scispace - formally typeset
Search or ask a question
Author

Caiyun Chang

Other affiliations: Chinese Academy of Sciences
Bio: Caiyun Chang is an academic researcher from Guangxi University. The author has contributed to research in topics: Materials science & Electrolyte. The author has an hindex of 5, co-authored 10 publications receiving 95 citations. Previous affiliations of Caiyun Chang include Chinese Academy of Sciences.

Papers
More filters
Journal ArticleDOI
TL;DR: In this article, a 3D nanoporous Zn anode for dendrite-free Zn plating/stripping with significantly suppressed undesirable side reactions was developed, and the continuously connected dual-channels for electron/ion transfers and improved effective solid-electrolyte interfaces also endow the anode with promoted fast kinetics.

195 citations

Journal ArticleDOI
TL;DR: In this paper, a textile-based direct current (DC) generator based on the tribovoltaic effect at a dynamic metal-semiconducting polymer interface was proposed.
Abstract: Generation of direct current (DC) from mechanical kinetic energies is crucial for realizing self-powered wearable electronics. Here, we report a flexible textile-based DC generator based on the tribovoltaic effect at a dynamic metal-semiconducting polymer interface. The tribovoltaic effect refers to a phenomenon in which an energy “quantum” is released once an atom−atom bond is formed at the dynamic interface of two contacting materials; such released “binding” energy excites electron−hole pairs at metal−semiconductor interfaces or semiconductor−semiconductor pn junctions. This textile DC generator, based on the dynamic Schottky junction between an Al slider and a poly(3,4-ethylenedioxythiophene)-coated textile, can output a voltage of approximately 0.45−0.70 V. The voltage and current can be increased by simply connecting multiple generators in series or in parallel. Seven generators in series can power an electronic watch constantly without any conditioning circuit. These findings offer an efficient strategy for harvesting mechanical energies and realizing selfpowered electronics. Kinetic energy harvesting is crucially important for the development of wearable electronics and the Internet of things. The energy of a battery is always limited, especially considering the pursuit of lightweight and miniature electronics, while renewable kinetic energy is free, ubiquitous, and sustainable. Therefore, developing a power-generating device to convert mechanical energies into electricity is essential to achieve self-powered electronics. The advent of triboelectric nanogenerators (TENGs) can solve part of this problem, which generate electric energy from various types of mechanical motions (human motion, vibration, rotation, wind, raindrop, ocean waves, etc.) based on the coupling effect of contact electrification and electrostatic induction. Conventional TENGs generally supply electricity in the form of alternating current with a high internal impedance; therefore, designing conditioning circuits for alternating-current (AC)− direct-current (DC) conversion and impedance matching is indispensable. In this case, the energy utilization efficiency is increased and the miniaturization and intelligent integration with functional sensors are difficult. Therefore, flexible DC generators with low internal impedance are in high demand. Several strategies have been reported to realize wearable devices that generate DC electricity from kinetic energy. First, DC electricity has been generated on the basis of the automatic switch of the two electrodes of a TENG with appropriate mechanical designs, but the intrinsic mechanism is still the same as that of an AC TENG. Another approach is based on the coupled effects of contact electrification and dielectric breakdown. The dielectric breakdown at the gap between one electrode and the electrified film results in a direct-current loop between the two electrodes. These two approaches share the common characteristic that charge transfers at the dynamic interfaces lead to the generation of electrostatic charges in the surface of dielectric materials. Recently, a third discovery was reported to generate DC current from dynamic metal− insulator−semiconductor (MIS) interfaces, dynamic P/ N-type semiconductor interfaces, or dynamic metal− semiconductor (MS) interfaces. Specifically, friction motions are designed at the dynamic PN junctions, Schottky MS interfaces, or MIS interfaces to excite non-equilibrium charge carries, which are separated by the built-in field to output DC current to the external circuits. The static metal− Received: February 8, 2021 Accepted: March 15, 2021 Leter http://pubs.acs.org/journal/aelccp © XXXX American Chemical Society 2442 https://doi.org/10.1021/acsenergylett.1c00288 ACS Energy Lett. 2021, 6, 2442−2450 D ow nl oa de d vi a G E O R G IA I N ST O F T E C H N O L O G Y o n Ju ne 1 5, 2 02 1 at 1 4: 41 :5 8 (U T C ). Se e ht tp s: //p ub s. ac s. or g/ sh ar in gg ui de lin es f or o pt io ns o n ho w to le gi tim at el y sh ar e pu bl is he d ar tic le s.

