Probing the origin of fluorescence quenching of a graphene-porphyrin hybrid materialDivya Sharma, Xiaoyan Zhang, Ben L. Feringa, Wesley R. Browne, Jennifer L. Herek and Annemarie HuijserEPJ Web of Conferences, 41 (2013) 04027DOI: https://doi.org/10.1051/epjconf/20134104027