金在黄铁矿中的价态研究现状及存在问题OA

The chemical valence state of gold in pyrite hold significant theoretical and practical importance for understanding the mineralization mechanism of gold and optimizing selection and smelting processes.This article systematically reviews the progress of research into valence state types,occurrence states,incorporation mechanisms,and analytical methods of gold in pyrite.Gold in pyrite can exist in four valence states:Au+,Au3+,Au-,and Au0.Among these,Au0 and Au+have been clearly verified using techniques such as X-ray photoelectron spectroscopy(XPS),X-ray absorption near edge structure(XANES),and Mӧssbauer spectroscopy.They exist in the form of micro-and nano-scale particle gold and lattice gold in pyrite,respectively.However,spectral evidence for Au3+and Au-remains scarce,and the proposed occurrence of these states is largely based on theoretical inference.Spectroscopic techniques(e.g.,XANES and XPS)and microbeam analysis technology each have advantages and are often combined with Au-As solubility curves for comprehensive determination.Mechanisms by which Au is incorporated into the pyrite are still debated and are generally categorized into three types:direct precipitation/adsorption or later exsolution,charge-balanced coupled substitution,and isomorphic substitution.Although challenges remain in this research field,breakthroughs and progress are expected to result from the application of advanced technologies such as high-energy high-resolution X-ray absorption spectroscopy and atomic probe tomography,as well as the deepening of interdisciplinary cooperation in spectroscopy,materials science,and other fields.Such advancements are anticipated for key scientific issues,such as the identification of different valence states and determining the occurrence mechanisms of gold in pyrite.