54 citations

Journal ArticleDOI
TL;DR: In this paper, a dual-mode textile triboelectric nanogenerator (TENG) is proposed to simultaneously scavenge multiple high-entropy kinetic energies, including human motions, raindrops, and winds.
Abstract: Distributed renewable kinetic energies are ubiquitous but with irregular amplitudes and frequencies, which, as one category of "high-entropy" energies, are crucial for next-generation self-powered electronics. Herein, we present a flexible waterproof dual-mode textile triboelectric nanogenerator (TENG), which can simultaneously scavenge multiple "high-entropy" kinetic energies, including human motions, raindrops, and winds. A freestanding-mode textile TENG (F-TENG) and a contact-separation-mode textile TENG (CS-TENG) are integrated together. The structure parameters of the textile TENG are optimized to improve the output performances. The raindrop can generate a voltage of up to ∼4.3 V and a current of about ∼6 μA, while human motion can generate a voltage of over 120 V and a peak power density of ∼500 mW m-2. The scavenged electrical energies can be stored in capacitors for powering small electronics. Therefore, we demonstrated a facile preparation of a TENG-based energy textile that is highly promising for kinetic energy harvesting and self-powered electronics.

33 citations

Journal ArticleDOI
TL;DR: In this paper, an antifreeze, long-life, and dendrite-free fiber-shaped Zn battery using both nanoporous Zn and polyaniline (PANI) electrodeposited on carbon nanofibers (CFs) as the cathode and anode, respectively.
Abstract: Fiber-shaped Zn batteries are promising candidates for wearable electronics owing to their high energy and low cost, but further studies are still required to address the issues related to detrimental Zn dendrite growth and limited low-temperature performances. Here, we report an antifreeze, long-life, and dendrite-free fiber-shaped Zn battery using both nanoporous Zn and polyaniline (PANI) electrodeposited on carbon nanofibers (CFs) as the cathode and anode, respectively. The fiber-shaped Zn anode achieves stable plating/stripping for 1000 mAh cm-2 accumulative capacity with low polarization (30 mV) at a current density of 2 mA cm-2. The dendrite-free Zn electrodes also enable the stable cycling of the fiber battery with 75.1% capacity retention after 1000 cycles. With an antifreeze agent added in the gel electrolyte, the fiber battery maintains excellent performance at temperatures as low as -30 °C. Lastly, by utilizing the doping/dedoping mechanism of Cl- in the PANI electrode, we achieve, for the first time, a Zn battery using human sweat as a harmless electrolyte. Our work provides a long-life and antifreeze fiber-shaped battery that is highly promising for future wearable energy storage devices.

28 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: In this article, the authors summarize the recent progress on general strategies to suppress zinc dendrites and zinc anode side reactions based on advanced materials and structure design, including the modification of the planar zinc electrode surface layer, internal structural optimization of the zinc bulk electrode, modification of electrolyte and construction of the multifunctional separator.
Abstract: Rechargeable aqueous metal-ion batteries are very promising as alternative energy storage devices during the post-lithium-ion era because of their green and safe inherent features. Among the different aqueous metal-ion batteries, aqueous zinc-ion batteries (ZIBs) have recently been studied extensively due to their unique and outstanding benefits that hold promise for large-scale power storage systems. However, zinc anode problems in ZIBs, such as zinc dendrites and side reactions, severely shorten the ZIB's cycle lifetime, thus restricting their practical application. Here, we sum up in detail the recent progress on general strategies to suppress zinc dendrites and zinc anode side reactions based on advanced materials and structure design, including the modification of the planar zinc electrode surface layer, internal structural optimization of the zinc bulk electrode, modification of the electrolyte and construction of the multifunctional separator. The various functional materials, structures and battery efficiencies are discussed. Finally, the challenges for ZIBs are identified in the production of functional zinc anodes.

