Xingkang Huang

Carboxylic acid functionalized cellulose nanocrystals have been obtained from biomass and evaluated as aqueous, environmentally sustainable alternatives to conventional polyvinylidene difluoride binders for cathodes of lithium-ion batteries.

Printing techniques promote the development of solid-state batteries by constructing high performance cathodes, dendrite-free anodes, and ideal solid-state electrolytes with versatile structures and configurations.

Ni-rich layered cathode materials are at the forefront to be deployed in high energy density Li-ion batteries for the automotive market. However, the intrinsic poor structural and interfacial stability during overcharging could trigger violent thermal failure, which severely limits their wide application. To protect the Ni-rich cathode from overcharging, we firstly report a redox-active cation, thioether-substituted diaminocyclopropenium, as an electrolyte additive to limit the cell voltage within the safe value during overcharging. The organic cation demonstrates a record-breaking electrochemical reversibility at ∼4.55 V versus Li⁺/Li and solubility (0.5 M) in carbonate-based electrolyte. The protection capability of the additive was explored in two cell chemistries: a LiNi_0.8Co_0.15Al_0.05O₂/graphite cell and a LiNi_0.8Co_0.15Al_0.05O₂/silicon–graphene cell with areal capacities of ∼2.2 mA h cm⁻² and ∼3 mA h cm⁻², respectively. With 0.2 M addition, the LiNi_0.8Co_0.15Al_0.05O₂/graphite cell survived 54 cycles at 0.2C with 100% overcharge. Moreover, the cell can carry an utmost 4.4 mA cm⁻² (2C) with 100% overcharge and a maximum capacity of 7540% SOC at 0.2C.

A thin hollow C (HC) was synthesized to host a high phosphorus (P) loading of 75 wt%, forming a P@HC yolk/shell structure, which delivered a reversible capacity of 841 mA h g⁻¹, with excellent rate capability and stable cycling performance. P vapor concentration was found to be critical to the formation of P@HC or the P nanorod (PNR)/C composite. At a very high concentration of P vapor, well-crystallized PNRs were formed, which, however helped to identify the potassiation mechanism.

Bismuth has a great potential as an anode for PIBs, due to its layered structure with a large interlayer spacing, long mean free path, high volumetric capacity (3800 mA h L⁻¹) and environmental friendliness. Bismuthene, a 2D-layered structure, can be exfoliated from bismuth by mechanical or chemical methods. The unique structure of bismuthene is beneficial to the diffusion of potassium, penetration of the electrolyte, and buffering of the volume change along the c-axis, which will boost the anode performance of PIBs. An ultrasonication-assisted electrochemical exfoliation method was proposed in this study to prepare ultra-thin few layered bismuthene nanosheets (FBNs) simply and quickly. The as-prepared FBNs were employed in KIBs as an anode and delivered highly stable capacities of 423, 356, 275 and 227 mA h g⁻¹ at the current densities of 2.5, 5, 10, and 15 A g⁻¹, respectively. There was no obvious decay over 2500 cycles with a capacity of over 200 mA h g⁻¹ at 20 A g⁻¹, realizing excellent rate-capability and long-term cycling stability in KIBs. Furthermore, the mechanism of the excellent electrochemical performances was elucidated via in-depth characterization and theoretical calculations. This work provides a new strategy to prepare scalable ultra-thin nanosheets, which act as a promising candidate for the anode in energy storage systems.

Removing trace toxic heavy metals such as Pb²⁺ completely from drinking water while retaining beneficial ions such as Ca²⁺ and Mg²⁺ is important for protecting human health. A novel concept of zero-wastewater CDI is demonstrated to selectively remove lead ions against Ca²⁺ and Mg²⁺.

Recent outbreaks of the Ebola virus infection in several countries demand a rapid point-of-care (POC) detection strategy. This paper reports on an innovative pathway founded on electronic resonance frequency modulation to detect Ebola glyco-protein (GP), based on carrier injection-trapping-release-transfer mechanism and standard antibody-antigen interaction principle within a dielectric-gated (Al2O3) reduced graphene oxide (rGO) field-effect transistor (GFET). The sensitivity of the current Ebola detection can be significantly enhanced by monitoring the device’s electronic resonance frequency, such as inflection frequency (fi), where phase angle reaches maximum (θmax). In addition to excellent selectivity, a sensitivity of ~36-160 % and ~17-40 % for 0.001-3.401 mg/L Ebola GP can be achieved at high and low inflection resonance frequencies, respectively, which are several orders of magnitude higher than the sensitivity from other electronic parameters (e.g., re-sistance-based sensitivity). Using equivalent circuit modelling on contributions of channel and contact, analytical equations for resonance shift have been generalized. When matching with the incoming ac measurement signal, electronic resonance from the phase angle spectrum is evolved from various relaxation processes (e.g., trap and release of injected charge at sur-face trap sites of channel-gate oxide and channel-source/drain interface) that are associated with a characteristic emission frequency. Using charge relaxation dynamics, a high-performance bio-FET sensing platform for healthcare and bio-electronic applications is realized through resonance shifting.

Benefiting from the reversible conversion reaction upon delithiation, nano-sized SnO2, with its theoretical capacity of 1,494 mAh g-1, has gained special attention as a promising anode material. Here we report a self-assembled SnO2/Sn-reduced graphene oxide (rGO) sandwich nanocomposite developed by organometallic precursor coating and in-situ transformation. Ultra-fine SnO2 nanoparticles with an average diameter of 5 nm are sandwiched within the rGO/carbonaceous network, which not only greatly alleviates the volume changes upon lithiation and aggregation of SnO2 nanoparticles, but also facilitates the charge transfer and reaction kinetics of SnO2 upon lithiation/de-lithiation. As a result, the SnO2/Sn-rGO nanocomposite exhibited a superior lithium storage capacity with a reversible capacity of 1,307 mAh g-1 at a current density of 80 mA g-1 in the potential window of 0.01 – 2.5 V vs. Li+/Li, and showed a reversible capacity of 767 mAh g-1 over 200 cycles at a current density of 400 mA g-1. When cycling at a higher current density of 1,600 mA g-1, the SnO2/Sn-rGO nanocomposite showed a highly stable capacity of 449 mA g-1 without obvious decay after 400 cycles.