You will be shown an abstract from a materials science research paper. Your task is to extract all synthesis operations described in the abstract into a structured JSON format. Your output should be a JSON array. Each entry in the array should be a JSON object describing a single synthesis operation. This object should have the following fields:

- "trigger": A verbal predicate indicating a synthesis operation. This should be a string extracted directly from the abstract.
- "arguments": An array of arguments specifying aspects of the synthesis operation. Each entry in the array should be a length-2 array formatted as [<argument_text>, <argument_type>]. The `argument_text` should be a string extracted directly from the abstract. The `argument_type` should be one of the following types: ["Recipe_Precursor", "Atmospheric_Material", "Participant_Material", "Recipe_Target", "Solvent_Material"].

For instance, suppose an excerpt from the abstract reads:

Tetraethoxysilane (TEOS, 98%) and cetyltrimethylammonium bromide (CTAB, 98%) were purchased from Fluka. The MTTZ-siloxy derivative (triethoxysilyl-propyl-5-mercapto-1-methyl-tetrazole) was synthesized as previously described [38].

This excerpt includes two operations, which could be annotated as follows.

[{"arguments": [["Tetraethoxysilane", "Recipe_Precursor"], ["cetyltrimethylammonium bromide", "Recipe_Precursor"]], "trigger": "purchased"}, {"arguments": [["MTTZ-siloxy derivative", "Recipe_Target"]], "trigger": "synthesized"}]

In your response, please include the JSON and no other text.

Abstract:
10.1016/j.nanoen.2014.11.053
Power conversion of hybrid Bi2Te3/si thermoelectric nanocomposites

All chemicals were obtained from Sigma Aldrich and used without further purification. Fig. 1 is the schematic illustration of the fabrication process. (001) Si wafers were etched by mixed solution of 0.4 M AgNO3 and HF for 30 min. After the etching process, the by-products (Ag nanostructures) were removed by nitric acid, leaving the nanowire bundles (Fig. 1(a)). The samples were cleaned by deionized water and dilute HF is used to remove the surface oxide. Then different amount of hydrazine monohydrate (98%) was controlled and infiltrated through the as-formed nanowires (Fig. 1(b)). A solution of mixing BiCl3 (0.2 M) in nitric acid and H6TeO6 (0.15 M) in deionized water was prepared, followed by the addition of thioglycolic acid for the formation of the mixed complex at room temperature. Then the solution temperature was raised to 90 degC and Bi2Te3 nanoparticles were synthesized when dipping the hydrazine-coated samples in the as-prepared solution for the reduction of the Bi2Te3 (Fig. 1(c)). Different controlling parameters were conducted to elucidate the reaction process and obtain different morphologies (Fig. 1(d)). The as-synthesized samples were then washed with excess acetone and dried by N2 blow.
[{"arguments": [["AgNO3", "Participant_Material"], ["HF", "Participant_Material"], ["Si", "Recipe_Precursor"]], "trigger": "etched"}, {"arguments": [["by-products", "Participant_Material"], ["nitric acid", "Participant_Material"]], "trigger": "removed"}, {"arguments": [["samples", "Participant_Material"], ["HF", "Solvent_Material"], ["water", "Solvent_Material"]], "trigger": "cleaned"}, {"arguments": [["hydrazine monohydrate", "Participant_Material"]], "trigger": "controlled"}, {"arguments": [["nanowires", "Participant_Material"]], "trigger": "infiltrated"}, {"arguments": [["BiCl3", "Recipe_Precursor"], ["water", "Solvent_Material"], ["H6TeO6", "Recipe_Precursor"], ["nitric acid", "Solvent_Material"]], "trigger": "mixing"}, {"arguments": [["thioglycolic acid", "Participant_Material"]], "trigger": "addition"}, {"arguments": [["Bi2Te3", "Participant_Material"]], "trigger": "synthesized"}, {"arguments": [["hydrazine", "Participant_Material"]], "trigger": "dipping"}, {"arguments": [["samples", "Participant_Material"], ["acetone", "Solvent_Material"]], "trigger": "washed"}, {"arguments": [["N2", "Atmospheric_Material"]], "trigger": "dried"}]