Structural and electrochemical studies of α-manganese dioxide (α-MnO2)

Green synthesis of nanosized manganese dioxide as positive electrode for lithium-ion batteries using lemon juice and citrus peel

“…the so-called loss of lithium inventory (LLI). This type of structural evolution is currently observed for the hollandite α-MnO 2 electrode [36,58].…”

“…This stabilization is obviously observed for the subsequent cycles (Fig. 6), for which the set of intense redox peaks is located around 3.15 and 2.65 V, and the differential peak potential between E ox and E red is 0.5 V. This value is higher than the one reported for micro-sized materials [60] and did not vary significantly in the subsequent cycles. Tompsett et al [61] suggested that lithium ions are preferentially located at the off-center 8h sites, near the walls of the In case of the P-MnO 2 sample, the reduction process is characterized by an additional reduction peak located at 2.8 V. These features are attributed to the effect of the insertion-deinsertion mechanism in MnO 2 nanocrystallites with sizes smaller than 10 nm.…”

Mesoporous Hydrous Manganese Dioxide Nanowall Arrays with Large Lithium Ion Energy Storage Capacities

“…[3,4] However, the application of manganese dioxide in secondary lithium ion batteries has been hindered by some practical problems, such as its relatively low intercalation capacity and poor cycle stability; bulk manganese dioxide film could only deliver a capacity of less than 120 mA hg À1 and the host structure was easily distorted by the lithium-ion insertion/extraction reactions, thus suffering poor stability over long-term cycles. [5,6] Nanostructuring is considered to be an effective way to enhance the intercalation capacity and improve the cyclic stability. By providing a large electrode-electrolyte contact area and a shorter diffusion path for both lithium ion and electron transportation, [7][8][9][10] nanostructuring has been reported to enhance the lithium ion storage capacity of MnO 2 to exciting values of more than 200 mA hg À1 , [11][12][13] comparable to other high-capacity transitional metal oxides, such as nanostructured vanadium oxides.…”

The Structural Design of Electrode Materials for High Energy Lithium Batteries

“…For example, in the family of solid electrolytes, it is well known that structures with anomalously high Ag+-ion conductivity at room temperature can be fabricated by reacting AgI with other iodide salts such as RbI and C 11 H 30 N 3 I 3 to yield, respectively, RbAg 4 I 5 (RbI·4AgI) (Hull et al, 2002) and Ag 44 I 53 (C 11 H 30 N 3 I 3 ) 3 (44AgI·3C 11 H 30 N 3 I 3 ) (Thackeray et al, 1978). It is also now commonly known that Li 2 O units can stabilize a wide range of MnO 2 electrode structures such as gamma-MnO 2 and α-MnO 2 , resulting in Li 2 O·yMnO 2 products with superior electrochemical properties compared to the parent MnO 2 materials (Thackeray et al, 1993Johnson et al, 1997).…”