The result of uri_unescape contains bytes, not characters: 
$ perl -Mutf8 -MURI::Escape -E'say utf8::is_utf8(uri_unescape shift) ?
+ "characters" : "bytes"' %E4%BA%8E%E6%96%AF%E5%B1%88%E8%BE%BE%E5%B0%9
+4
bytes

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Perhaps you need to decode these bytes to the internal character representation and then encode them on output as you need: 
$ perl -MEncode=decode -MData::Dumper -MURI::Escape -e 'print Dumper d
+ecode utf8 => uri_unescape shift' %E4%BA%8E%E6%96%AF%E5%B1%88%E8%BE%B
+E%E5%B0%94
$VAR1 = "\x{4e8e}\x{65af}\x{5c48}\x{8fbe}\x{5c14}";

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Once you have characters instead of bytes you can encode them as you want using :encoding IOLayer or encode function from Encode module.
Sorry if my advice was wrong.

In reply to Re: string conversion problem by aitap
in thread string conversion problem by stormbow

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