Co 3 O 4 spinel has been widely investigated as a promising catalyst for the oxidation of volatile organic compounds (VOCs). However, the roles of tetrahedrally coordinated Co 2+ sites (Co 2+ T d ) and octahedrally coordinated Co 3+ sites (Co 3+ O h ) still remain elusive, because their oxidation states are strongly influenced by the local geometric and electronic structures of the cobalt ion. In this work, we separately studied the geometrical-site-dependent catalytic activity of Co 2+ and Co 3+ in VOC oxidation on the basis of a metal ion substitution strategy, by substituting Co 2+ and Co 3+ with inactive or low-active Zn 2+ (d 0 ), Al 3+ (d 0 ), and Fe 3+ (d 5 ), respectively. Raman spectroscopy, X-ray absorption fine structure (XAFS), and in situ DRIFTS spectra were thoroughly applied to elucidate the active sites of a Co-based spinel catalyst. The results demonstrate that octahedrally coordinated Co 2+ sites (Co 2+ O h ) are more easily oxidized to Co 3+ species in comparison to Co 2+ T d , and Co 3+ are responsible for the oxidative breakage of the benzene rings to generate the carboxylate intermediate species. CoO with Co 2+ O h and ZnCo 2 O 4 with Co 3+ O h species have demonstrated good catalytic activity and high TOF Co values at low temperature. Benzene conversions for CoO and ZnCo 2 O 4 are greater than 50% at 196 and 212 °C, respectively. However, CoAl 2 O 4 with Co 2+ T d sites shows poor catalytic activity and a low TOF Co value. In addition, ZnCo 2 O 4 exhibits good durability at 500 °C and strong H 2 O resistance ability.

Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOG-LIFE is a new long-term 'common-garden' experiment to disentangle the effects of species' wood traits and siterelated environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation.

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