highly efficient thermoelectric materials due to the conflicts between thermopower (Seebeck coefficient) and electrical conductivity. These parameters are the core factors defining the thermoelectric property of any material. Here, we report the use of isovalent substitution as a tool to decouple the interdependency of...

Currently extensive attentions on recycling application from scrapped LiFePO4 power batteries of electric vehicles is attracted to the researchers. Owing to its stable olivine crystal structure and expensive preparation process relative to other cathode materials, the re-synthesis of LiFePO4 from spent batteries becomes an economical and convenient...

Electrochemical carbon dioxide (CO2) reduction (ECR) represents one of the most promising technologies for CO2 conversion into value-added feedstock from carbon monoxide (CO) to a variety of hydrocarbons. As the raw material for Fischer-Tropsch synthesis, CO is one of the most desirable ECR products and has recently received extensive research atte...

Defect engineering in thermoelectric materials leads to the formation of exotic transport properties. Specifically, reduction in lattice thermal conductivity (к L) can be realized through scattering of low and high-frequency pho-nons by interfacial and point defects respectively. Herein we explore such phenomena by inducing dense dislo-cations thro...

Invasiveness research is an essential step in breast cancer metastasis. The application of high-frequency ultrasound microbeam stimulation (HFUMS) offers a manner of determining the invasion potential of human breast cancer cells by eliciting the elevation of transient cytoplasmic calcium ions (Ca $^{2+}$ ). The fluorescent index (FI), which is a...

Non-noble-metal electrocatalysts of transition metal phosphides have been considered as promising catalysts for hydrogen evolution reaction (HER); however, their bifunctional catalytic activities are limited by unsatisfactory performance in oxygen evolution reaction (OER). Here we report ultrathin amorphous CoFeP nanosheets derived from CoFe layere...

The developments of personalized medicine, ultrasound imaging, and contactless “microscopic handle” techniques are pushing ultrasonic transducers toward features of high frequency, device miniaturization, and even novel function. However, the conventional ultrasonic transducer has severely limited the development of novel ideas for applications due...

Rational design and construction of high-quality multicomponent spinel ferrite with specific microstructures and solar light harvesting capabilities are highly desirable towards photocatalytic applications. In this study, novel zinc-magnesium-iron multinary spinel core-shell microspheres have firstly been prepared by an one-step solvothermal method...

At present, the lithium-rich metal oxide Li1+zMO2 (M = Ni, Co, Mn, etc.) is one of the promising cathodes materials for high-energy lithium-ion batteries. In this work, we report the effect of different doping amounts of fluoride ions on the microstructural and electrochemical properties of Li[Li0.2Mn0.54Ni0.13Co0.13]O2 cathode material. At low dop...

As the featured material of the superionic thermoelectric (TE) material family, copper-chalcogenide Cu2-xSe is attracting growing research interest for its excellent TE performance derived from the satisfactory power factor and the ultra-low thermal conductivity induced by the superionic effect. Various efforts have been made and proved to be effec...

In order to explore efficient photocatalysts for N 2 reduction reaction (NRR), 0D AgInS 2 nanoparticles and 2D MXene (Ti 3 C 2 ) nanosheets with different mass ratios are employed for building Z-scheme heterostructures. The resultant hybrids exhibit excellent interfacial charge transfer ability according to their optical and photo-electro propertie...