Tuning Porosity and Surface Area in Mesoporous Silicon for Application in Li-Ion Battery Electrodes

Journal Article · Tue May 09 00:00:00 EDT 2017 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/acsami.6b16447· OSTI ID:1388860

Cook, John B. ^[1]; Kim, Hyung-Seok ^[2]; Lin, Terri C. ^[1]; Robbennolt, Shauna ^[1]; Detsi, Eric ^[1]; Dunn, Bruce S. ^[3]; Tolbert, Sarah H.  ^[4]

---

1. Univ. of California, Los Angeles, CA (United States). Dept. of Chemistry and Biochemistry
2. Univ. of California, Los Angeles, CA (United States). Dept. of Materials Science and Engineering
3. Univ. of California, Los Angeles, CA (United States). Dept. of Materials Science and Engineering, and The California NanoSystems Inst.
4. Univ. of California, Los Angeles, CA (United States). Dept. of Chemistry and Biochemistry, Dept. of Materials Science and Engineering, and The California NanoSystems Inst.

This work aims to improve the poor cycle lifetime of silicon-based anodes for Li-ion batteries by tuning microstructural parameters such as pore size, pore volume, and specific surface area in chemically synthesized mesoporous silicon. In this paper, we have specifically produced two different mesoporous silicon samples from the magnesiothermic reduction of ordered mesoporous silica in either argon or forming gas. In situ X-ray diffraction studies indicate that samples made in Ar proceed through a Mg₂Si intermediate, and this results in samples with larger pores (diameter ≈ 90 nm), modest total porosity (34%), and modest specific surface area (50 m² g^–1). Reduction in forming gas, by contrast, results in direct conversion of silica to silicon, and this produces samples with smaller pores (diameter ≈ 40 nm), higher porosity (41%), and a larger specific surface area (70 m² g^–1). The material with smaller pores outperforms the one with larger pores, delivering a capacity of 1121 mAh g^–1 at 10 A g^–1 and retains 1292 mAh g^–1 at 5 A g^–1 after 500 cycles. For comparison, the sample with larger pores delivers a capacity of 731 mAh g^–1 at 10 A g^–1 and retains 845 mAh g^–1 at 5 A g^–1 after 500 cycles. The dependence of capacity retention and charge storage kinetics on the nanoscale architecture clearly suggests that these microstructural parameters significantly impact the performance of mesoporous alloy type anodes. Our work is therefore expected to contribute to the design and synthesis of optimal mesoporous architectures for advanced Li-ion battery anodes.

• Research Organization: Energy Frontier Research Centers (EFRC) (United States). Nanostructures for Electrical Energy Storage (NEES)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0001160; SC0014213
• OSTI ID: 1388860
• Journal Information: ACS Applied Materials and Interfaces, Vol. 9, Issue 22; Related Information: NEES partners with University of Maryland (lead); University of California, Irvine; University of Florida; Los Alamos National Laboratory; Sandia National Laboratories; Yale University; ISSN 1944-8244
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
42 ENGINEERING
bio-inspired
energy storage (including batteries and capacitors)
defects
charge transport
synthesis (novel materials)
synthesis (self-assembly)
synthesis (scalable processing)
silicon
high power density
high energy density
mesoporous
magnesiothermic reduction
anode
Li ion battery