Tingjun Wu

Dr. Tingjun Wu


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 June 2018 in Materials
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Journal Article
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TWTingjun Wu
Tingjun Wu
Peng GaoPeng Gao
Peng Gao
Oxide perovskite materials have a long history of being investigated for thermoelectric applications. Compared to the state-of-the-art tin and lead chalcogenides, these perovskite compounds have advantages of low toxicity, eco-friendliness, and high elemental abundance. However, because of low electrical conductivity and high thermal conductivity, the total thermoelectric performance of oxide perovskites is relatively poor. Variety of methods were used to enhance the TE properties of oxide perovskite materials, such as doping, inducing oxygen vacancy, embedding crystal imperfection, and so on. Recently, hybrid perovskite materials started to draw attention for thermoelectric application. Due to the low thermal conductivity and high Seebeck coefficient feature of hybrid perovskites materials, they can be promising thermoelectric materials and hold the potential for the application of wearable energy generators and cooling devices. This mini-review will build a bridge between oxide perovskites and burgeoning hybrid halide perovskites in the research of thermoelectric properties with an aim to further enhance the relevant performance of perovskite-type materials.

21 December 2021 in Frontiers in Chemistry
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Journal Article
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TWTingjun Wu
Tingjun Wu
JKJiwon Kim
Jiwon Kim
JLJae-Hong Lim
Jae-Hong Lim
MKMin-Seok Kim
Min-Seok Kim
NMNosang V. Myung
Nosang V. Myung
Thermoelectric devices based power generation and cooling systemsystem have lot of advantages over conventional refrigerator and power generators, becausebecause of solid-state devicesdevices, compact size, good scalability, nono-emissions and low maintenance requirement with long operating lifetime. However, the applications of thermoelectric devices have been limited owingowing to their low energy conversion efficiency. It has drawn tremendous attention in the field of thermoelectric materials and devices in the 21st century because of the need of sustainable energy harvesting technology and the ability to develop higher performance thermoelectric materials through nanoscale science and defect engineering. Among various fabrication methods, electrodeposition is one of the most promising synthesis methods to fabricate devices because of its ability to control morphology, composition, crystallinity, and crystal structure of materials through controlling electrodeposition parameters. Additionally, it is an additive manufacturing technique with minimum waste materials that operates at near room temperature. Furthermore, its growth rate is significantly higher (i.e.,a few hundred microns per hour) than the vacuum processes, which allows device fabrication in cost effective matter. In this paper, the latest development of various electrodeposited thermoelectric materials (i.e.,Te, PbTe, Bi2Te3and their derivatives, BiSe, BiS, Sb2Te3) in different forms including thin films, nanowires, and nanocomposites were comprehensively reviewed. Additionally, their thermoelectric properties are correlated to the composition, morphology, and crystal structure.

21 February 2023 in Materials
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XYXi Yu
Xi Yu
LZLei Zhu
Lei Zhu
XLXin Li
Xin Li
JZJia Zhao
Jia Zhao
TWTingjun Wu
Tingjun Wu
WLWeimin Li
Weimin Li
The piezoelectric and elastic properties are critical for the performance of AlN-based 5G RF filters. The improvement of the piezoelectric response in AlN is often accompanied by lattice softening, which compromises the elastic modulus and sound velocities. Optimizing both the piezoelectric and elastic properties simultaneously is both challenging and practically desirable. In this work, 117 X0.125Y0.125Al0.75N compounds were studied with the high-throughput first-principles calculation. B0.125Er0.125Al0.75N, Mg0.125Ti0.125Al0.75N, and Be0.125Ce0.125Al0.75N were found to have both high C33 (>249.592 GPa) and high e33 (>1.869 C/m2). The COMSOL Multiphysics simulation showed that most of the quality factor (Qr) values and the effective coupling coefficient (Keff2) of the resonators made with these three materials were higher than those with Sc0.25AlN with the exception of the Keff2 of Be0.125Ce0.125AlN, which was lower due to the higher permittivity. This result demonstrates that double-element doping of AlN is an effective strategy to enhance the piezoelectric strain constant without softening the lattice. A large e33 can be achieved with doping elements having d-/f- electrons and large internal atomic coordinate changes of du/dε. The doping elements–nitrogen bond with a smaller electronegativity difference (ΔEd) leads to a larger elastic constant C33.

