NCU Institute of Polymers and Energy Chemistry Makes Significant Research Progress in the Field of Energy Conversion and Storage

     NCU News (School of Chemistry & Chemical Engineering) Recently, Professor Chen Yiwang and his team, from the Institute of Polymers and Energy Chemistry (IPEC), School of Chemistry and Chemical Engineering, Nanchang University (NCU), have made important research progress in the field of energy conversion and storage. In the field of energy conversion, they achieved efficient and stable perovskite photovoltaic devices by adjusting the crystallization behavior of lead-based/non-lead-based[1] perovskite light absorption layers. In the field of energy storage, they prepared efficient oxygen reduction electrocatalysts and zinc metal batteries by constructing and modulating hierarchical nanostructures and electrode interfaces.

     Perovskite solar cells (PSCs) are a promising candidate for commercialization due to their simple solution processing method, excellent semiconducting properties, and compatibility with flexible wearable devices. However, the stability of PSCs is still a key factor restricting commercialization, especially when compared to traditional photovoltaic technologies which have a 20-year lifespan. The highly active components in the precursor solution used to prepare PSCs are prone to side reactions, which can cause inefficiency and instability in PSCs. Additionally, due to the limitations of solution characterization methods, it is still unknown how the colloidal assembly behavior in the precursor solution affects subsequent crystal growth. To address these issues, Professor Chen Yiwang and his team used state-of-the-art in situ liquid time-of-flight secondary ion mass spectrometry as a molecular probe to investigate the differences in precursor species and analyze the chemical evolution of precursor solutions after contact with air. This allowed them to intuitively unveil the aging chemistry of perovskite precursor solutions. Furthermore, they visualized the underlying relations between colloidal assembly and quantum well evolution in low-dimensional perovskite precursor solutions by combining the variation of hydrogen bond strength with differences in ion cluster content. This enabled them to create printable low-dimensional perovskite photovoltaics. To further demonstrate the universality of hydrogen bonding interactions in the nucleation and crystallization process, Professor Chen Yiwang and his team revealed an anti-solvent mechanism dominated by salting-out crystallization and a general principle for selecting anti-solvents based on hydrogen bond strength in the lead-free perovskite system. They also developed a new type of multifunctional green anti-solvent represented by acetic acid. In addition, they introduced the concept of multifunctional capsules to form porous channels and promote reactions at the solid-liquid interface, effectively solving the problem of residual lead iodide in the two-step sequential deposition process. Furthermore, the team improved the light utilization through down-conversion effect, resulting in the preparation of efficient and stable PSCs. They systematically elaborated on the generation and fundamental mechanisms of ion migration in PSCs and innovatively put forward prospective strategies for inhibiting ion migration from the perspective of the entire device, providing new ideas for achieving highly efficient and stable PSCs.

     In order to overcome bottlenecks, including performance, safety, and cost, faced by current commercial lithium-ion batteries, it is particularly important to develop next-generation environmentally friendly energy storage technologies that can improve device power density, energy density, and safety while reducing manufacturing costs. Due to their high abundance and low toxicity, aqueous zinc-based electrochemical energy storage devices have great development prospects. To improve the power density and stability of aqueous zinc-air batteries, the team developed a highly efficient oxygen reduction electrocatalyst by growing iron phthalocyanine-based polymers (PFePc) in situ on graphene functionalized with N-phenyl-2, 6-dimethyl benzamide using microwave-assisted polymerization. The laminar PFePc nanosheets were prepared by liquid-phase in situ charge-stripping strategy and were longitudinally linked to graphene as the high-performance oxygen reduction electrocatalyst. This was applied to liquid and flexible quasi-solid-state zinc-air batteries. In addition, to address the issues of disreputable dendrite growth, grievous hydrogen evolution and corrosion faced by Zn metal (one of the promising anode materials for aqueous batteries), a polycation additive, polydiallyl dimethylammonium chloride (PDD) was introduced. The PDD can simultaneously regulate the electric fields of electrolyte and Zn/electrolyte interface to improve Zn2+ migration behaviors and guide dominant Zn (002) deposition, successfully constructing high reversible and stable zinc metal batteries.

     The team has been conducting research on key materials and technologies for energy conversion and storage devices for a long time. They have developed a set of fully automated printing processes for large-scale preparation, integration and application of flexible solid-state energy conversion and storage devices, such as solar cells, supercapacitors, and metal-air batteries. At the same time, they have also achieved continuous breakthroughs in patent technologies and process optimization, providing support for further industrialization of the two fields.

     The team’s latest research results have been published consecutively in top chemical and material journals such as Angewandte Chemie International Edition, Advanced Materials, and Energy & Environmental Science (Angew. Chem. Int. Ed., 2023, 62, e2022157; Angew. Chem. Int. (Angew. Chem. Int. Ed., 2023, 62, e2022157; Angew. Chem. Int. Ed.,2023, e202303177; Angew. Chem. Int. Ed., 2023, 62, e2023016; Angew. Chem. Int. Ed., 2023, e202302701; Adver. Mater., 2023, 2301852; Adver. Mater.,2023, 2302552; Energy Environ. Sci.,2023, 10.1039/D3EE00202K) The first and corresponding author of the papers is affiliated with Nanchang University.

     Link to the papers：

     https://onlinelibrary.wiley.com/doi/10.1002/anie.202215799

     https://onlinelibrary.wiley.com/doi/10.1002/anie.202303177

     https://pubs.rsc.org/en/content/articlelanding/2023/EE/D3EE00202K

     https://onlinelibrary.wiley.com/doi/10.1002/adma.202301852

     https://onlinelibrary.wiley.com/doi/10.1002/adma.202302552

     https://onlinelibrary.wiley.com/doi/10.1002/anie.202301642

     https://onlinelibrary.wiley.com/doi/10.1002/anie.202302701

                                                                                                                                                                                                                                                        Editor：Zeng Hui

                                                                                                                                                                                                                                  Responsible Editor：Tu Jinfeng