419 citations

Journal ArticleDOI
TL;DR: In this paper, a novel anode with a surface-preferred (002) crystal plane is provided, which enables a long cyclic life of more than 500 h and a high average coulombic efficiency of 97.71% for symmetric batteries.
Abstract: Aqueous zinc-ion batteries are largely restricted by the unsatisfactory performance of zinc (Zn) anodes, including their poor stability and irreversibility. In particular, the mechanism behind the electrochemical contrast caused by the surface crystal plane, which is a decisive factor of the electrochemical characteristics of the hostless Zn anode, is still relatively indistinct. Hence, new insight into a novel anode with a surface-preferred (002) crystal plane is provided. The interfacial reaction and morphology evolution are revealed by theoretical analysis and post-mortem/operando experimental techniques, indicating that Zn anodes with more exposed (002) basal planes exhibit free dendrites, no by-products, and weak hydrogen evolution, in sharp contrast to the (100) plane. These features benefit the Zn (002) anode by enabling a long cyclic life of more than 500 h and a high average coulombic efficiency of 97.71% for symmetric batteries, along with delivering long cycling stability and reversibility with life spans of over 2000 cycles for full batteries. This work provides new insights into the design of high-performance Zn anodes for large-scale energy storage and can potentially be applied to other metal anodes suffering from instability and irreversibility.

283 citations

Journal ArticleDOI
TL;DR: In this article, the hydrogen evolution in Zn metal battery is accurately quantified by in situ battery-gas chromatography mass analysis, and the hydrogen fluxes reach 3.76 mmol h-1 cm-2 in a Zn/Zn symmetric cell in each segment, and 7.70 mmol h 1 cm -1 cm -2 in the Zn//MnO2 full cell.
Abstract: The hydrogen evolution in Zn metal battery is accurately quantified by in situ battery-gas chromatography-mass analysis. The hydrogen fluxes reach 3.76 mmol h-1 cm-2 in a Zn//Zn symmetric cell in each segment, and 7.70 mmol h-1 cm-2 in a Zn//MnO2 full cell. Then, a highly electronically insulating (0.11 mS cm-1 ) but highly Zn2+ ion conductive (80.2 mS cm-1 ) ZnF2 solid ion conductor with high Zn2+ transfer number (0.65) is constructed to isolate Zn metal from liquid electrolyte, which not only prohibits over 99.2% parasitic hydrogen evolution but also guides uniform Zn electrodeposition. Precisely quantitated, the Zn@ZnF2 //Zn@ZnF2 cell only produces 0.02 mmol h-1 cm-2 of hydrogen (0.53% of the Zn//Zn cell). Encouragingly, a high-areal-capacity Zn@ZnF2 //MnO2 (≈3.2 mAh cm-2 ) full cell only produces maximum hydrogen flux of 0.06 mmol h-1 cm-2 (0.78% of the Zn//Zn cell) at the fully charging state. Meanwhile, Zn@ZnF2 //Zn@ZnF2 symmetric cell exhibits excellent stability under ultrahigh current density and areal capacity (10 mA cm-2 , 10 mAh cm-2 ) over 590 h (285 cycles), which far outperforms all reported Zn metal anodes in aqueous systems. In light of the superior Zn@ZnF2 anode, the high-areal-capacity aqueous Zn@ZnF2 //MnO2 batteries (≈3.2 mAh cm-2 ) shows remarkable cycling stability over 1000 cycles with 93.63% capacity retained at ≈100% Coulombic efficiency.

282 citations