1 September 2025 in Frontiers in Chemistry
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TWTingjun Wu
Tingjun Wu
JKJiwon Kim
Jiwon Kim
YCYong-Ho Choa
Yong-Ho Choa
NMNosang V. Myung
Nosang V. Myung
FexCo1-x thin films were electrodeposited from a choline–urea deep eutectic solvent (DES) containing Fe3+ and Co2+ ions under ambient conditions. Anomalous co-deposition was observed, with Fe preferentially depositing over Co. With higher cathodic potential, the film’s morphology shifted from smooth to nodular. X-ray diffraction (XRD) analysis showed iron oxide impurities at lower overpotential and temperatures (e.g., <−0.9 V at 70 °C), while impurity-free, nanocrystalline Co50Fe50 films had formed at higher temperatures (e.g., 130 °C). The films exhibited a body-centered cubic (BCC) structure with (110) preferred orientation and grain sizes of 30 nm–40 nm.

21 March 2021 in Coatings
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TWTingjun Wu
Tingjun Wu
JLJae-Hong Lim
Jae-Hong Lim
Kyu Hwan LeeKyu Hwan Lee
Kyu Hwan Lee
JKJiwon Kim
Jiwon Kim
NMNosang V. Myung
Nosang V. Myung
The Te-embedded PbTe nanocrystallline thick films (i.e., 50 µm) were electrodeposited, where the fraction and average grain size of PbTe and Te phases were tuned by adjusting the applied potential followed by post thermal treatment. The crystal grain boundary and Te nano-inclusion in the films played critical roles in their thermoelectric properties. The Te-embedded PbTe thick film with the average grain size of around 100 nm showed lower energy barrier height (EB = 0.023 eV) than thick films with the average grain size of a few tens of nm (EB = 0.11). Although decrease in the energy barrier reduced the Seebeck coefficient, however, it enhanced the electrical conductivity, which resulted in an increase in power factor (PF). The highest power factor was 183 μw K−2 cm−1, achieved at the energy barrier of 0.023 eV.

30 April 2025 in Electrochem
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YDYu Duan
Yu Duan
YLYedi Li
Yedi Li
TWTingjun Wu
Tingjun Wu
WXWei Xu
Wei Xu
LZLei Zhu
Lei Zhu
WYWenjie Yu
Wenjie Yu
Cobalt electrochemical deposition, with its bottom–up growth properties, is a core technology for creating metal interconnects. Additives are crucial during electrodeposition to control the quality of deposits by adsorbing onto the Co surface. The functional groups of additive molecules are the key to tailoring the adsorption behavior. This study focuses on heteroaromatic thiol additives, including 2-mercaptobenzimidazole (MBI), 2-mercapto-5-benzimidazolesulfonic acid sodium salt dehydrate (MBIS), and 2-mercaptobenzoxazole (MBO). Cyclic voltammetry, chronopotentiometry, quantum chemical calculations, and characterization tests were employed to investigate the adsorption behavior of additive molecules with different functional groups on cobalt. The results indicate that the inhibitory strength of the three additives on electrodeposition follows the following order: MBI > MBIS > MBO. The strong inhibitory effect of MBI primarily stems from the adsorption of the thiol group, the pyridine-like nitrogen in the heterocycle, and the benzene ring. MBIS exhibits reduced inhibitory capability due to the combined effects of the sulfonic acid group and hydrolysis ionization. MBO, with the introduction of an oxygen atom in the heterocycle, shows the weakest adsorption and inhibitory capability among the three.