Is it possible for a some chemical reaction (keeping same initial material) behave like an endothermic or exothermic reaction by increasing the concentration of dopant (same doping material in the initial one, just change in concentration?
Please also recommend some publications.
If the dopant is crucial fro the 'displacement' of the chemical reaction towards exothermic or endothermic moments, yes it is very possible
it strongly depends on the dopant. But in general yes it is possible
It sounds like you're asking about heterogeneous catalysis, by which a material surface accelerates a chemical reaction by lowering the activation energy barriers between reactants and products. The energies of the reactants and products (that is, the initial and final states of the reaction) should be the same no matter what catalyst is used; however, even an exothermic reaction can proceed very slowly if there is a large "endothermic" activation energy barrier. A catalyst can help such a reaction proceed quickly at lower temperatures or smaller applied electrochemical bias.
The composition of a catalyst can be tuned to modify this activation energy barrier, e.g. by increasing the adsorption energy of a reactant (to spatially localize reactants together over active sites on the catalyst surface) or decreasing the adsorption energy of a product (to free up active sites for fresh reactions). This is called the Sabatier principle.
I suggest looking at work from the groups of Jens Norskov and Yang Shao-Horn. Norskov and co-workers laid the groundwork for relating the reactivity of pure metal and metal alloy catalysts to their electronic structure, and Shao-Horn's group adapted this work to oxides with complex compositions. Two important papers from these groups are linked.
In some cases, the "dopants" can be composed of the same element but with a different oxidation state. For example, Ti3+ or Ce3+ sites at TiO2 or CeO2 surfaces are particularly reactive electron donors. These dopants can form near oxygen vacancies and affect the chemistry of oxygen at or near the surface, as shown in the linked ACS paper.
http://www.nature.com/nchem/journal/v1/n7/full/nchem.367.html
http://www.sciencemag.org/content/334/6061/1383.abstract
http://pubs.acs.org/doi/abs/10.1021/ja200884w
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