SYNTHESIS UNDER AMBIENT PRESSURE OF 80-K SUPERCONDUCTING YBA2CU4O8 POWDERS VIA COPRECIPITATION

Sub-micron homogeneous powders of YBa2Cu4O 8 having Tc∼80 K were synthesised from aqueous solutions containing Y, Ba, Cu salts, and oxalic acid as a precipitant via a chemical coprecipitation method using triethylamine as a base. An accelerated formation-within 24 h-of nearly single phase YBa2Cu4O 8 powders was achieved. The intragrain critical current density at 5 K and H=1 T was determined to be 3.9×107 A/cm2. This process may have considerable potential in the large-scale preparation of YBa2Cu4O8